European Journal of Taxonomy 168: 1-32

http://dx.doi.org/10.5852/ejt.2015.168

This work is licensed under a Creative Commons Attribution 3.0 License.

ISSN 2118-9773

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2015 • Sidorov D.A. et al.

Research article

urn:lsid:zoobank.org:pub:BD52040D-6774-4181-AB53-4629CCA310F9

A new genus and two new species of cavernicolous amphipods

(Crustacea: Typhlogammaridae) from the Western Caucasus

Dmitry A. SIDOROV ■*, Andrey A. GONTCHAROV 2 & Svetlana N. SHARINA 3

12 Institute of Biology and Soil Science, Far Eastern Branch of the Russian Academy of Sciences,

100-let Vladivostoku Av. 159, Vladivostok 690022, Russia.

3 A.V. Zhirmunsky Institute of Marine Biology, Far Eastern Branch of the Russian Academy

of Sciences, 17 Palchevskogo St., Vladivostok 690041, Russia.

3 Far Eastern Federal University, 8 Suhanova St., Vladivostok 690950, Russia.

* Corresponding author: [email protected]

1 urn:lsid:zoobank.org: author: CA39E974-5B23-42CE-919D-5EC937301494

2 um:lsid:zoobank.org:author:D16C97A5-FB70-414A-ACCE-D17519AlBE6C

3 um:lsid:zoobank.org:author:3159D4D5-2BFl-4E12-8280-2BD3F83C8F55

Abstract. This study deals with the biodiversity and distribution of cavernicolous Amphipoda in caves

of the Arabika massif (Western Caucasus). The Sarma, Trojka and Orlinoe Gnezdo caves were explored

during speleological expeditions over the years 2011-12. Two new species of Amphipoda were found:

a sub-surface dweller Zenkevitchia sandroruffoi sp. nov. is reported from the Sarma, Trojka and Orlinoe

Gnezdo caves at depths from -30 m to -350 m; the second one, a deep dweller Adaugammaruspilosus

gen. et sp. nov. is reported from the Sarma Cave at depths of -1270 to -1700 m. Adaugammarus gen.

nov. shares similarities with Typhlogammarus Schafema, 1907 and Zenkevitchia Birstein, 1940. The

species Anopogammarus birsteini Derzhavin, 1945 is also re-described herein based on new samples

that suggest close affinity of this species with the family Gammaridae. The original taxonomic

combination is resurrected for Zenkevitchia revazi Birstein & Fjovuschkin, 1970, comb, resurr. (from

Anopogammarus Derzhavin, 1945). To accommodate morphologically different species in the genus

Zenkevitchia , two new groups are proposed. These are the admirabilis- group (Z. admirabilis Birstein,

1940 and Z yakovi Sidorov, 2015) and the sandroruffo z - group (Z. sandroruffoi sp. nov. and Z. revazi).

An updated molecular ( mt-coxl ) phylogeny, an identification key to the genera and a distribution map

for the typhlogammarid amphipod species of Transcaucasia are provided.

Keywords. Gammaroidea, mtDNA, phylogeny, Sarma Cave, subterranean species.

Sidorov D.A., Gontcharov A.A. & Sharina S.N. 2015. A new genus and two new species of cavernicolous

amphipods (Crustacea: Typhlogammaridae) from the Western Caucasus. European Journal of Taxonomy 168:

1-32. http://dx.doi.org/10.5852/ejt.2015.168

European Journal of Taxonomy 168 : 1-32 ( 2015 )

Introduction

The Arabika karst massif is one of the largest and highest in the limestone band of the Western Caucasus.

It is bounded by the canyons of the rivers Kutu-Sara, Gega and Bzyb on the North and East, by the Black

Sea coast on the Southwest and by the valleys of the Khashupse and Tsandrypsh rivers in the West. The

following separation and nomenclature for the speleological areas of the Arabika massif is adopted:

the Ortobalagan trough, GeTgeluk trough, TreugoTnik caving district (Zont-Utug-Khyrka), Minskaja

Valley trough and the Dzou tract.

Since Birstein and co-authors (Birstein 1940; Birstein & Topaschov 1940) presented their first studies

on the biodiversity of subterranean animals in Transcaucasia, both significant speleological discoveries

were made and taxonomic views changed considerably. Dozens of new caves have been explored

(Dublyansky et al. 1987) and several new taxa have been discovered (Birstein & Tjovuschkin 1967).

The contemporary period is marked by several publications on the cavernicolous fauna of the region

(Marin & Sokolova 2014; Vinarski et al. 2014; Sidorov et al. 2015), including biospeleological studies

on caves located in the Arabika massif (Jordana et al. 2012; Sendra & Reboleira 2012; Sidorov et al.

2014). However, the invertebrate troglofauna of the Western Caucasus and surrounding areas is still

poorly known (Barjadze et al. 2015).

The family Typhlogammaridae was proposed by Bousfield (1978) and consists of five genera:

Typhlogammarus Schaferna, 1907; Metohia Absolon, 1927; Zenkevitchia Birstein, 1940; Anopo-

gammarus Derzhavin, 1945 and Accubogammarus G. Karaman, 1974 (Schaferna 1907; Absolon 1927;

Fig. 1. Distribution map of Typhlogammaridae species and Anopogammarus in the Transcaucasia.

1. Zenkevitchia sandroruffoi sp. nov. 2. Adaugammarus pilosus gen. et sp. nov. 3. Zenkevitchia sp.

sensu Jaume in Sendra & Reboleira (2012). 4. Zenkevitchia admirabilis (complex of species).

5. Zenkevitchia yakovi Sidorov, 2015. 6. Zenkevitchia revazi Birstein & Tjovuschkin, 1970, comb,

resurr. 7. Anopogammarus birsteini Derzhavin, 1945.

SIDOROV D.A. et al ., New genus and species of Typhlogammaridae

Birstein 1940; Derzhavin 1945; Karaman 1974). The typhlogammarids mostly inhabit subterranean

waters in caves and are sometimes observed in the karstic springs of the Balkan-Transcaucasian region.

An interesting feature of this group of invertebrates is their ability to move across the stone surface

within a thin film of water, the so-called “cave hygropetric habitat” (Sket 2004).

In this paper, we present results of a biospeleological survey from the most studied caving area,

Treugol’nik, with about 30 known caves including one of the world’s deepest caves, the Sarma Cave.

The Sarma, Trojka and Orlinoe Gnezdo caves were studied and among other things (Sidorov et al.

2014), amphipods of the Typhlogammaridae family were collected there. The DNA barcode region of

the mitochondrial cytochrome c oxidase subunit 1 (COI) gene sequence was used to verity the distinction

of described species, along with comparative morphological analyses.

Material and methods

Specimen collection

The samples of blind, unpigmented aquatic amphipods were collected in three limestone caves; the

meters refer to the explored cave depth: Sarma (-1830 m), Trojka (-257 m), and Orlinoe Gnezdo (-75 m)

in the Arabika massif of Abkhazia (Fig. 1, Table 1). Additionally, samples containing specimens of

Anopogammarus birsteini Derzhavin, 1945 were collected at the type locality near Goluboe Take

in the Gagra District of Abkhazia. Specimens were preserved in 96% ethanol at each field site. The

geographical map showing the sampling sites and distribution pattern of the Typhlogammaridae species

in the Western Caucasus was constructed with GMT 4.5.6.-1. GIS software (Fig. 1).

Morphology and taxonomic terms

The body length of the amphipods was recorded by holding the specimen straight and measuring the

distance along the dorsal side of the body from the base of the first antenna to the base of the telson, using

a micrometer eye piece in a Tomo MBS-9 dissecting microscope. Appendages were drawn with a Carl

Zeiss NU-2 compound microscope equipped with a drawing device as described in Gorodkov (1961).

Heavily calcified specimens of crustaceans were placed in 4% lactic acid and then washed and boiled

in clean water to remove air bubbles within the segments. Permanent preparations were made using a

methylene blue staining solution, and polyvinyl lactophenol (PVL) was used as the mounting medium.

The descriptive terminology follows the classification system in the original conventional sense and

does not agree with the homology concepts proposed by Watling (1989). To make the nomenclature

more stable, we use the term “spine” for robust setae and the term “seta” for slender, usually flexible

structures. The term “palmar angle” of the gnathopod propodi refers to the angle formed at the end of

the palm and beginning of the posterior margin or at the point where the tip of the dactylus closes on the

propodus (Birstein 1941). The fore-gut lateralia comprise a potentially useful morphological character

in the phylogenetic analysis (Coleman 1991). The nomenclature for setal patterns on article 3 of the

mandibular palp follows the practice of Karaman (1970) and Stock (1974). The descriptions are based

on the type series and all material examined is deposited in the Zoological Museum of the Far East

Federal University, Vladivostok (FEFU; the holotypes are kept there) or in the research collection of

D.A. Sidorov at the Institute of Biology and Soil Science, Vladivostok (IBSS).

DNA extraction, amplification, sequencing and analysis

Total DNA was extracted from the muscle tissue with a DNeasy Blood & Tissue kit (QIAGEN GmbH,

Hilden, Germany) according to the manufacturer’s protocol. The COI gene fragment was amplified

using the universal primers HC02198 and LCO1490 (Folmer et al. 1994). The annealing temperature

was set at 40°C for 20 s. The PCR products were sequenced directly using the same primers and a

BigDye terminator v. 3.1 sequencing kit (Applied Biosystems, USA). Sequences were analyzed on an

ABI 3130 genetic analyzer (Applied Biosystems, USA) and assembled with the Staden Package v. 1.4

European Journal of Taxonomy 168: 1-32 (2015)

Table 1 . List of the specimens, sampling sites and accession numbers of the sequences included in this

study. References are given for sequences obtained from GenBank.

GenBank

Reference/

Specimen

Locality

acc. no.

or year of

COI

sampling

Adaugammarus pilosus

SC1270ml

Georgia, Abkhazia: Sarma Cave, -1270 m

KT427516

This study (2011)

Adaugammarus pilosus

SC1270m2

Georgia, Abkhazia: Sarma Cave, -1270 m

KT427517

This study (2011)

Adaugammarus pilosus

SC1270m3

Georgia, Abkhazia: Sarma Cave, -1270 m

KT427518

This study (2011)

Adaugammarus pilosus SC 1700m

Georgia, Abkhazia: Sarma Cave, -1700 m

KT427519

This study (2011)

Zenkevitchia sandroruffoi

SC230m

Georgia, Abkhazia: Sarma Cave, -230 m

KT427520

This study (2012)

Zenkevitchia sandroruffoi

SC350m

Georgia, Abkhazia: Sarma Cave, -350 m

KT427521

This study (2012)

Zenkevitchia sandroruffoi TC

Georgia, Abkhazia: Trojka Cave, -30 m

KT427522

This study (2012)

Zenkevitchia sandroruffoi OG1

Georgia, Abkhazia: Orlinoe Gnezdo Cave, -75 m

KT427523

This study (2011)

Zenkevitchia sandroruffoi OG2

Georgia, Abkhazia: Orlinoe Gnezdo Cave, -75 m

KT427524

This study (2011)

Zenkevitchia sandroruffoi OG3

Georgia, Abkhazia: Orlinoe Gnezdo Cave, -75 m

KT427525

This study (2011)

From GenBank

Accubogammarus sp.

SLOCHN114

Montenegro: Grahovo, Vojvode Dakovica cave

KF478592

Hou etal. 2014

Anopogammarus revazi

SLOCHN245

Georgia: Martvili, Motena cave

KF478522

Hou et al. 2014

Metohia carinata SLOCHN019

Montenegro: Rijeka Cmojevica, Obodska cave

KF478584

Hou etal. 2014

Metohia carinata SLOCHN025

Bosnia-Herzegovina: Cicevo, Velja gora, Sumet

cave

KF478585

Hou et al. 2014

Typhlogammarus mrazeki

SLOCHN020

Bosnia-Herzegovina: Popovo polje, Zavala,

Vjetrenica cave

KF478586

Hou et al. 2014

Typhlogammarus mrazeki

SLOCHN113

Montenegro: Cetinje, Lipska cave

KF478590

Hou etal. 2014

Typhlogammarus sp.

SLOCHN252

Croatia: Zrmanja, Krupa cave

KF478591

Hou et al. 2014

Zenkevitchia admirabilis

SLOCHN199

Georgia, Abkhazia: Suhumi, Verhnie Peseri,

Verhne-esherskaja (=Sobachya) cave, approx.

43°0658N, 40°9922 E

KF478600

Hou et al. 2014

Zenkevitchia admirabilis

SLOCHN200

Georgia, Abkhazia: Gudauta, Lihni, Tarkili

(=Tarkiladze) cave, 43.19441 N, 40.65165 E

KF478599

Hou etal. 2014

Zenkevitchia yakovi T

Georgia, Abkhazia: “lstocnik TcebeTda” cave,

43°0262 N 41°2830 E

KP844572

Sidorov et al. 2015

Zenkevitchiayakovi SI

Georgia, Abkhazia: Sredne-Shakuranskaya cave,

43°0297 N 41°3331 E

KP844573

Sidorov et al. 2015

Zenkevitchia yakovi S2

Georgia, Abkhazia: Sredne-Shakuranskaya cave,

43°0297 N 41°3331 E

KP844574

Sidorov et al. 2015

SIDOROV D.A. et al., New genus and species of Typhlogammaridae

(Bonfield et al. 1995). The Akaike information criterion (AIC2) in Mo del Generator 0.85 (Keane et al.

2006) was used to select the model of sequence evolution best fitting our data set (HKY+G+I). The data

set was analyzed using the maximum-likelihood (ML) algorithm in Mega 6.0 (Tamura et al. 2013), and

pairwise sequence divergence was estimated using the same environment. A standard BioNJ initial tree

was obtained automatically by applying the Nearest-Neighbor-Interchange (NNI) for tree inference. To

assess support for clades 1,000 bootstrap replicates (Felsenstein 1985) were performed.

Entrance 2150 orthometric height

Stary Meander

i l

500

2 \

-> 5 Q Zebra system

' ~~

ik 1

* u

Z. sandroruffoi, sp. nov.

"'VL

Zenkevitchia sandroruffoi

-750

1000

- 1250

P250 Champion

V \

** — . K ..

' V'-*£!> | \

" > V Staroe Dno system

Dolgy meander

1 \

V Jr %

. \

I -!

1 \ A

Pokemons' system a#'*'"

Reliktovaya system '**-

Novy Povorot system

*§

;• is; \ )

Propaschee Dno

- 1500

Ponkratenko gallery _ 1460 ;

- 1540 '

-U V

-1500 "

> •

- 1750

-1% _

A 3 1

jt -1760

(

1830

Fig. 2. Vertical distribution of amphipod species in the Sarma Cave. Map adapted from Sidorov et al.

(2014), compiled by V.V. Sukhachev.

European Journal of Taxonomy 168 : 1-32 ( 2015 )

Results

Order Amphipoda Latreille, 1818

Family Gammaridae Leach, 1814

Genus Anopogammarus Derzhavin, 1945

Anopogammarus birsteini Derzhavin, 1945

Figs 4A-E, 5-6

Anopogammarus birsteini Derzhavin, 1945: 34, pi. 2.

Anopogammarus birsteini- Birstein & Ljovuschkin 1967: 1512; 1970: 1478, figs 4-6. — Stock 1973:

339. — Bousfield 1977: 291. — Karaman & Barnard 1979: 142. — Barnard & Karaman 1980: 8. —

Barnard & Barnard 1983: 502. —Ruffo 1995: 450. —Karaman & Ruffo 1995: 159, 160.

Material examined

GEORGIA: 1 §, 1 <$, Western Caucasus, Gagra District, near Goluboe Lake (43°3508 N, 40°4119 E).

Specimens, completely dissected and mounted on a single slide per number: $ (oostegites initial, non-

setose) 9.0 mm, $ 8.5 mm, 15 Jun. 2015, 133 m a.s.l., springs, coll. D.M. Palatov (X44039/Cr-1645-

46-FEFU).

Additional material examined

GEORGIA: 5 $ $ (6.0 mm, 3x7.0 mm, 7.5 mm; oostegites initial, non-setose), 5 $$ (3x6.0 mm, 7.5 mm,

9.0 mm), 3 juv., specimens measured, partially dissected and stored in different vials (1-12/lsd-IBSS),

same data as above.

Zenkevitchia revazi

Fig. 3. Unrooted ML-tree with bootstrap support values based on the mt-coxl sequences (values less

than 50% not shown). Specimen labels refer to information given in Table SI. Scale bar indicates the

number of substitutions per site.

SIDOROV D.A. et al.. New genus and species of Typhlogammaridae

A- t

0.4 mm

0.05 mm

Fig. 4. — A-D. Anopogammarus birsteini Derzhavin, 1945. 9.0 mm , X44039/Cr-1645-FEFU:

A. Habitus from left side. B. Urosome. C. Head. D. Metasomal and urosomal segments with telson. —

E-G. Zenkevitchia sandroruffoi sp. nov. Paratype, $, 6.3 mm, X44045/Cr-1651-FEFU. E. Lateralia.

F. Head. G. Urosome. — H-K. Adaugammarus pilosus sp. nov. Holotype, $, 13.5 mm, X44046/Cr-

1652-FEFU. H. Lateralia. I. Head. J. Urosome. K. Lateralia.

European Journal of Taxonomy 168 : 1-32 ( 2015 )

0.2 mm

Fig. 5. Anopogammarus birsteini Derzhavin, 1945. 9.0 mm, X44039/Cr-1645-FEFU. A. Ante nn a

1. B. Antenna 2. C-D. Palmar margins of gnathopods 1 and 2 propodi. E. Maxilla 1. F. Outer plate of

maxilla 1. G. Palp of right maxilla 1.

SIDOROV D.A. et al ., New genus and species of Typhlogammaridae

Remark

Although A. birsteini was described by Derzhavin (1945) based on an 8.0 mm female and was

subsequently redescribed in detail (Birstein & Ljovuschkin 1970) based on both sexes, we further

introduce an amended diagnostic description to emphasize some important characters.

Diagnostic description

Size. Female body length 9.0 mm and male, body length 8.5 mm (X44039/Cr-1645-46-FEFU). Robust,

large-sized species of gammarid-like habitus (sexual dimorphism weakly pronounced, i.e., females

larger than males). Coxal gills 2-7 stalked, triangular or sacciforme, largest on gnathopod 2, successively

smaller on pereopods 3 to 7, gill 7 the smallest. Body length 6.0-17.0 mm (§), 6.0-14.0 mm (3).

General body morphology (Figs 4A-D, 6G). Body smooth, lacking dorsal cuticular elements. Head

as long as first pereon segment; rostrum absent; inferior antennal sinus shallow, sub-rounded. Eyes

absent. Pleosomites and urosomites on dorsal surface with lateral groups of spines and setae; medial

elements absent. Dorsal surface of urosomites 1-3 armed with robust spines in the following manner:

1 (3-0-0-3), 2 (2-0-0-2), 3 (1-0-1). Epimeral plate 1: postero-ventral corner prominent; posterior and

ventral margins convex; 2 stiff setae along ventral margin, 2 setae along posterior margin. Epimeral

plate 2: postero-ventral corner acuminate; posterior and ventral margins convex; 5 stiff setae in two rows

along ventral margin, 1 seta along posterior margin at corner. Epimeral plate 3: postero-ventral corner

Fig. 6. Anopogammarus birsteini Derzhavin, 1945. $, 9.0 mm, X44039/Cr-1645-FEFU. A. Pleopod 2.

B. Coupling setae of pleopod 2. C. Uropod 1. D. Uropod 2. E-F. Uropod 3. G. Telson.

European Journal of Taxonomy 168 : 1-32 ( 2015 )

acuminate; posterior margin concave; ventral margin convex; 4 stiff seta along ventral margin, 2 setae

along posterior margin. Telson as long as broad; cleft entirely; 2 or 3 apical spines per lobe present,

these are 0.2* telson length, each accompanied by setae. Antennae (Figs 4A, 5A-B). Antenna 1 0.65x

of body length; main flagellum with up to 30-32 articles; almost all flagellar articles bearing small

aesthetascs accompanied by 2-8 short setae; peduncular articles in ratio 1:0.7:0.4; proximal article of

peduncle with 3 sets of short setae along ventral margin; accessory flagellum 3- or 4-articulated. Length

ratio of antenna 1 to antenna 2 is 1:0.5; flagellum of antenna 2 with 11-15 articles, each article densely

setose; length ratio of peduncle articles 4 and 5 is 1:0.9; flagellum as long as peduncle (articles 4+5);

peduncular articles 4 and 5 with sets of long stiff setae along ventral margin; gland cone short.

Mouth parts (typical gammarid. Figs 5E-G). Maxilla 1 palp longer than outer plate, distal article with

5 apical and 2 sub-apical setae (both palps asymmetric, right palp broader, with 4-5 strong spines and 2

plumose setae on apex and 1-2 setae on outer margin); outer plate with 12-14 spines (5 poorly toothed

and 9 multi-toothed); inner plate trapezoidal, with 12 plumose setae. Foregut lateralia with 13 strong

pectinate spines and densely setose row of stiff setae.

Gnathopods 1-2 (Fig. 5C-D). Gnathopod 1: propodus almond-shaped, palm convex, with cutting margin

acanthaceous and 2x longer than posterior margin; along posterior margin two sets of simple setae;

antero-distal group of anterior margin with 10 setae; palmar margin with short, notched setae along outer

and inner faces, palmar angle undefined, a group of 10 distally-notched strong spines on both faces (with

2 strong mid-palmar spines in the place where tip of nail close); nail long, 0.25 x total length of dactylus,

1 seta along anterior margin, with 4 setules at hinge. Gnathopod 2: propodus small (compared to the

body) and slightly larger than propodus of gnathopod 1; propodus almond-shaped, palm convex, with

cutting margin acanthaceous and as long as posterior margin; posterior margin with 6 sets of stiff setae;

antero-distal group of anterior margin with 10 setae; palmar margin with short, notched setae along outer

and inner faces, palmar angle undefined, a group of 8 distally-notched strong spines on both faces (with

2 strong mid-palmar spines in the place where tip of nail close); dactylus similar to that of gnathopod 1.

Pleopods (Fig. 6A-B). Pleopods 1-3 sub-equal, each with 2 coupling setae (retinacula) accompanied by

1-3 stiff setae; peduncular articles fringed with long, thin setae; proximal article of inner rami fringed

with 4 setae. Pleopods 1-3 rami with 15-19 articles each.

Uropods (Figs 4A, 6C-F). Uropod 1 protopodite with 1 basofacial spine, 3 dorso-lateral spines and

2 dorso-medial spines; exopodite as long as endopodite; rami straight, with single spines along outer

margins; both with 5 spines apically and sub-apically (two of them strong). Uropod 2 endopodite slightly

shorter than exopodite. Uropod 3 protopodite with 3 groups of spines on apex; endopodite as long as

protopodite, with 1 spine and 7 long setae apically; exopodite 2-articulated, about 2.2x longer than

protopodite, with 3 groups of lateral spines, 6 groups of long simple setae along inner margin; proximal

article with 4 spines and about 10 long setae on apex, terminal article short, 0.09x as long as proximal

article, with 6 long simple setae sub-apically.

Discussion of affinities

Describing the monotypic genus Anopogammarus Derzhavin (1945) noted a lack of eyes in A. birsteini as

the only difference from the genus Gammarus and considered this feature characteristic. Later, Birstein

6 Ljovuschkin (1970) re-described Anopogammarus birsteini in detail and considered this species,

along with Metohia carinata Absolon, 1927, as derived from Gammarus , implying a subgeneric status

for the genera Anopogammarus and Metohia. However, according to their view, Zenkevitchia revazi

occupies an intermediate position between the specialized Zenkevitchia admirabilis and Gammarus

(Stock 1973). Subsequently, Karaman & Barnard (1979) transferred Z. revazi to Anopogammarus, based

on the non-moplike structure of maxilla 1 and reduced palps in the former species. Later, the same authors

SIDOROV D.A. et al. , New genus and species of Typhlogammaridae

(Barnard & Karaman 1980) again confirmed that Anopogammarus, along with the rest of the taxa placed

in the Family group 2 ( Typhlogammarus group, hypogean large gammarids) sensu Bousfield (1977),

has no strong distinction from the Gammarus-Echinogammarus group (see Barnard & Karaman 1980:

7-9). Ruffo (1995) and Karaman & Ruffo (1995), describing two genera of cavernicolous amphipods

{Albanogammarus and Sinogammarus from Albania and Southwest China, respectively), discussed the

position of the new taxa in depth and hypothesized an obvious affinity with Anopo gammar us.

The revision of the group cannot be considered as completed, because the genus Anopogammarus

is heterogeneous and needs to be split. We propose transferring Anopogammarus revazi to the genus

Zenkevitchia (Zenkevitchia revazi Birstein & Ljovuschkin, 1970, comb, resurr.) and to the newly

proposed group {sandroruffoi- group). The monotypic genus Anopogammarus based on Anopogammarus

birsteini Derzhavin, 1945, however, should be considered a component of the family Gammaridae. As

the above-mentioned authors, we believe that the monotypic genus Anopogammarus has an affinity

to Albanogammarus and Sinogammarus. This assumption is based on the following shared features:

the structure of the anterior margin of the cephalon (lateral interantennal lobes slightly subquadrate);

powerful dorsal armament of urosomal segments; antenna 1 with small aesthetascs in males (? lacking in

Albanogammarus ); calceoli on antenna 2 absent; article 1 of antenna 2 being rather large, bearing short

setae, and antennal gland cone short; structure of maxilla 1 (outer plate with multi-toothed non-falcate

spines and palps clearly asymmetric); uropod 3 long and with 2-articulated outer ramus.

Family Typhlogammaridae Bousfield, 1978

Genus Zenkevitchia Birstein, 1940

Zenkevitchia Birstein, 1940: 51, fig. 4.

Zenkevitchia — Birstein 1941: 260, figs 1-3; 1950: 356. — Derzhavin 1945: 34. — Birstein &

Tjovuschkin 1970: 1472, fig. 1. —Bousfield 1977: 291. —Barnard & Barnard 1983: 507.

sun droruffoi -group

Remarks

Although, as described below, Zenkevitchia sandroruffoi sp. nov. differs from other species of

Zenkevitchia (Z. admirabilis , Z yakovi ) in the non-filtrative maxilla 1, we decided that it, along with

Z revazi , differs sufficiently to warrant recognition as a new species group within the genus Zenkevitchia ,

which we here designate as the sandroruffoi- group. The sandroruffoi- group (Z. sandroruffoi sp. nov.

and Z. revazi Birstein & Tjovuschkin, 1970) is phenotypically more distant from the type species of

the genus Zenkevitchia, bearing only up to 22 multi-toothed spines (non-falcate in shape). In some

sense, the group occupies an intermediate position between Zenkevitchia {admirabilis- group) and other

species of the Typhlogammaridae (cf. Accubogammarus ), although, in our opinion, it is closer to the

former. The indicators for affinity to Zenkevitchia are: interantennal cephalic lobes sub-acute, urosomal

segments weakly armed, shortened antenna 1, antennal gland cone of antenna 2 long, reduced and sub-

symmetrical palps of maxilla 1, structure and armament of gnathopods (both appendages with well-

defined palmar angle).

Despite these points of similarity, Z revazi needs re-description because some features, such as sexual

dimorphism, were not described properly, although important characters that clearly differentiate both

species (characteristics of Z. sandroruffoi sp. nov. in parentheses in the following list) are evident.

These are: outer plate of maxilla 1 with 11 spines (22 spines), palps of maxilla 1 asymmetric, reduced

(sub-symmetric, cf. Typhlogammarus m. mrazeki Schaferna, 1907 and T. m. heteropalpus Karaman,

1972; Karaman 1972, 1988) body of mandibles compacted (elongated), bases ofpereopods 5-7 without

European Journal of Taxonomy 168 : 1-32 ( 2015 )

lobes (with extraordinary roundish postero-proximal lobes), uropod 3 well-developed, setose with

plumose setae (reduced, wealdy setose). Zenkevitchia revazi reveals a number of features in common

with Accubogammarus and the minor differences between these taxa (Karaman 1973, 1974, 1988) are

mainly related to the structure of uropod 3.

Zenkevitchia sandroruffoi sp. nov.

urn:lsid:zoobank.org:act:707E6585-8A2E-47BA-802A-8349FAAlAAA2

Figs 2, 4F-H, 7-11

Diagnosis (both sexes)

Robust, middle-sized species of gammarid-like habitus (sexual dimorphism wealdy pronounced, i.e.,

males usually larger than females, antenna 2 and both gnathopods sexually dimorphic). Antenna 1 short,

reaching 40% length of body; antenna 2 short, reaching about 60% length of antenna 1, gland cone long,

reaching half of peduncle of segment 4. Maxilla 1 inner plate triangular, with 16 plumose setae, outer

plate of non-filtration type (?scraper type), with 22 multi-toothed, comb-like spines; palps symmetrical

and reduced. Mandibular palp article 3 with 1 A group of 2 setae, 2 B setae, 13 D setae and 4 E setae.

Gnathopods 1-2 small, with propodus not larger than corresponding coxa; palmar angles of both

gnathopods defined, with a group of notched, strong corner spines; dactyli with 1 seta each along outer

margin, nails long. Pereopods 5-7 bases with distinct postero-proximal lobes; inner margin of dactyli of

pereopods 3-7 with 1 stiff, notched seta. Urosomites with dorsolateral groups of spines. Pleopods 1-3

with 2 coupling setae (retinacula), each accompanied with 1 seta (2+1). Uropod 1 rami sub-equal, outer

ramus scarcely shorter than inner ramus. Uropod 3 short, 0.3 x shorter than uropod 2, endopodite small,

0.6x shorter than exopodite. Telson with 1 or 2 distal spines per lobe. Coxal gills 2-7 stalked, triangular

or sacciforme, largest on gnathopod 2, successively smaller on pereopods 3 to 7, gill 7 the smallest.

Body length 6.0-8.3 mm (§), 8.0-12.5 ($).

Etymology

This species is named in honor of Professor Sandro Ruffo (Museo Civico di StoriaNaturale, Verona) for

his outstanding contribution in the field of Amphipoda systematics.

Material examined

Holotype

GEORGIA: sequenced 8.0 mm, Sarma Cave (43°4158 N, 40°3633 E, approx.), 2346 m a.s.l.,

Muzykalnyj meander (sampling depth -350 m), Arabika massif, Gagra District, Western Caucasus,

25 Aug. 2012, coll. E.E. Golubnichaya (X44041/Cr-1647-FEFU).

Paratypes

GEORGIA: S, 10.5 mm, § (oostegites developed, weakly setose), 8.3 mm, Sarma Cave (sampling depth

-230 m), 28 Aug. 2012, coll. E.E. Golubnichaya (X44042/Cr-1648-51-FEFU); $, 12.5 mm, TrojkaCave

(43°3933 N, 40°3625 E, approx.), 2333 m a.s.l., ~2-3 km SW of Sarma Cave (sampling depth -30 m), 27

Aug. 2012, coll. E.E. Golubnichaya; $ (oostegites developed, weakly setose), 6.3 mm, Orlinoe Gnezdo

Cave, (43°3855 N, 40°3637 E, approx.), 2126 m a.s.l., ~10 km SW of Sarma Cave (sampling depth -75

m), 15 Sep. 2011, coll. L.T. Kharlamova.

Additional material

GEORGIA: specimens measured, partially dissected and stored in different vials (l-ll/2sd-IBSS): 2

$$ with developed oostegites, weakly setose, 7.0 mm, 8.0 mm, Sarma Cave, Muzykalnyj meander

(sampling depth -350 m), 25 Aug. 2012, coll. E.E. Golubnichaya; 2 $$ with developed oostegites,

weakly setose, 6.0 mm, 7.0 mm, Orlinoe Gnezdo Cave, (sampling depth -75 m), 27 Aug. 2012, coll.

E.E. Golubnichaya.

SIDOROV D.A. et al., New genus and species of Typhlogammaridae

Differential diagnosis

Zenkevitchia sandrornffoi sp. nov. can easily be distinguished from the other cavemicolous

typhlogammarids by the discriminative humps on its pleonal segments. See ‘Remarks’ section under

sandroruffo z-group as well as the key below.

Fig. 7. Zenkevitchia sandroruffoi sp. nov. Holotype, S, 8.0 mm, X44041/Cr-1647-FEFU. A. Antenna

1. B. Antenna 2. C. Barbate seta with attached filamentous algae. D. Gnathopod 1. E. Gnathopod 2.

F-G. Palmar margins of gnathopods 1 and 2 propodi.

European Journal of Taxonomy 168 : 1-32 ( 2015 )

Fig. 8. Zenkevitchia sandroruffoi sp. nov. —A-E, G-K. Holotype, S, 8.0 mm, X44041/Cr-1647-FEFU.

A. Left mandible. B. Right mandible. C. Lower lip. D. Upper lip. E. Maxilla 1. G. Palp of right maxilla

1. H. Maxilla 2.1. Maxilliped. J. Inner plate of maxilliped, inn er face. K. Inner plate of maxilliped, outer

face. — F, L. Paratype, §, 8.3 mm, X44043/Cr-1649-FEFU. F. Outer plate of maxilla 1. L. Outer plate

of maxilliped.

SIDOROV D.A. et al., New genus and species of Typhlogammaridae

Fig. 9. Zenkevitchia sandroruffoi sp. nov. Holotype, 8.0 mm, X44041/Cr-1647-FEFU. A. Pereopod 3.

B. Pereopod 4. C. Pleopod 1. D-F. Coupling setae ofpleopods 1-3. G. Epimeral plates 1-3. H. Uropod 1.

I. Uropod 2. J. Uropod 3. K. Telson.

European Journal of Taxonomy 168 : 1-32 ( 2015 )

Description

Male (holotype)

Body length. 8.0 mm

General body morphology (Fig. 9G, K). Body smooth, with median and lateral, sparse, single setae,

lacking dorsal cuticular elements but with distinct humps on pleonal segments. Head as long as first

pereon segment; rostrum absent; inferior antennal sinus deep, rounded. Eyes absent. Urosomites 1-3

on dorsal surface with lateral spines and setae; armed with notched spines in the following manner: 1

(0-0), 2 (2-2), 3 (1-0-1). Epimeral plate 1: postero-ventral corner beveled; posterior and ventral margins

convex; 2 stiff setae along ventral margin, 1 seta along posterior margin. Epimeral plate 2: postero-

ventral corner acuminate; posterior margin convex; ventral margin convex; 1 stiff seta along ventral

margin, 2 setae along posterior margin. Epimeral plate 3: postero-ventral corner acuminate; posterior

margin straight; ventral margin straight; 1 stiff seta along ventral margin, 1 seta along posterior margin.

Telson: width:length ratio is 1:0.6; cleft entirely; 2 apical spines per lobe present, 0.3-0.4x telson

length, each accompanied by 1 or 2 plumose setae.

Antennae (Figs 2, 7A-B). Ante nn a 1 0.38x of body length; main flagellum with up to 23 articles; each

article with 5-9 short setae; peduncular articles in ratio 1:0.7:0.4; proximal article of peduncle distally

with 1 medial set of long setae; accessory flagellum 3-articulated. Length ratio of antenna 1 to antenna

2 is 1:0.6; flagellum of antenna 2 with 10 articles, each article densely setose; length ratio of peduncle

articles 4 and 5 is 1:0.8; flagellum 0.4x longer than peduncle (articles 4+5); peduncular articles 4 and 5

with sets of long, stiff setae on lateral and medial faces; gland cone long, reaching half of peduncle of

segment 4.

Mouth parts. Typical gammarid, except for unusual maxilla 1 (Figs 4H, 8A-E, G-L). Labrum rounded,

clypeus unfused, longer than broad. Inner lobes of labium absent, outer lobes broad with stiff curved setae

marginally, mandibular process distinct (narrow). Left mandible: incisor with 5 teeth, lacinia mobilis

with 4 teeth; between lacinia and molar a row of 14 serrate spines. Right mandible: incisor process with

4 teeth, lacinia mobilis bifurcate, with several small denticles, between lacinia and molar a row of 12

serrate spines; triturative molar process with long lanose seta. Mandibular palp article 2 slightly longer

than article 3 (distal); proximal palp article without setae; second article with 12 setae; distal article

narrowed, with 1 A group of 2 setae, 2 B setae, 13 D setae and 4 E setae. Maxilla 1 palp reduced, distal

article with 4 or 5 apical setae (both palps sub-symmetrical); outer plate with 22 multi-toothed spines;

inner plate triangular, with 16 plumose setae. Maxilla 2 inner plate smaller than outer one with, oblique

row of 11 plumose setae; both of them apically with numerous setae in two rows. Maxilliped palp article

2 narrow, with about 55 setae along inner margin; article 3 narrow, with 2 dense sets of setae on inner

face; article 4 (distal) with dorsal seta, bearing 5 setae at the nail base, nail shorter than pedestal; outer

plate with 15 flattened naked spines and 7 long plumose setae on apex (3 of them flattened); inner plate

with 3 strong spines (1 supplemental spine on medial face) and 8 stiff, naked setae on apex, 27 plumose

setae on ventral face, 10 stiff denticulate setae in 2 rows on dorsal face. Foregut lateralia with 15 strong

pectinate spines, with densely setose row of stiff setae.

Coxal plates, gills (Figs 7D-E, 9A-B, 10A-C). Coxal plate 1 of rectangular shape, antero-ventral

margin extended, with 3 setae. Coxal plate 2 of rectangular shape, antero-ventral margin narrowed, with

3 setae. Coxal plate 3 width:depth is 0.5:1, along antero-ventral margin with 2 setae. Coxal plate 4 of

sub-quadrate shape, width:depth is 0.9:1; posteriorly with prominent excavation, along ventral margin

6 setae. Coxal plates 5-7 progressively smaller towards the posterior. Coxal plates 5-6: only anterior

lobe well-developed; posterior margin pointed with 2 setae. Coxal plate 7 sub-triangular, anterior part

beveled, along posterior margin with 3 setae in shallow serration. Coxal gills 2-7 stalked, large but

progressively smaller towards the posterior; gills 2-A triangular, gills 5-7 saccular or irregularly ovoid.

SIDOROV D.A. et al., New genus and species of Typhlogammaridae

Gnathopods 1-2 (Figs 7D-G). Gnathopod 1: ischium with postero-distal set of 6 short setae. Carpus

0.4x length of basis and 0.56x length of propodus; anterior margin of carpus with 1 group of setae;

carpus posteriorly with 2 sets of lateral setae. Propodus sub-rectangular, palm straight, with cutting

margin smooth and shorter than posterior margin; along posterior margin 5 simple setae with 1 pair of

notched spines; anterior margin with 2 sets of setae, antero-distal group with 4 setae; palmar margin with

short, notched setae along outer and inner faces, palmar angle with a group of 4 distally-notched, strong

Fig. 10. Zenkevitchiasandroruffoi sp. nov. Holotype, 8.0 mm, X44041/Cr-1647-FEFU. A. Pereopod 5.

B. Pereopod 6. C. Pereopod 7.

European Journal of Taxonomy 168: 1-32 (2015)

corner spines on both faces; nail long, 0.4x total length of dactylus, 1 seta along anterior margin and 3

setules at hinge. Gnathopod 2: basis width:length is 0.34:1. Ischium with 2 sets of postero-distal setae.

Carpus 0.3 x length of basis and 0.56x length of propodus; anterior margin of carpus with 1 distal set of

setae; carpus posteriorly with 3 lateral sets of setae. Propodus small (compared to the body) and same

length as propodus of gnathopod 1; propodus sub-rectangular, palm straight, with cutting margin smooth

and shorter than posterior margin; posterior margin with 4 sets of stiff setae; anterior margin with 2 sets

of setae; antero-distal group with 5 setae; palmar margin with short, notched setae along outer and inner

faces, palmar angle with a group of 5 distally-notched, strong corner spines on both faces; dactylus

similar to that of gnathopod 1.

Pereopods 3-7 (Figs 9A-B, 10A-C). Lengths of pereopods 3-4 equal. Dactylus 4 0.5x propodus 4;

nail length 0.5x total dactylus length. Dactyli 3-4 with dorsal plumose seta; inner margin with 1 stiff

seta and 1 thin seta at hinge. Lengths of pereopods 5:6:7 is 0.9:1:0.9. Pereopod 7 length 0.47x body

length. Bases 5-7 narrowed distally; posterior margin with postero-proximal lobes; posteriorly marginal

serrations with stiff setae (with thin setae in basis 5); anteriorly 3 notched spines. Dactylus 7 length

0.37x propodus 7 length. Dactyli 5-7 with dorsal plumose seta; inner margin with 1 stiff, notched seta

and 1 thin seta at hinge.

Pleopods (Fig. 9C-F). Pleopods 1-3 sub-equal, each with 2 coupling setae accompanied by 1 stiff seta;

peduncular articles fringed with long, thin setae; proximal article of inner rami fringed with 3 bifurcate

setae. Pleopods 1-3 rami with 10-15 articles each.

Uropods (Figs 2, 9H-J). Uropod 1 protopodite without basofacial spine, with 3 dorso-lateral spines and

1 dorso-medial spine; exopodite: endopodite length is 0.95:1; rami straight and unarmed along outer

margins; both with 5 strong, notched spines apically and sub-apically. Uropod 2 exopodite slightly

curved and 0.2x shorter than endopodite. Uropod 3 protopodite with 2 groups of strong notched spines

on apex; endopodite 0.4x of protopodite length, with 3 long setae apically; exopodite 1.16x longer than

protopodite, with 2 groups of lateral spines, long simple setae along inner margin, 3 spines and 4 setae

apically.

Female (paratype X44043/Cr-1649-FEFU)

Body length 8.3 mm, with sexually dimorphic characters (Fig. 11). Smaller than male, with more slender

body. Antenna 2 slender, peduncular article 4 with bundle of long setae on distal margin. Gnathopods

1 and 2: bases slender, with densely setose posterior margin; propodi sub-similar, sub-rectangular, but

propodus of gnathopod 2 larger than on gnathopod 1; palmar margins sub-transverse, palm straight,

with cutting margin acanthaceous; nail very long, 0.5x total length of dactylus. Uropod 3 weakly armed;

endopodite with 2 long setae apically. Telson with 1 spines per lobe. Oostegites 2-5 on gnathopod 2 and

pereopods 3-5, very broad, with marginal setae.

Variability

Flagellum of antenna 1 with 21-23 articles. Uropod 3 endopodite with 2-3 setae apically. One individual

had an abnormal 2-articulated accessory flagellum. The population of Z sandroruffoi sp. nov. inhabiting

streams in the Orlinoe Gnezdo cave differs slightly by having a smaller body size and further shortened

antenna 1, but are otherwise indistinguishable.

Ontogenetic variation

Almost all adults presented with significantly threadbare (Fig. 8F) or broken spines on the outer plate of

maxilla 1. Thus, the first three of the most powerful spines turned out to be broken off in almost of all

of the specimens.

SIDOROV D.A. et al., New genus and species of Typhlogammaridae

Fig. 11. Zenkevitchia sandroruffoi sp. nov. Paratype, 8.3 mm, X44043/Cr-1649-FEFU. A. Antenna 1.

B. Antenna 2. C. Gnathopod 1. D. Gnathopod 2. E-F. Palmar margins of gnathopods 1 and 2 propodi.

G. Uropod 1. H. Uropod 2. I. Uropod 3. J. Telson.

European Journal of Taxonomy 168: 1-32 (2015)

Distribution and ecology

Zenkevitchia sandroruffoi sp. nov. inhabits aquatic biotopes in several caves (Fig. 1) in the Eastern

Arabika massif and it apparently avoids deep cave habitats. This species was observed in the Sarma

Cave not deeper than -350 m (Fig. 2), in the nearby Trojka cave at a depth of -30 m and in the not-

far distant Orlinoe Gnezdo cave at -75 m. The setae on the antennal appendages of all specimens

were densely covered (Fig. 7C) with attached filamentous algae (cyanobacteria?). The nature of the

morphological variability and divergence of COI gene sequences (pairwise distances <2.2%) suggests

that, in the Orlinoe Gnezdo cave, the other population of the same species is present.

Genus Adaugammarus gen. nov.

um:lsid:zoobank.org:act:C38A81BD-4918-46B0-BD37-4BF7A6669E8F

Type species

Adaugammaruspilosus sp. nov., by monotypy.

Generic diagnosis

Stout and gentle, large-sized species of gammarid-like habitus (sexual dimorphism marked, i.e., some

males larger than females, antenna 2, both gnathopods and uropods 1-3 sexually dimorphic). Antenna

1 short, reaching 50% length of body; antenna 2 short, reaching about 50% length of antenna 1, gland

cone short. Maxilla 1 inner plate trapezoidal, with 10 plumose setae, outer plate of non-filtration type

(?scraper type), with 14 multi-toothed, comb-like spines; palps asymmetric and long. Mandibular palp

article 3 with 2 A groups, 2 B groups, 13 D setae and 4 E setae. Gnathopods 1-2 relatively small,

with propodus not larger than corresponding coxa; palmar angles of both gnathopods undefined, each

bearing a group of notched, strong palmar spines; dactyli with 1 seta along outer margin, nails rather

long. Pereopods 5-7 bases distinctly broader in proximal part; inner margin of dactyli of pereopods 3-7

with 1 stiff seta. Urosomites with dorsolateral groups of spines. Pleopods 1-3 with 2 coupling setae

(retinacula), each accompanied by 1 seta (2+1). Uropods 1-3 extremely setose, with dense bundles of

long swirling setae; uropod 1 exopodite broad and curved; uropod 3 exopodite broad, 1.6x longer than

protopodite (in males). Telson with 1 or 2 distal spines per lobe. Coxal gills 2-7 stalked, triangular or

sacciforme, largest on gnathopod 2, successively smaller on pereopods 3 to 7, gill 7 the smallest. Body

length 12.5-16.5 mm ($$), 11.5-17.5 ($$).

Etymology

The generic epithet ( Adaugammarus ) is derived by the combination of Adau , the name of fearsome

malicious giants in Abkhazian mythology, with Gammarus, a closely related genus. Gender masculine.

Discussion of affinities

Adaugammarus gen. nov. is an interesting taxon possessing features typical for a number of groups,

but tending more towards Typhlogammarus because of the following characters: lateral cephalic lobe

with recess, propodi of both gnathopods with palmar angles undefined, uropod 3 exopodite distinctly

broad in males. Adaugammarus gen. nov. is related to the sandroruffoi- group of Zenkevitchia and

Typhlo gammarus in the similar structure of the outer plate, which has 14 multi-toothed spines. The

urosomal segments are armed in a similar manner to those of Zenkevitchia. Adaugammarus gen. nov.

differs from Metohia in the absence of dorsal cuticular elements and from Accubogammarus in having

a short antennal gland cone, in variramus uropod 3, and differs in having 14 multi-toothed spines on the

outer plate of maxilla 1, in contrast to the 38 very densely toothed spines present in Accubo gammarus.

Superficial comparison with the other “deep dweller”, cf. Zenkevitchia sp. sensu Jaume in Sendra &

Reboleira (2012) from the Krubera-Voronja cave, revealed that the two taxa differ significantly from

each other by the body shape and by the extremely large body size (-19.0-28.0 mm in females from

Krubera) (pers. obs.).

SIDOROV D.A. et al ., New genus and species of Typhlogammaridae

Adaugammarus pilosus gen. et sp. nov.

urn:lsid:zoobank.org:act:356488CF-429D-4F6D-AD07-2E04A8E659Fl

Figs 2, 4I-K, 12-16

Diagnosis (both sexes)

As for the genus. A. pilosus gen. et sp. nov. is readily distinguished from the other cavemicolous

typhlogammarids by the sexually dimorphic uropods. See the section ‘Discussion of affinities’ and the

key below.

Etymology

The species epithet ( pilosus , Latin), meaning “covered with hairs”, refers to the extremely setose uropods

in males.

Material examined

Holotype

GEORGIA: sequenced $ (carrying 10 eggs), 13.5 mm, Sarma Cave (43°4158 N, 40°3633 E, approx.),

2346 m a.s.l., Transsib meander (sampling depth -1270 m), Arabilca massif, Gagra District, Western

Caucasus, 15 Sep. 2011, coll. P.V. Rudko (X44046/Cr-1652-FEFU).

Paratypes

GEORGIA: S, 11.5 mm, § (oostegites developed, setose), 12.5 mm, 5 (carrying 21 eggs), 16.5 mm,

same data as holotype; S, 17.5 mm, Sarma Cave, pit K25 Vodoprovod, (sampling depth -1700 m), 21

Sep. 2011, coll. P.V. Rudko (X44047/Cr-1653-55-FEFU).

Description

Holotype

Body length. 13.5 mm

General body morphology (Figs 2, 4I-J, 14C, G). Body smooth, with median and lateral thin setae,

lacking dorsal cuticular elements (keel or tubercles). Head shorter than first pereon segment; rostrum

indistinct; lateral cephalic lobe with recess; inferior antennal sinus shallow, sub-rounded. Eyes absent.

Urosomites 1-3 on dorsal surface with lateral spines and setae; armed with notched spines in the

following manner: 1 (0-0), 2 (1-1), 3 (1-0-1). Epimeral plate 1: postero-ventral comer prominent;

posterior and ventral margins convex; 3 stiff setae along ventral margin, 5 setae along posterior margin.

Epimeral plate 2: postero-ventral corner prominent; posterior margin straight; ventral margin convex; 3

stiff setae along ventral margin, 3 setae along posterior margin. Epimeral plate 3: postero-ventral corner

prominent; posterior margin straight; ventral margin convex; 3 stiff setae along ventral margin, 1 seta

along posterior margin. Telson: width: length ratio is 0.9:1; cleft 0.9 of length; 2 apical spines per lobe,

each accompanied by 2 setae.

Antennae (Figs 2, 12A-B). Ante nn a 1 0.5x of body length; main flagellum with up to 34 articles; each

article with 2-7 setae; peduncular articles in ratio 1:0.6:0.4; accessory flagellum 4-articulated. Length

ratio of antenna 1 to antenna 2 is 1:0.5; flagellum of antenna 2 with 13 articles, each article densely

setose; length ratio of peduncle articles 4 and 5 is 1:0.9; flagellum 0.2x longer than peduncle (articles

4+5); peduncular articles 4 and 5 densely setose, with tight bundles of long stiff setae on lateral and

medial faces; gland cone very short.

Mouth parts (typical gammarid, Figs 4K, 13). Labrum rounded, clypeus unfused, longer than broad.

Inner lobes of labium absent, outer lobes broad, with stiff curved setae marginally, mandibular process

distinct (narrow). Left mandible: incisor with 5 teeth, lacinia mobilis with 4 teeth; between lacinia and

European Journal of Taxonomy 168: 1-32 (2015)

molar a row of 11 serrate spines. Right mandible: incisor process with 4 teeth, lacinia mobilis bifurcate,

with several small denticles, between lacinia and molar a row of 9 serrate spines; triturative molar

process with long plumose seta. Mandibular palp article 2 longer than article 3 (distal); proximal palp

article without setae; second article with 21 setae; distal article narrowed, with 2 A groups of 2 and 7

Fig. 12. Adaugammarus pilosus gen. et sp. nov. Holotype, §, 13.5 mm, X44046/Cr-1652-FEFU.

A. Ante nn a 1. B. Ante nn a 2. C. Gnathopod 1. D. Gnathopod 2. E-F. Palmar margins of gnathopods 1

and 2 propodi (setation omitted).

SIDOROV D.A. et al., New genus and species of Typhlogammaridae

Fig. 1 3. Adaugammaruspilosus gen. et sp. nov. Holotype, $, 13.5 mm, X44046/Cr-1652-FEFU. A. Left

mandible. B. Right mandible. C. Article 3 of mandibular palp, ventral setation. D. Upper lip. E. Lower

lip. F. Maxilla I. G. Outer plate of maxilla 1. H. Palp of right maxilla L I. Maxilla 2. J. Maxilliped.

K. Inner plate of maxilliped, inner face. L. Inner plate of maxilliped, outer face. M. Outer plate of

maxilliped.

European Journal of Taxonomy 168: 1-32 (2015)

setae, respectively, 2 B groups of 3 and 4 setae, respectively, 13 D setae and 4 E setae. Maxilla 1 palp

long, distal article with 1 or 3 apical spines accompanied with setae (both palps asymmetric, right palp

broader, with 1 seta on outer margin); outer plate with 14 multi-toothed spines; inner plate trapezoidal,

with 10 plumose setae. Maxilla 2 with both plates narrowed, inner plate with oblique row of 8 plumose

setae; both of them apically with numerous setae in two rows. Maxilliped palp article 2 broad, with

Fig. 14. Adaugammarus pilosus gen. et sp. nov. Holotype, §, 13.5 mm, X44046/Cr-1652-FEFU.

A. Pereopod 3. B. Pereopod 4. C. Epimeral plates 1-3. D. Uropod I. E. Uropod2. F. Uropod 3. G. Telson.

SIDOROV D.A. et al., New genus and species of Typhlogammaridae

Fig. 15. Adaugammarus pilosus gen. et sp. nov. Holotype, 13.5 mm, X44046/Cr-1652-FEFU.

A. Pereopod 5. B. Pereopod 6, part. C. Pereopod 7. D. Pleopod 1. E-G. Coupling setae ofpleopods 1-3.

European Journal of Taxonomy 168: 1-32 (2015)

about 75 setae (some of them in 8 oblique clusters) along inner margin; article 3 narrow, densely setose,

with long setae on inner face; article 4 (distal) with dorsal seta, bearing 5 setae at nail base, nail half as

long as pedestal; outer plate with 18 flattened, naked spines, 2 long serrate spines and 3 long plumose

setae on apex; inner plate with 3 strong spines (1 supplemental spine on medial face) and 13 stiff, naked

setae apically and sub-apically, 24 plumose setae on ventral face, 5 stiff denticulate setae on dorsal face.

Foregut lateralia with 17 strong pectinate spines, with densely setose row of stiff setae.

Coxal plates, gills and oostegites (Figs 12C-D, 14A-B, 15A-C). Coxal plate 1 of rectangular shape,

antero-ventral margin extended, with sparse setae. Coxal plate 2 of sub-rectangular shape, antero-ventral

margin narrowed with, sparse setae. Coxal plate 3 width: depth is 0.5:1, antero-ventral margin narrowed,

with 3 setae. Coxal plate 4 of sub-quadrate shape, as long as broad; posteriorly with broad excavation;

along ventral margin sparse setae. Coxal plates 5-7 progressively smaller towards the posterior; coxal

plates 5-6 with anterior lobe well-developed; posterior margin pointed, with 4 or 5 setae. Coxal plate 7

sub-rectangular, along posterior margin 3 setae in shallow serration. Coxal gills 2-7 stalked, large but

progressively smaller towards the posterior; gills 2-4 sub-triangular, gills 5-7 saccular or irregularly

ovoid. Oostegites 2-5 on gnathopod 2 and pereopods 3-5, very broad, with long marginal setae.

Gnathopods 1-2 (Figs 12C-F). Gnathopod 1: ischium broadly setose, with stiff setae on distal and lateral

margins. Carpus 0.36x length of basis and 0.4x length of propodus; anterior margin of carpus with 1

group of setae; carpus posteriorly with transverse row of lateral and marginal setae. Propodus almond-

shaped, palm convex, with cutting margin smooth and longer than posterior margin; along posterior

margin a row of simple setae; anterior margin with 3 sets of setae, antero-distal group with 10 setae;

palmar margin with short, notched setae along outer and inner faces, palmar angle undefined, a group

of 10 distally-notched, strong spines on both faces (with 2 strong mid-palmar spines in the place where

tip of nail close); nail long, 0.4x total length of dactylus, 1 seta along anterior margin, without setules at

hinge. Gnathopod 2: basis width: length is 0.3:1. Ischium broadly setose, with stiff setae on distal and

lateral margins. Carpus 0.27x length of basis and 0.4x length of propodus; anterior margin of carpus

with 1 distal set of setae; carpus posteriorly with 5 lateral sets of setae and transverse row of marginal

setae. Propodus small (compared to the body) and same length as propodus of gnathopod 1; propodus

pyriform, palm convex with cutting margin smooth and shorter than posterior margin; posterior margin

with 8 sets of stiff setae; anterior margin with 5 sets of setae; antero-distal group with 10 setae; palmar

margin with short, notched setae along outer and inner faces, palmar angle undefined, a group of 5-6

distally-notched, strong spines on both faces in the place where tip of nail close (with 1 strong mid-

palmar spine); dactylus similar to that of gnathopod 1.

Pereopods 3-7 (Figs 14A-B, 15A-C). Lengths of pereopods 3^\ is 0.95:1. Dactylus 4 0.5x propodus 4;

nail length 0.5x total dactylus length. Dactyli 3-4 with dorsal plumose seta; inner margin with 1 stiff

seta and 1 thin seta at hinge. Lengths of pereopods 5:6:7 is 0.9:1:0.9. Pereopod 7 length 0.5x body

length. Bases 5-7 narrowed distally; length: width is 1:0.5-0.6; posterior margin curved (distinctly in

basis 7), without postero-distal lobes; marginal serrations with short setae posteriorly (expressed in

basis 5); 3-4 notched spines anteriorly. Dactylus 7 length 0.28 x of propodus 7 length. Dactyli 5-7 with

dorsal plumose seta; inner margin with 1 stiff seta and 1 thin seta at hinge.

Pleopods (Fig. 15D-G). Pleopods 1-3 sub-equal, each with 2 coupling setae accompanied by 1 stiff

seta; peduncular articles fringed with long, thin setae; proximal article of inner rami fringed with 5

simple setae. Pleopods 1-3 rami with 19-21 articles each.

Uropods (Figs 2, 14D-F). Uropod 1 protopodite with 1 basofacial spine, 2 dorso-lateral spines and 3

dorso-medial spines; exopodite: endopodite length is 1:0.8; rami straight, with single spines along outer

margins; both with 5 spines apically and sub-apically (two of them strong). Uropod 2 exopodite 0.2x

SIDOROV D.A. et al ., New genus and species of Typhlogammaridae

shorter than endopodite. Uropod 3 protopodite with 2 groups of spines on apex; endopodite 0.7x of

protopodite length, with 2 spines and 6 long setae apically; exopodite 1.3 x longer than protopodite, with

3 groups of lateral spines, long simple setae along inner margin, 3 spines and about 13 setae apically.

Male (paratype X44049/Cr-1655-FEFU)

Body length 17.5 mm, with sexually dimorphic characters (Fig. 16). Larger than female, with more stout

body. Antenna 2 densely setose. Gnathopods 1 and 2 propodi sub-similar, almond-shaped, but propodus

of gnathopod 2 larger than propodus of gnathopod 1; palmar margins beveled, palm straight, with

Fig. 16. Adaugammarus pilosus gen. et sp. nov. Paratype X44049/Cr-1655-FEFU, S, 17.5 mm. A.

Gnathopod 1, part. B. Gnathopod 2, part. C. Uropod 1. D. Uropod 2. E. Uropod 3. F. Telson.

European Journal of Taxonomy 168: 1-32 (2015)

Table 2. Estimates of pairwise sequence divergence (uncorrected p-distances) of partial mitochondrial

COI gene among and within species (bold type) of the Balkan and Caucasian Typhlogammaridae.

Numbers in brackets correspond to geographic locality on Fig. 1; n/a = not applicable.

Species

Number of

sequences

7 8

1 . Zenkevitchia sandroruffoi [1]

0.0034

2. Adaugammarus pilosus [2]

0.159

0.0009

3. Zenkevitchia yakovi [5]

0.142

0.141

0.0024

4. Metohia carinata

0.245

0.235

0.237

n/a

5. Typhlogammarus mrazeki

0.241

0.246

0.243

0.217

n/a

6. Typhlogammarus sp.

0.247

0.234

0.248

0.217

0.138

n/a

7. Zenkevitchia admirabilis [4]

0.138

0.150

0.128

0.239

0.233

0.247

0.0783

8. Zenkevitchia revazi [6]

0.206

0.210

0.255

0.246

0.251

0.207 n/a

cutting margin acanthaceous; nail short, 0.3x total length of dactylus. Uropods 1-3 extremely setose.

Uropod 1 protopodite with 3 sets of long setae along inner margin; exopodite broad and curved, longer

than endopodite; rami setose, with dense bundles of long, swirling setae. Uropod 2 protopodite with 5

sets of long setae along inner margin; exopodite as long as endopodite; rami setose, with dense bundles

of long, swirling setae. Uropod 3 protopodite with 5 sets of long setae along inner margin; endopodite

1.3x longer than protopodite, with 2 spines along inner margin and 2 spines on apex; exopodite broad,

1.6x longer than protopodite, with 3 groups of lateral spines, 3 spines on apex; rami setose, with dense

bundles of long, swirling setae.

Variability

Not observed.

Distribution and ecology

Adaugammarus pilosus gen. et sp. nov. inhabits aquatic biotopes in the Sarma Cave (Figs 1-2) in the

eastern Arabilca massif (species was observed at depths of -1270 m and -1700 m) and revealed an ability

to move in a hygropetric zone.

Phylogenetic analysis

To access the affinities of the newly described taxa and confirm their genetic distinctness, we sequenced

a partial mt -coxl gene from Z sandroruffoi sp. nov. (6 accessions. Table 1) and Adaugammarus gen. nov.

(4 accessions) and assembled a data set including their putative relatives, Accubogammarus , Metohia ,

Typhlogammarus, and Zenkevitchia spp. (Table 1). Specimens of Zenkevitchia sandroruffoi sp. nov.

from the Trojka (-30 m depth) and Sarma caves (-350 m) produced identical sequences (KT427522

and KT427521, respectively), as did two further specimens from the Orlinoe Gnezdo cave (-75 m;

KT427523 and KT427524); the intraspecific distance is 0.34 ± 0.17 SE (Table 2). All four specimens

of Adaugammarus pilosus gen. et sp. nov. from the deepest part of the Sarma Cave (-1270 to -1700 m;

KT427516 -KT427519) were also almost identical in sequence; the intraspecific distance is 0.09 ± 0.09

SE (Table 2). Redundant sequences were excluded from the analyses. The resulting topology (Fig. 3)

was generally in agreement with that previously obtained for a smaller data set (Sidorov et al. 2015).

Species of Zenkevitchia were members of a clade (81% BP) that also included Accubogammarus and

Adaugammarus gen. nov. Topologically, Z. revazi was a basal divergence in this lineage. Adaugammarus

gen. nov. was resolved as a sister (96%) to a cluster composed of Z. sandroruffoi sp. nov., Z. admirabilis ,

and Z. yakovi. The branching pattern among these species remained unresolved. Four highly similar

SIDOROV D.A. et al. , New genus and species of Typhlogammaridae

(/9-distances 0.002-0.01) Z sandroruffoi formed a robust (100%) clade characterized by a relatively

long branch. Accessions from the Sarma and Trojka caves shared two synapomorphic substitutions and

were clustered together to the exclusion of specimens from Orlinoe Gnezdo.

Discussion

Brief observation on the vertical distribution of Amphipoda in the Sarma cave

An integrated comparative morphological and genetic analysis of the new amphipod taxa in the Sarma

Cave revealed their obvious dissimilarity, which in turn allows us to pay attention to the structure of

this cave. The system of the Sarma Cave is heterogeneous in its physical structure. Following Burmak

(unpubl.) there are three parts: upper, middle and lower. In the upper part, down to -350 m, Z sandroruffoi

sp. nov. was discovered; in the lower part, down to -1700 m, A. pilosus was present. In the middle part

amphipods were not detected, but we can’t exclude that they were overlooked. In the lower level (from

-900 m to -1100 m) in the zone of major faulting leading to the deepest part, the cave abruptly changes

direction (see Fig. 2). In this part of the cave thick deposits of red clay are observed. There is also a

strong flowing stream in this part of the cave.

Zenkevitchia sandroruffoi sp. nov. is not endemic to the Sarma Cave and was noted in two other caves.

The most remote of the investigated caves, Orlinoe Gnezdo, is located about 3.5 km to the south of

Sarma. This suggests that Z. sandroruffoi sp. nov. is vagile, settling in suitable biotopes in the eastern

Arabika massif. The affinity of Z. sandroruffoi sp. nov. to the Zenkevitchia lineage and its limited

distribution suggest a relatively young phylogenetic age of this species. In contrast, A. pilosus is, in our

view, morphologically closer to Typhlogammarus and hence its cohabitation with Z. sandroruffoi sp.

nov. in the same cave at different depths is apparently not a result of parapatric speciation. Although

there are no reliable data about the geophysical structure and history of the Sarma Cave, it seems that

the lower part of the cave belongs to another speleological system, probably older than the overlying

cave system.

Key to the genera of Typhlogammaridae

1 Pleosomal (abdominal) segments 1-3 with a pair of bilateral teeth dorsally ... Metohia Absolon, 1927

- Pleosomal segments without teeth.2

2 Uropods in males setose with bundles of stiff, long setae. Adaugammarus gen. nov.

- Uropods ordinary.3

3 Antennal gland cone short. Typhlogammarus Schaferna, 1907

- Ante nn al gland cone long .4

4 Maxilla 1 outer plate filtrative, multisetose. Zenkevitchia ( admirabilis-g roup)

- Maxilla 1 outer plate ordinary.5

5 Uropod 3 parviramous, with inner ramus half as long as outer ramus .

. Zenkevitchia (sandroruffoi-growp)

- Uropod 3 almost aequiramous, with inner ramus somewhat shorter.

. Accubogammarus G. Karaman, 1974

Acknowledgements

The authors are thankful to our fellow cavers Pavel Rudko, Lyasan Kharlamova (Siberian Federal

University, Krasnoyarsk) and Elena Golubnichaya (Vladivostok Caving Club) for collection of material

during the research expeditions “Arabika-2011” and “Arabilca-2012”, to Dmitry Palatov (Moscow

European Journal of Taxonomy 168 : 1-32 ( 2015 )

State University) for collecting specimens of Anopogammarus and forwarding samples to us, to Dr. T.

Krapp-Schickel (Zoologisches Forschungsmuseum Alexander Koenig, Bonn) for providing DAS with

literature, and to Dr. B. Sket (University of Ljubljana) and two anonymous reviewers for critically

reading and commenting on the manuscript. This study was supported by the Russian Foundation for

Basic Research project No. 15-54-4001 lAbha.

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Manuscript received. 25 September 2015

Manuscript accepted. 17 November 2015

Published on: 24 December 2015

Topic editor: Rudy Jocque

Desk editor: Kristiaan Hoedemakers

Printed versions of all papers are also deposited in the libraries of the institutes that are members of the

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Royal Museum for Central Africa, Tervuren, Belgium; Natural History Museum, London, United

Kingdom; Royal Belgian Institute of Natural Sciences, Brussels, Belgium; Natural History Museum of

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