http://dx.doi.org/10.5852/ejt.2013.55

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2013 • Leduc D.

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

Research article

um:lsid:zoobank.org:pub:65D6F5EB-4999-409D-BA73-3FBC2A1143CF

Two new free-living nematode species (Trefusiina: Trefusiidae) from

the Chatham Rise crest, Southwest Pacific Ocean

Daniel LEDUC

National Institute of Water and Atmospherie Researeh, Private Bag 14-901, Kilbimie, Wellington,

New Zealand, Email: [email protected]

um:lsid:zoobank.org:author:9393949F-3426-4EE2-8BDE-DEFFACE3D9BC

Abstract. Two new speeies of the family Trefusiidae, viz., Trefusia piperata sp. nov. and Trefusialaimus

idrisi sp. nov., are deseribed from the erest of the Chatham Rise, Southwest Paeifie Oeean (350 m water

depth). The present study provides the first speeies reeords for this family in the region. Trefusia and

Trefusialaimus eomprise twenty and three valid speeies, respeetively. A key to males of Trefusia is

provided.

Keywords. Trefusia piperata sp. nov., Trefusialaimus idrisi sp. nov.. New Zealand, eontinental slope,

diehotomous key, sandy sediment.

Leduc D. 2013. Two new free-living nematode species (Trefusiina: Trefusiidae) from the Chatham Rise crest.

Southwest Pacific Ocean. European Journal of Taxonomy 55: 1-13. http://dx.doi.org/10.5852/ejt.2013.55

Introduction

Recent studies show high levels of nematode alpha (local) and beta (turnover) diversity on the continental

slope of New Zealand (Eeduc et al. 2012 a, b). The systematics of several free-living marine nematode

taxa, however, remains unstudied in the region. One such taxon is the family Trefusiidae, for which no

species records exist to date (Eeduc & Gwyther 2008). Surveys of nematode communities on Chatham

Rise and Challenger Plateau suggest the presence of at least twelve Trefusiidae morphospecies (Eeduc et

al. 2012a; D. Eeduc unpublished data). The low density of most species in deep-sea habitats, however,

often impedes the description of new species (e.g., Miljutin et al. 2010).

Most records of Trefusia De Man, 1893 and Trefusialaimus Riemann, 1974 are from relatively coarse

(sandy) sediments (e.g., Riemann 1974; Keppner 1992; Van Gaever e/a/. 2004; Rierae/a/. 2010). Trefusia

has been recorded in a variety of deep-sea habitats such as manganese nodule deposits (Bussau 1993;

Miljutin et al. 2010), canyons (Vitiello 1970), and mounds (Van Gaever et al. 2004). Trefusialaimus is a

rare genus and, until now, had only been recorded from the Arctic Ocean (Filipjev 1946) and Northeast

Atlantic (Riemann 1974). Here, two new species, Trefusia piperata sp. nov. and Trefusialaimus idrisi

sp. nov., are described from sandy sediments on the continental slope of New Zealand.

European Journal of Taxonomy 55 : 1-13 ( 2013 )

Methods

Sediment samples were obtained from Chatham Rise, a submarine ridge that extends eastwards from the

South Island of New Zealand, from depths of ca. 250 to 3000 m. Samples were eolleeted in February

2011 during National Institute of Water and Atmospherie Researeh (NIWA) eruise TAN1103, from a

site near eentral Chatham Rise erest at a depth of 350 m (43.331° S, 178.288° E) (see Ledue & Pilditeh

2013 for details of sampling site).

A total of 15 sediment samples was eolleeted, using an Oeean Instruments MC-800Amultieorer (MUC;

eore internal diameter = 9.5 em). Samples were obtained from ten MUC deployments from the sampling

site. Eaeh sample eonsisted of one subeore of internal diameter 26 mm taken to a depth of 5 em. Cores

were split into 0-1, 1-3, and 3-5 em sediment depth layers, fixed in 10% formalin and stained with

Rose Bengal. Samples were subsequently rinsed on a 1 mm sieve to remove large partieles and on a

45 pm sieve to retain nematodes. Nematodes were extraeted from the remaining sediments by Eudox

flotation and transferred to pure glyeerol (Somerfleld & Warwiek 1996). Speeies deseriptions were made

from glyeerol mounts using differential interferenee eontrast mieroseopy (lO-lOOOx magnifleation) and

drawings were made with the aid of a eamera lueida. Measurements (in pm) were made using image

analysis software (eellSens Standard 1.6), and all eurved struetures are measured along the are. Type

speeimens are held in the NIWA Invertebrate Colleetion (NIC), Wellington.

Abbreviations

a = body length/maximum body diameter

abd = anal body diameter

b = body length/pharynx length

e = body length/tail length

ebd = eorresponding body diameter

E = body length

n = number of speeimens

%V = vulva distanee from anterior end of body x 100/total body length

Results

Family Trefusiidae Eorenzen, 1981

Diagnosis

Cutiele smooth or with faint striations. Metanemes absent. Amphid either spiral or non-spiral. Outer

labial sensillae and eephalie setae usually in two separate eireles (exeept in Trefusialaimus)', jointed

eephalie setae. Bueeal eavity funnel- or barrel-shaped, teeth absent. Males usually with two testes

(exeept Trefusialaimus) and females usually with two ovaries.

Genus Trefusia de Man 1893

Type species

Trefusia longicauda De Man, 1893

Diagnosis

Amphideal fovea eryptospiral, oval, or horse-shoe shaped. Funnel-shaped bueeal eavity. Males with

ventral (and sometimes subventral) longitudinal rows of eervieal sensillae. Small papillose pre-eloaeal

supplements present, situated either in a single ventral row or two sub-ventral rows; post-eloaeal papillae

LEDUC D., Two new nematode speeies from the SW Paeifie

absent. Spieules usually with handle-shaped proximal ends. Females with two ovaries. Tail eonieal,

eonieo-eylindrieal, or filiform.

Remarks

The last treatment of the genus Trefusia was by Keppner (1992), who provided an updated key to

the males of the 17 speeies of the genus based on Riemann (1966). T. varians Gerlaeh, 1955 was not

ineluded in the key beeause the original deseription was based on female speeimens only. Sinee then,

Trefusia monodelphis Bussau, 1990 was synonymised with Trichistoma gracile Andrassy, 1985 by

Andrassy (2007), and two new speeies were deseribed by Bussau (1993). There are eurrently 20 valid

Trefusia speeies (ineluding T piperata sp. nov.).

Trefusia piperata sp. nov.

Figs 1-2, Table 1

um:lsid:zoobank.org:aet:43C390C6-9807-4050-857F-02E4538D9920

Diagnosis and relationships

Trefusia piperata sp. nov. is eharaeterised by six double-jointed outer labial setae with eonspieuous

elusters of dark granules at their base, four eephalie setae at level of amphid, one seta posterior to eaeh

amphid, and long filiform tail. Male is eharaeterised by six eervieal papillae, eight papillose pre-eloaeal

supplements, slightly bent spieules, and gubemaeulum with funnel-shaped distal portion and pointed

projeetions.

Trefusia piperata sp. nov. most elosely resembles T helgolandica Riemann, 1966, deseribed from

subtidal sediments in the German Bight. The two speeies are similar in the shape and position of the

outer labial setae and eephalie setae, as well as in the strueture of the spieules and gubemaeulum. The

new speeies, however, differs from T helgolandica in head diameter (14-15 v^. 22-25), maximum body

width (21-22 > 33), spieule length (24 v^. 38), number of setae posterior to the amphids (one v^. two

or three), the number and shape of eervieal papillae (six papillae with wide base v^. thirteen papillae

without wide base), and number of pre-eloaeal supplements (eight v^. fourteen). Trefusia piperata sp.

nov. also differs from T helgolandica in the presenee of eonspieuous elusters of dark granules at the

base of the outer labial setae.

Etymology

The speeies name is derived from the latin word piperatus (= peppered), and refers to the eonspieuous

elusters of dark granules at the base of the eephalie setae.

Material examined

Holotype

S, eolleeted on 20 Feb. 2011 (NIWA emise TAN1103, station 69), eentral Chatham Rise (43.331° S,

178.288° E), water depth 350 m, sediment depth 1-5 em, mean grain size 55-59 pm, %sand 55-57%,

partiele sorting (geometrie) 4.1-4.3 (NIWA 88347).

Paratype

1 $, same data as holotype (NIWA 88348).

Description

Male

Body eylindrieal, slender, tapering slightly towards anterior extremity (Fig. 2C). Cutiele thin, < 1 pm

thiek, with very fine striations, diffieult to observe. Head blunt, slightly rounded, with three lips; six

European Journal of Taxonomy 55: 1-13 (2013)

Fig. 1. Trefusia piperata sp. nov. A. Anterior body region of female. B. Anterior body region of male.

C. Entire female. D. Right spieule and gubemaeulum. E. Posterior body region of male. Arrow shows

position of vulva. Seale bar: A-B, E = 20 pm; C = 75 pm; D = 8 pm.

LEDUC D., Two new nematode speeies from the SW Paeifie

small eonieal inner labial sensillae, ~1 pm long, six double-jointed outer labial setae with blunt ends, ca.

0.7 ebd (Fig. IB). Conspieuous elusters of dark brown granules situated at base of eaeh outer labial seta

(Fig. 2A). Four eephalie setae at level of amphid, jointed, 5-7 pm long (Fig. IB). Amphid poeket-shaped

with oval aperture, ca. 4 pm wide by 2 pm high. One seta situated ca. 25 pm posterior to eaeh amphid, 5

pm long. No other somatie setae observed. Six small eervieal papillae with wide base situated ventrally

in longitudinal row; row extends from posterior of amphid to about 60% of pharynx length from anterior

(Fig. IB). Bueeal eavity funnel-shaped, without teeth. Pharynx eylindrieal, slightly swollen at anterior

Fig. 2. Trefusia piperata sp. nov. Fight mierographs. A. Head region of male, showing bueeal eavity,

eephalie setae, and elusters of dark granules at base of outer labial setae. B. Spieule and gubemaeulum.

C. Entire male. Seale bar: A-B = 10 pm; C = 100 pm.

European Journal of Taxonomy 55: 1-13 (2013)

Table 1. Morphometries (pm) of Trefusiapiperata n. sp. and Trefusialaimus idrisi n. sp. (a: body length/

maximum body diameter, abd: anal body diameter, b: body length/pharynx length, e: body length/tail

length, ebd: eorresponding body diameter, V: vulva distanee from anterior end of body, %V: V/total

body length).

Species

Trefusiapiperata sp. nov.

Trefusialaimus idrisi sp. nov.

Holotype S

Paratype $

Holotype S

Paratype juv.

3663

4492

4539

2826

167

214

130

Head diameter*

Mouth diameter

Length of sub-eephalie setae

5-7

6-7

Length of eephalie setae

7-8

8-10

Amphid height

Amphid width

Amphid width/ebd (%)

Amphid from anterior end

Nerve ring from anterior end

119

117

111

152

Nerve ring ebd

Pharynx length

260

281

357

314

Pharyngeal bulb diameter

Pharyngeal bulb ebd

Max. body diameter

Spieule length

Gubemaeulum length

Anal body diameter

Tail length

1806

2330

650

590

Tail length/abd

155

1383

Vulval bodv diameter

*at level of eephalie setae

and posterior extremities, eompletely surrounds bueeal eavity. Nerve ring situated at ea. 45% of pharynx

length from anterior extremity. Seeretory-exeretory system not observed. Cardia very small.

Reproduetive system diorehie with outstretehed testes. Position of testes relative to intestine diffieult to

aseertain. Sperm eells drop-shaped with rod-shaped nueleus; vas deferens ca. 445 pm long. Paired, equal

spieules, slightly bent near distal one third, without obvious eentral eutieularised projeetion (i.e., lamella

or median rib). Gubemaeulum with narrow proximal region and funnel-shaped distal region with large

anterior pointed projeetion and smaller posterior pointed projeetion (Figs ID, 2B). Eight small papillose

pre-eloaeal supplements situated ventrally, 6-15 pm apart exeept for anterior-most supplement whieh

is situated 40 pm from next supplement. Tail very long, ca. half of total body length, filiform, without

setae, tightly eoiled.

Female

Similar to male, but with slightly shorter eephalie setae and slightly smaller amphid (Fig. lA). Female

reproduetive system didelphie, amphidelphie with refiexed ovaries. Position of ovaries relative to the

intestine diffieult to aseertain. Vulva situated at one third of body length (Fig. 1C).

LEDUC D., Two new nematode speeies from the SW Paeifie

Discussion

Trefusia piperata sp. nov. was rare at the study site, with only four speeimens (the two type speeimens

and two juveniles in poor eondition, eaeh from a different subeore) reeorded out of the 4412 individuals

that were identified by Ledue & Pilditeh (2013). Two individuals were found in the 1-3 em sediment

depth layers, and two were found in the 3-5 em sediment depth layer (D. Ledue, unpublished data).

Key to the males of Trefusia (modified from Keppner 1992):

1 Large eomplex sensillae present on ventral surfaee in eervieal region .2

- Large eomplex sensillae absent on ventral surfaee in eervieal region; small papilliform sensillae

may be present in eervieal region .3

2 Complex eervieal sensillae pyriform; spieules narrow, areuate; tail 7.4 abd long .

. T. honessi Keppner, 1986

- Complex eervieal sensillae eireular; spieules broad with bladder-like strueture on ventral side; tail 15-

17 abd long. T. americanaYjd^^nQX, 1992

3 Cirele of four eephalie sensillae distinetly anterior to amphid .4

- Cirele of four eephalie sensillae in region of, or posterior to amphid.8

4 Spieules 6.8-7.4 abd long; gubemaeulum present . T. filicauda AWgin, 1933

- Spieules less than 2.5 ebd; gubemaeulum present or absent .5

5 Amphid situated > 3 ebd from anterior extremity. T. attenuata Bussau, 1993

- Amphid situated < 3 ebd from anterior extremity .6

6 Amphid aperture eireular . T. dominatrix Bussau, 1993

- Amphid aperture oval .7

7 Amphid aperture transversely oval; tail 4.0 abd long . T. cornea Gerlaeh, 1958

- Amphid aperture longitudinally oval; tail 20 abd long . T. axonolaimoides Allgen, 1953

8 Tail short, eonieal, 1.0 abd long. T. conica Gerlaeh, 1957

- Tail long, eonieal to filiform, greater than 5.0 abd long.9

9 Gubemaeulum present .10

- Gubemaeulum absent.14

10 Gubemaeulum with lateral aeeessory pieee.11

Gubemaeulum without lateral aeeessory pieee . T. spatulata Keppner, 1992

11 Cirele of four sub-eephalie sensillae posterior to amphid; spieules with strong are .

. T. zostericola Allgen, 1933

Cirele of four sub-eephalie sensillae at level of amphid; spieules without strong are.12

12 Lateral pieee of gubemaeulum distinet; spieules without distinet outer median rib (lamella).13

Lateral pieee of gubemaeulum not distinet; spieules with distinet, outer, median rib; eervieal

region with single setiform postamphidial sensilla . T. longicauda De Man, 1893

13 Cervieal region with two or three setae posterior to eaeh amphid; male with longitudinal

row of 13 papillae in eervieal region; no elusters of dark granules at base of eephalie setae

. T. helgolandica Riemann, 1966

European Journal of Taxonomy 55: 1-13 (2013)

Cervical region with one seta posterior to each amphid; male with longitudinal row of six

papillae on wide base in cervical region; clusters of dark granules at base of cephalic setae

present . T. piperata sp. nov.

14 Cervical and pre-cloacal papilliform supplements present on ventral surface; c greater than 5.1

.15

Cervical and pre-cloacal papilliform sensillae absent from ventral surface; c = 2.8.

. T. pseudolittoralis Vitiello, 1970

15 Spicules slender, gently curved, capitulum not broad and elongate .16

Spicules broad, acutely curved, capitulum broad and elongate .17

16 Pre-cloacal papilliform sensillae 12-18 in number; a = 112-129.

. T. multipapillatum Bouwman, 1981

Pre-cloacal papilliform sensillae 5-7 in number; a = 70-87 . T. littoralis AWgQn, 1932

17 Capitulum of spicules with elongate ventral projection ...T. curvispiculosa Vincx & Vanreusel, 1989

Capitulum of spicules without elongate ventral projection .18

18 Circle of four sub-cephalic setae posterior to amphid; excretory pore heavily cuticularised; a = 88-117

. T. longicorpa Keppner, 1986

Circle of four sub-cephalic setae at level of amphid; excretory pore not observed; a = 53-57 .

. T. schiemeri Ott, 1977

Genus Trefusialaimus 1974

Type species

Trefusialaimus monorchis Riemann, 1974

Diagnosis

Sub-cephalic and somatic setae absent. Ten cephalic setae in one circle; amphid pocket-shaped. Male

with one testis and peri-cloacal papillae. Elongated sperm cells with central rod and light-refractive

nucleus at one extremity. Tail conico-cylindrical or filiform.

Trefusialaimus idrisi sp. nov.

Figs 3-4; Table 1

um:lsid:zoobank.org:act:56BDlB40-542A-4FE2-BB84-F8FC7C5C2667

Diagnosis and relationships

Trefusialaimus idrisi sp. nov. is characterised by relatively short body length, presence of numerous

golden inclusions in the chords, cephalic setae 0.65-0.80 cbd long, spicules 2.3 abd long, 4 pairs of peri-

cloacal papillae, and long, gradually tapering tail.

Until now, only two Trefusialaimus had been described, viz., T magnus (Filipjev, 1946) and T monorchis

Riemann, 1974. Trefusialaimus idrisi sp. nov. is similar to T magnus in the shape of the copulatory

apparatus and tail, but can be differentiated from the latter by the shorter body length (4540 v^. 7700

pm), lower value of c (7 v^”. 21), longer cephalic setae (0.65-0.80 vv 0.4 cbd), longer spicules (2.3 v^.

1.7 abd), and longer tail (38 v^. 11 abd). T idrisi sp. nov. can easily be differentiated from T monorchis

by the markedly longer cephalic setae (0.65-0.80 v^. 0.26 cbd), absence of pre- and post-cloacal papillae

(present in T monorchis), and tail shape (gradually tapering vv conico-cylindrical).

LEDUC D., Two new nematode speeies from the SW Paeifie

Fig. 3. Trefusialaimus idrisi sp. nov. A. Anterior body region of male. B. Head of male. C. Head of

juvenile. D. Right spieule. E. Gubemaeulum. F. Male eopulatory apparatus. G. Mature sperm. H.

Posterior body region of male. Seale bar: A = 40 pm; B-C, G = 20 pm; D-E = 14 pm; F = 28 pm; H =

75 pm.

European Journal of Taxonomy 55: 1-13 (2013)

Fig. 4. Trefusialaimus idrisi sp. nov. Light micrographs. A. Anterior body region of male, lateral view.

B. Anterior body region of juvenile, dorsal view. C. Mid-body region of juvenile, showing sperm eells

in pseudoeoelom. D. Entire male. E. Lateral ehord of male, showing round golden inelusions. Arrows

point to sperm eells. Seale bar: A-C, E = 15 pm; D = 260 pm.

LEDUC D., Two new nematode speeies from the SW Paeifie

Etymology

The speeies is named after Idris Matai Kljueanin Bmn, the author’s godson.

Material examined

Holotype

S, eolleeted on 20 Feb. 2011 (NIWA emise TAN1103, station 69), eentral Chatham Rise (43.331° S,

178.288° E), water depth 350 m, sediment depth 1-5 em, mean grain size 55-59 pm, %sand 55-57%,

partiele sorting (geometrie) 4.1-4.3 (NIWA 88349).

Paratype

1 juvenile, same data as holotype (NIWA 88350).

Description

Male

Body eylindrieal, slender, tapering slightly towards anterior extremity (Fig. 4D), with slight golden

eolouration due to the presenee of numerous round, ca. 1 pm diameter, golden inelusions in the

ehords (i.e., longitudinal thiekenings of the hypodermis protruding internally between the seetors of

the longitudinal museles; Chitwood & Chitwood 1974) (Fig. 4E). Cutiele smooth, thin, ca. 0.7-0.9 pm

thiek, exeept in head region (anterior to eephalie setae) where it is slightly thieker, 1.0-1.6 pm. Head

rounded, slightly set-off from body due to thiekened eutiele, with three lips, eaeh bearing two small,

eonieal inner labial papillae 1.0-1.5 pm long (Fig. 3B). Six outer labial setae and four eephalie setae

in one eirele, double-jointed; eephalie setae slightly longer than outer labial setae (0.75-0.80 ebd v^.

0.65 ebd). Sub-eephalie and somatie setae absent. Amphid poeket-shaped with oval aperture, ca. 6

pm wide by 2 pm high (Fig. 3A). Bueeal eavity funnel-shaped, without teeth. Pharynx eylindrieal,

slightly swollen at posterior extremity, eompletely surrounds bueeal eavity. Pharyngeal lumen lightly

but distinetly eutieularised at anterior extremity (Figs 3B, 4B). Nerve ring situated at ca. 50% of pharynx

length. Seeretory-exeretory system not observed. Cardia small.

Reproduetive system monorehie with single outstretehed testis, ca. 1960 pm long. Position of testis

relative to intestine diffieult to aseertain. Elongated sperm eells, ea 3-5 pm wide by 13-16 pm long, with

eentral rod and nueleus at one extremity (Fig. 3G); vas deferens ca. 520 pm long, without museular

ejaeulatory duet. Paired, equal spieules, 2.3 abd long, slightly bent near distal one third, with broad

proximal end and narrow pointed distal end; velum present (Fig. 3D). Gubemaeulum with two pairs of

narrow, pointed lateral erurae (Fig. 3E). Four pairs of small, eonieal peri-eloaeal papillae (Fig. 3F). Pre-

eloaeal supplements absent. Tail long, ca. 14% of total body length, narrow, gradually tapering, without

setae (Fig. 3H).

Juvenile

Similar to male, but with shorter and narrower body, shorter eephalie setae (Figs 3C, 4B), and smaller

amphid. Numerous sperm eells are present throughout the pseudoeoelom from ca. 90 pm posterior

to pharynx to ca. 200 pm anterior to anus (Fig. 4C). Genital and eopulatory (i.e., eloaeal or vulval)

primordia not observed.

Discussion

The presenee of sperm eells in the pseudoeoelom of the juvenile Trefusialaimus idrisi sp. nov. speeimen

is unusual. Some nematode speeies, sueh as Oncholaimus oxyuris, ean transfer sperm through traumatie

insemination (Coomans et al. 1988), a proeess whereby the male injeets sperm direetly into the body of a

female (or potentially even a male or juvenile) by piereing the eutiele with the spieules. The presenee of

sperm eells in the juvenile speeimen eould be explained if a similar proeess oeeured in T. idrisi sp. nov.

European Journal of Taxonomy 55: 1-13 (2013)

The existence of such a reproductive strategy, however, is highly conjectural because no Trefusialaimus

females have ever been observed and (to my knowledge) traumatic insemination has not been described

in the suborder Trefusiina.

Trefusialaimus idrisi sp. nov. was rare at the study site, with only four specimens (the two type specimens

and two juveniles in poor condition, each from a different subcore) recorded out of the 4412 individuals

that were identified by Leduc & Pilditch (2013). All individuals were found in the surface (0-1 cm)

sediment layer (D. Leduc, unpublished data). A single juvenile specimen (out of 4550 specimens

identified from 30 locations on the New Zealand continental margin) was recorded from a site on the

northern frank of Chatham Rise at a depth of 1000 m (178.500° E, 44.333° S; silt/clay content 95%)

(Leduc et al. 2012a; D. Leduc unpublished data).

Acknowledgements

Funding was provided by FRST through a postdoctoral fellowship to D. Leduc (UOOX0909), the

programme “Coasts & Oceans OBI” (CO 1X0501), andNlWAby Coasts and Oceans Centre Research

Programme 2 (2012/13 SCI). 1 am thankful to Scott Nodder (NIWA) for facilitating sample collection,

Keith Probert (University of Otago) for his support and guidance, Anna Lawless (University of Waikato)

for her help with processing of multicorer samples onboard RV Tangaroa, and Ann e-Nina Lorz for her

help with the translation of Riemann’s original species descriptions. 1 am grateful to two anonymous

reviewers for providing constructive criticisms on the manuscript. 1 also acknowledge the other

participants of voyage TAN 1103, and the officers and crew of RV Tangaroa.

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Manuscript received: 3 April 2013

Manuscript accepted: 26 July 2013

Published on: 5 September 2013

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 EJT eonsortium: Museum National d’Histoire Naturelle, Paris, Franee; National Botanie Garden

of Belgium, Meise, Belgium; Royal Museum for Central Afriea, Tervuren, Belgium; Natural History

Museum, Fondon, United Kingdom; Royal Belgian Institute of Natural Seienees, Brussels, Belgium;

Natural History Museum of Denmark, Copenhagen, Denmark.