European Journal of Taxonomy 87: 1-19
http://dx.doi.org/lQ.5852/ejt.2014.87
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2014 • Bostrom S. & Holovaehov O.
Research article
um:lsid:zoobank.org:pub:691BA51C-6882-4437-AQ37-QE8861DCBF17
Descriptions of species of Stegelleta Thorne, 1938
(Nematoda, Rhabditida, Cephalobidae) from California, New Zealand
and Senegal, and a revision of the genus
Sven BOSTROM' & Oleksandr HOLOVACHOV^
Department of Zoology, Swedish Museum of Natural History, Box 50007,
SE-104 05 Stoekholm, Sweden
^ Email: [email protected] (eonesponding author)
^ Email: [email protected]
i um:lsid:zoobank.org:author:528300CC-D0F0-4097-9631-6C5F75922799
^ um:lsid:zoobank.org: author: 89D30ED8-CFD2-42EF-B962-30A13F97D2Q3
Abstract. Populations of Stegelleta are deseribed from California, New Zealand and Senegal. An
amphimietie population from California is identified as belonging to S. incisa and eompared with
type speeimens from Utah and an amphimietie population from Italy. One population from New
Zealand is elose to S. incisa but eonsidered to represent a new speeies, Stegelleta laterocornuta
sp. nov. It is partieularly eharaeterised by a 379-512 pm long body in females and 365^76 pm in
males; eutiele divided into 16 rows of bloeks at midbody (exeluding lateral field); lateral field with
four ineisures; three pairs of asymmetrieal lips, U-shaped primary axils without guarding proeesses,
eaeh lip asymmetrieally reetangular with a smooth margin, only lateral lips have slender aeute tines;
three labial probolae, bifureated at half of their length; vulva without fiap; spermatheea 17-31 pm
long; postuterine sae 7-24 pm long; spieules 21.5-23.5 pm long. Other speeimens from New Zealand
are identified as belonging to S. tuarua. A parthenogenetie population from Senegal is identified as
belonging to S. ophioglossa and eompared with type speeimens from Mongolia and reeords of several
other populations of S. ophioglossa. The generie diagnosis is emended and a key to the speeies of
Stegelleta is provided.
Keywords. Morphology, new speeies, SEM, Stegelleta, taxonomy.
Bostrom S. & Holovaehov O. 2014. Descriptions of species of Stegelleta Thome, 1938 (Nematoda, Rhabditida,
Cephalobidae) from California, New Zealand and Senegal, and a revision of the genus. European Journal of
Taxonomy 87: 1-19. http://dx.doi.org/10.5852/ejt.2014.87
Introduction
The genus Stegella was ereeted by Thorne (1937) with Stegella incisa Thome, 1937 as type speeies,
for eephalobids having: eutiele divided into plate-like segments over entire body; labial probolae
fureate, prongs simple or with few branehes; eephalie probolae variable, rounded axil borders or
fiap-like with membranes; and wing area unusually broad with a medial line and erenate borders.
1
European Journal of Taxonomy 87 : 1-19 ( 2014 )
Due to a homonomy with a hydroid, Stegella Stechow, 1919, it was later renamed and beeame
Stegelleta Thorne, 1938. Stegelleta eurrently ineludes six valid speeies of whieh the most reeent
one, S. arenaria Bostrom & Holovaehov, 2012, was deseribed from Kelso Dunes, Mojave National
Preserve, California. Speeimens of S. incisa were also found in the samples from Kelso Dunes. This
population is here deseribed from studies by light (LM) and seanning eleetron mieroseope (SEM)
and eompared with type speeimens from Utah and an amphimietie population from Italy deseribed
under the name S. ophioglossa Andxkssy, 1967 (Thorne 1937; Orselli & Vineiguerra 2002). Another
population from New Zealand, deseribed here from studies by light and seanning eleetron mieroseope,
is elose to S. incisa but eonsidered to represent a new speeies. Some speeimens of S. tuarua Yeates,
1967 from New Zealand are also deseribed and eompared with the original deseription (Yeates 1967).
A reeent parthenogenetie population of S. ophioglossa from Senegal is deseribed and eompared with
the original deseription of S. ophioglossa from Mongolia and reeords of populations from Uzbekistan,
Senegal, Iran and Spain (Andrassy 1967; Mavljanov 1978; De Ley et al. 1990; Shokoohi et al. 2008;
Abolafia et al. 2011). The generie diagnosis is emended and a key to the speeies of Stegelleta is
provided.
Material and methods
During a tour in the Kelso Dunes area, Mojave National Preserve, southern California, the junior
author eolleeted several samples of sand underneath different speeies of desert plants. Nematodes were
reeovered from sand samples using a modified Baermann funnel extraetion. For LM, speeimens were
relaxed by gentle heat, fixed in eold 4% formaldehyde solution, transferred to pure glyeerine by a slow
evaporation method and mounted on permanent slides in glyeerine with paraffin wax as support for the
eoverslip. After measuring and observations, some speeimens were removed from slides and rehydrated
by first gradually adding drops of SI (1% glyeerine, 20% ethanol and 79% distilled water) to glyeerine
in an embryo-dish until the volume tripled and then gradually adding distilled water until the volume
tripled again. The speeimens were then washed in distilled water before resuspension in formaldehyde.
For SEM, speeimens were post-fixed in 1% osmium tetroxide (OsO^) and transferred to pure aeetone
through an aeetone/distilled water series. Speeimens were eritieal point dried in liquid CO 2 , mounted
on stubs, gold-plated under vaeuum to a thiekness of 200 A in an Agar High Resolution Sputter Coater
Model 20, and examined in a Hitaehi S-4300 SEM at an aeeelerating voltage of 5 kV.
Speeimens from New Zealand were eolleeted by Christine (Gamble) Powell in the Abel Tasman National
Park and subsequently eultured as the strain Stegelleta sp. JB-75, whieh was sequeneed and ineluded in
a phylogenetie study on Cephalobina (Nadler et al. 2006). Additional material from the Castleelifif beaeh
in New Zealand was supplied by Dieter Sturhan and Gregor Yeates. This is one of the loealities where the
original populations of S. iketaia Yeates, 1967 were eolleeted. Speeimens from Senegal were eolleeted
in the Kaolaek region, Thysse-Kaymor by Ceeile Villenave. For LM, the speeimens from New Zealand
and Senegal were proeessed using different modifieations of a slow evaporation method. Speeimens
from the strain Stegelleta sp. JB-75 were proeessed to SEM by Dan Bumbarger and photographs were
put at our disposal.
Morphometrie eharaeters applied herein and their abbreviations are as defined for Cephalobidae in
De Ley et al. (1999); terminology of the labial and eephalie region and stoma terminology follows
Holovaehov et al. (2009). Type and other speeimens are deposited in the invertebrate eolleetions of the
Department of Zoology, Swedish Museum of Natural History, Stoekholm, Sweden (SMNH).
2
BOSTROM S. & HOLOVACHOV O., Species of Stegelleta and revision of the genus
Results
Class Chromadorea Inglis, 1983
Order Rhabditida Chitwood, 1933
Family Cephalobidae Filipjev, 1934
Genus Stegelleta Thome, 1938
StegellaT\ioxx\Q, 1937: 4 [junior homonym of Stegella Stechow, 1919],
Stegelleta Thome, 1938: 64-65.
Type species
Stegella incisa Thome, 1937.
Diagnosis (emended after Holovachov et al. 2009)
Cuticle annulated, without distinctly annulated internal layer; annuli with longitudinal incisures
(tessellated). Lateral field with two or four wings (appearing as three, four or five incisures); ending
at tail terminus in females and in males. Lip region weakly offset, consisting of six globular lips
arranged in three pairs: one dorsal and two subventral. Pairs of lips separated by primary axils; guarding
processes absent; secondary axils undeveloped. Cephalic probolae absent or in the shape of one acute
tine extending along the primary axil occurring only on lateral lips or on all six lips. Labial probolae
elongate-conoid with broad basis, bifurcated about halfway forming two slender prongs, in some species
further bifurcated apically. Six labial and four cephalic papilliform sensilla arranged in a cephaloboid
manner. Amphidial aperture slit-shaped, located on lateral lips. Stoma divided into cheilo-, gymno- and
stegostom: cheilostom barrel-shaped with strongly sclerotized bacilliform cheilorhabdia; gymnostom
weakly developed, as wide as stegostom, with weak gymnorhabdia; stegostom consists of a funnel-shaped
prostegostom and variably shaped mesostego-, metastego- and telostegostom parts. Metastegostom
denticle present. Pharynx cephaloboid: pharyngeal procorpus and metacorpus cylindrical, lining of
procorpus and metacorpus are of same thickness; isthmus narrower than metacorpus; basal pharyngeal
bulb oval, with strongly developed valves. Nerve ring encircling posterior part of metacorpus or anterior
part of isthmus. Excretory pore opens at level of nerve ring, at posterior part of metacorpus or anterior
part of isthmus. Deirids present. Female reproductive system cephaloboid; posterior part of ovary
straight; spermatheca present; postvulval uterine sac present; vagina straight; vulva flat, vulval flap
absent or present. Male reproductive system cephaloboid; spicules cephaloboid with manubrium and
corpus of approximately equal width; gubemaculum plate-like or wedge-shaped; cornua crurum present.
Male genital papillae: at least one ventrosublateral pair located anterior to cloaca; one ventrosublateral
pair located at the level of cloacal opening; two pairs located at middle of tail length; and three pairs
(lateral, subventral and subdorsal) near tail terminus; there is a midventral papilla on anterior cloacal lip.
Rectum short (1-2 times longer than anal body diameter). Phasmids located at about one-third to half of
tail length in both sexes. Female tail conoid or subcylindrical, straight, tail terminus bluntly rounded or
truncate; male tail conoid, arcuate ventrad, tail terminus bluntly rounded.
Valid species
Stegelleta arenaria Bostrom & Holovachov, 2012
Stegelleta georgica Bagaturija, 1973
Stegelleta iketaia Yeates, 1967
Stegelleta incisa (Thome, 1937)
Stegelleta ophioglossa An&rassy, 1967
= Stegelleta cylindricaMsi\\]ano\, 1978: 1889, figs 1-6
Stegelleta tuarua Yeates, 1967
3
European Journal of Taxonomy 87 : 1-19 ( 2014 )
Stegelleta incisa (Thome, 1937)
Figs lA-E, 2, Table 1
Stegella incisa Thome, 1937: 14-15, fig. 4G-1.
Stegelleta incisa -ThomQ 1938: 65.
Stegelleta ophioglossa - Orselli & Vineiguerra 2002: 216-219, figs 5, 6A-C.
Diagnosis
Stegelleta incisa is eharaeterised by a 465-580 gm long body in females and 428-600 gm in males;
eutiele divided by regular longitudinal striations into 16 rows of bloeks at midbody (exeluding lateral
field); lateral field with four ineisures extending almost to tail terminus in females and to midtail papillae
in males, two outer ineisures extend to tail terminus in males; three pairs of asymmetrieal lips, pairs of
lips separated by U-shaped primary axils without guarding proeesses, seeondary axils demareated by
a shallow ineisure, eaeh lip asymmetrieally reetangular with a smooth margin and without tines; three
labial probolae, bifureated at half of their length, prongs bent toward one another apieally, “snake-
tongue”-shaped; pharyngeal eorpus 2.1-2.9 times isthmus length; nerve ring and exeretory pore at
level of metaeorpus to metaeorpus-isthmus junetion, deirids at level of metaeorpus-isthmus junetion to
isthmus; vulva with anterior fiap; spermatheea 24^3 pm long; postuterine sae 22-36 pm long; spieules
22-36 pm long.
Material examined
USA: 13 $$, 9 SS, SMNH 135940-135942, 28 Mar. 2010, California, Mojave National Preserve,
Kelso Dunes, soil around roots of desert plants (34°53.698’ N, 115° 42.155’ W and 34° 53.754’ N, 115°
42.248’ W), legit O. Holovaehov & P. De Ley.
Description
Adult
Body slightly areuate in different ways when killed by heat, males often strongly areuate ventrad in tail
end. Cutiele eoarsely annulated, annuli 2.4-3.4 pm wide at midbody and 2.2-3.0 pm wide in pharyngeal
region. Cutiele tessellated: longitudinal striae giving it a tiled appearanee, eaeh bloek often with a eentral
indentation as seen under SEM. Anteriorly, 9-10 first annuli, the longitudinal striation is irregular and
bloeks rounded, followed by a more regular striation ereating reetangular bloeks, 16 rows of bloeks at
midbody (exeluding lateral field). Lateral field eonsisting of two wings separated by a broad groove,
appearing as four ineisures under EM, oeeupying about 20-25% of body diameter, extending almost
to tail terminus in females and to midtail papillae in males, two outer ineisures extend to tail terminus
in males. Lip region slightly offset, earrying 6 + 4 papillae and two round amphids. Three pairs of
asymmetrieal lips, one dorsal and two ventrolateral. Pairs of lips separated by U-shaped primary axils
without guarding proeesses. Eaeh pair with a shallow ineisure demareating a seeondary axil. Eaeh lip
asymmetrieally reetangular with a smooth margin, without any tines. Three labial probolae, 8.0-9.5 pm
high, bifureated at half of their length, prongs bent toward one another apieally (“snake-tongue”-shaped).
Stoma somewhat longer than lip region diameter. Stomatal parts not elearly diseemible. Cheilorhabdia
baeilliform in lateromedian view; metastegostom with a dorsal dentiele. Pharynx eephaloboid.
Pharyngeal eorpus eylindrieal; isthmus narrow, often folded, and not elearly demareated from eorpus;
bulb oval, with valves. Nerve ring at level of metaeorpus to metaeorpus-isthmus junetion. Exeretory
pore and deirids at level of metaeorpus-isthmus junetion to isthmus.
Female
Reproduetive system monodelphie, prodelphie, in dextral position in relation to intestine. Ovary refiexed
posteriorly at oviduet, ovary straight posterior to vulva. Spermatheea well developed. Postvulval uterine
4
BOSTROM S. & HOLOVACHOV O., Species of Stegelleta and revision of the genus
Fig. 1. A-E. Stegelleta incisa (Thome, 1937). A. Pharyngeal region. B. Female gonad. C. Anterior end,
surface view. D. Female tail. E. Male tail. E-J. Stegelleta laterocornuta sp. nov. E. Pharyngeal region.
G. Female gonad. H. Anterior end, surface view. I. Female tail. J. Male tail. Scale bar = 20 pm.
5
European Journal of Taxonomy 87: 1-19 (2014)
sac one to one-and-a-half times vulval body diameter long. Vagina about one-third of vulval body
diameter. Vulval lips not or slightly protruding, anterior lip with eutieular flap direeted posteriad and
partly eovering vulval opening. Vulva eovered by genital plug in some speeimens. Tail eonoid with
13-15 ventral annuli, terminus truneate. One speeimen has a tail with only 10-11 annuli and broadly
rounded terminus. Phasmids loeated at about one-third to half of tail length.
Male
Reproduetive system monorehie, dextral in position; testis reflexed ventrad anteriorly. Spieules paired
and symmetrieal, eurved ventrad; with oval manubrium and subeylindrieal, gradually narrowing shaft.
Gubemaeulum plate-like, eomua erurum present. Tail strongly areuate ventrad, eonoid with rounded
terminus. The two outer lateral lines extend posterior to the phasmid, transforming into a eutieular
ridge that reaehes tail terminus. Genital papillae arranged as follows: two pairs sub ventral preeloaeal (at
24-33 pm and at 42-58 pm anterior to eloaea), one pair subventral adeloaeal, a single midventral papilla
Fig. 2. Stegelleta incisa (Thome, 1937), SEM mierographs. A-B. Anterior end, left lateral view. C. Anterior
part of lateral fleld. D. Deirid (arrow). E. Vulval region. F. Female tail, subventral view. G. Female tail,
left sublateral view (arrow points at phasmid). H. Female tail, lateral view. Seale bars = 5 pm.
6
BOSTROM S. & HOLOVACHOV O., Species of Stegelleta and revision of the genus
Table 1. Measurements (in pm) of Stegelleta incisa (Thome, 1937) from Kelso Dunes, California compared
with the type population of S. incisa from Utah and a bisexual population described by Orselli & Vinciguerra
(2002) from Italy under the name S. ophioglossa Axi&xkssy, 1967 (presented as mean ± s.d. and (range) or
only range). * Calculated from data in original publication; ** number of annuli from anterior end to nerve
ring, excretory pore and deirid, respectively; ci estimated from drawings in original publication; - indicates
that data is not available or not applicable; figures within [ ] indicate the number of specimens measured.
Population
Utah
Kelso Dunes, California
Italy
No. & sex
1$
10$$
11 (?<?
5$$
St?.?
Body length
500
460
490 ± 23
(465-534)
463 ± 28
(428-526)
550 ± 30
(510-580)
550 ± 30
(510-600)
Body diameter (BD)
24*
20*
23.2 ± 1.0
(22-25)
21.2± 1.7
(18-24)
29 ± 1.4
(27.5-30.8)
25.3 ±2.6
(20.9-27.5)
Pharynx length
139*
115*
130.6± 1.0
(115-141)
123.9 ±7.9
(107-135)
181.4±6.1
(177-192)
184.8 ±24.2
(161-225)
Tail length
34*
34*
38.8 ± 1.7
(32M1)
32.2 ±2.5
(29-36)
50.1 ±3.6
(44-53.9)
48.6 ±3.6
(45.1-53.9)
Anal or cloacal diam. (ABD)
-
-
14.4 ±0.2
(14.0-14.5)
16.1 ± 1.0
(14.5-18.0)
18.4 ±0.4
(17.6-18.7)
22± 1.1
(20.9-23.1)
Vulva or Testis
-
-
307 ± 14
(291-335)
269 ± 23
(223-300)
-
-
V-A/T
-
-
3.8 ±0.2
(3.4M.1)
-
-
-
a
21
23
21.2 ±0.9
(19.6-22.5)
21.9± 1.3
(19.5-24.2)
19±2
(17-21)
22 ± 2.2
(15-25)
b
3.6
4
3.8 ±0.2
(3.5M.2)
3.7 ±0.2
(3.4M.3)
3 ±0.1
(2.8-3.2)
2.9 ±0.2
(2.6-3.3)
c
15.0
13.5
12.7 ±0.6
(11.8-13.4)
14.4 ± 1.0
(12.7-15.5)
11 ±0.5
(10.4-11.5)
11.3±0.6
(10.9-12.2)
c’
-
-
2.7 ±0.1
(2.5-2.8)
2.0 ±0.2
(1.8-2.3)
2.6 ±0.2
(2.3-2.9)
2.1 ±0.1
(1.9-2.3)
VorT(%)
66
41
62.7 ± 1.1
(61-65)
58.1 ±3.4
(52-64)
62.5 ±0.6
(61.4-63)
-
Lip region diameter
-
-
8.3 ±0.3
(7.5-8.5)
8.0 ±0.6
(7.0-8.5)
-
-
Stoma length
-
-
9.8 ±0.9
(8.5-11.0)
9.7 ±0.6
(9-11)
13.2 ±2
(11-15.4)
13.5 ±0.4
(13.2-14.3)
Corpus length
-
-
83.2 ±2.8
(78-86) [5]
81.2±3.9
(76-87) [5]
123 ±5.4
(117-129)
123.6 ±21.5
(102-159)
Isthmus length
-
-
34.2 ±2.7
(29-36) [5]
31.8±2.4
(30-36) [5]
30.3 ±7.5
(17.6-36.3)
32.7 ±4.6
(25.3-37.4)
Bulb length
-
-
16.6 ±0.7
(16-18)
15.7 ±0.9
(14.5-17.0) [6]
20.2 ±2.1
(17.6-23.1)
18.8 ±0.6
(18.1-19.8)
Bulb diameter
-
-
12.2 ±0.7
(11-13)
11.8±0.7
(11-13) [6]
-
-
Corpus/isthmus ratio
3
-
2.4 ±0.2
(23-2.9) [5]
2.6 ±0.2
(2.1-2.8) [5]
-
-
Nerve ring from ant. end
-
-
88.5 ±4.5
(78-94)
90.2 ±7.1
(78-102)
137.5 ±6.3
(129-144)
141.8±23.1
(118-179)
7
European Journal of Taxonomy 87: 1-19 (2014)
Population
Utah
Kelso Dunes, California
Italy
No. & sex
1$
10
11 (?<?
5?9
Excretory pore from ant. end
-
-
93.8 ±2.9
(88-99)
95.6 ±7.0
(84-108)
122-147
-
Deirid from ant. end
-
-
101.1 ±3.4
(94-107)
101.5 ±8.3
(82-114)
-
-
u **
^NR
-
-
32 ± 1.5
(30-35)
32 ±2
(30-36)
-
-
u **
^EP
-
-
34 ±2
(32-38)
34 ±2
(31-38)
-
-
TJ **
DEI
-
-
37 ±2
(35M1)
37 ±2
(34M1)
-
-
Annuli width at midbody
-
-
2.4-3.4
2.4-3.0
2.0-2.5
-
Annuli width anteriorly
-
-
2.4-2.7
2.2-3.0
-
-
Vagina or Testis flexure length
-
-
7.3 ±0.4
(7-8)
39.5 ±6.7
(27M8)
7-8
-
Spermatheca or Spicule length
-
-
30.9 ±6.7
(24M3)
24.0 ± 1.3
(22-27)
24-26.5
34.5 ± 1.6
(31.9-36.3)
PUS or Gubernaculum length
-
-
27.3 ±2.3
(24-31)
13.2± 1.1
(12-16)
30.6 ±5.9
(22.5-36.3)
20.4 ± 1.4
(19.8-23.1)
PUSA^BD
-
-
1.3±0.1
(1.1-1.4)
-
0.7-1.3
-
Rectum
-
-
16.0± 1.6
(13-18)
-
21.6 ±0.3
(16.5-24.7)
-
Rectum/ABD
-
-
1.1 ±0.1
(0.9-1.2)
-
-
-
Phasmid
-
-
14.9 ±2.2
(12-20)
14.1 ± 1.8
(11-18)
-
-
Phasmid (% of tail)
30 a
47 a
38.3 ±4.6
(32M9)
43.8 ±4.7
(37-50)
15-30
25-35
on anterior cloacal lip; two pairs (one ventrosublateral and one lateral) at midtail; three pairs (one lateral,
one subventral and one dorsosublateral) eloser to tail terminus. Phasmids loeated at about two-fifths to
half of tail length.
Remarks
The population eolleeted from sand in the Kelso Dunes area, Mojave Desert, California and deseribed
here, agrees in many respeets with the type speeimens of Stegelleta incisa deseribed from Utah by
Thome (1937) and a bisexual population deseribed from Italy by Orselli & Vineiguerra (2002) under
the name S. ophioglossa. One major differenee is the presenee of a eutieular fiap on the anterior vulval
lip direeted posteriad and partly eovering the vulval opening, as seen by SEM in the present speeimens.
This feature is not easily seen with light mieroseopy, whieh probably explains why it was not mentioned
by Thome (1937) in his original deseription. Orselli & Vineiguerra (2002) also did not mention or
illustrate it in their speeimens, presumably for the same reason.
8
BOSTROM S. & HOLOVACHOV O., Species of Stegelleta and revision of the genus
Stegelleta laterocornuta sp. nov.
um:lsid:zoobank.org:act:7669B17A-D71A-46C0-8BAQ-EB92F28B7111
Figs IF-J, 3, Table 2
Stegelleta sp. JB-75 -Nadler et al. 2006: 701, table 1.
Diagnosis
Stegelleta laterocornuta sp. nov. is characterised by a 379-512 pm long body in females and 365^76 pm
in males; cuticle divided by regular longitudinal striations into 16 rows of blocks at midbody (excluding
lateral field); lateral field with four incisures extending almost to tail terminus in females and to midtail
papillae in males, two outer incisures extend to tail terminus in males; three pairs of asymmetrical
lips, pairs of lips separated by U-shaped primary axils without guarding processes, secondary axils
demarcated by a shallow incisure, each lip asymmetrically rectangular with a smooth margin, only
lateral lips have slender acute tines; three labial probolae, bifurcated at half of their length, prongs bent
toward one another apically, “snake-tongue”-shaped; pharyngeal corpus 2.3-3.0 times isthmus length;
nerve ring and excretory pore at level of metacorpus to metacorpus-isthmus junction, deirids at level
of isthmus; vulva without fiap; spermatheca 17-31 pm long; postuterine sac 7-24 pm long; spicules
21.5-23.5 pm long.
Etymology
The species name is derived from the Fatin lateris (= side) and cornu (= horn), referring to the long acute
tine extending along the primary axil on the lateral lips.
Material examined
NFW ZEAFAND: holotype $, paratypes 13 $$ and 9 SS, SMNH Type-8602, 1999, South Island,
Tasman District, Abel Tasman National Park, legit Christine (Gamble) Powell, cultured as the strain
Stegelleta sp. JB-75.
Description
Adult
Body slightly arcuate in different ways when killed by heat, males often strongly arcuate ventrad in tail
end. Cuticle coarsely annulated, annuli 1.9-2.7 pm wide at midbody and 2.0-2.4 pm wide in pharyngeal
region. Cuticle tessellated: longitudinal striae giving it a tiled appearance, 16 rows of blocks at midbody
(excluding lateral field). Fateral field consisting of two wings separated by a broad groove, appearing as
four incisures under FM, occupying about 20-25% of body diameter, extending almost to tail terminus
in females and in males. Fip region slightly offset, carrying 6 + 4 papillae and two round amphids. Three
pairs of asymmetrical lips, one dorsal and two ventrolateral. Pairs of lips separated by U-shaped primary
axils without guarding processes. Each pair with a shallow incisure demarcating a secondary axil. Each
lip asymmetrically rectangular with a smooth margin. Fateral lips only with long, slender, acute tine
extending along the primary axil. Three labial probolae, 7.0-8.5 pm high, bifurcated at half of their
length, prongs bent toward one another apically (“snake-tongue”-shaped). Stoma somewhat longer than
lip region diameter. Stomatal parts not clearly discernible. Cheilorhabdia bacilliform in lateromedian
view; metastegostom with a dorsal denticle. Pharynx cephaloboid. Pharyngeal corpus cylindrical; isthmus
narrow, often wrinkled, and not clearly demarcated from corpus; bulb oval, with valves. Nerve ring and
excretory pore at level of metacorpus-isthmus junction to isthmus. Deirids generally at level of isthmus.
Female
Reproductive system monodelphic, prodelphic, in dextral position in relation to intestine. Ovary refiexed
posteriorly at oviduct, ovary straight posterior to vulva. Spermatheca well developed. Postvulval uterine
9
European Journal of Taxonomy 87: 1-19 (2014)
sac about half to one-and-a-half times vulval body diameter long. Vagina about one-third of vulval
body diameter. Vulval lips not or slightly protruding, without flaps. Vulva with genital plug seen in one
speeimen. In four females one intrauterine egg eaeh was found, measuring 36-57 x 14.5-15.5 pm. Tail
eonoid with 16-22 ventral annuli, terminus broadly rounded or truneate. Phasmids loeated at about one-
third to two-flfths of tail length.
Male
Reproduetive system monorehie, dextral in position; testis reflexed ventrad anteriorly. Spieules paired
and symmetrieal, eurved ventrad; with oval manubrium and subeylindrieal, gradually narrowing shaft.
Gubemaeulum plate-like, eomua erurum present. Tail strongly areuate ventrad, eonoid with rounded
terminus. The two outer lateral lines extend posterior to the phasmid, transforming into a eutieular
ridge that reaehes tail terminus. Genital papillae arranged as follows: two pairs sub ventral preeloaeal (at
4-6 pm and at 23-28 pm anterior to eloaea), one pair subventral adeloaeal, a single midventral papilla
on anterior eloaeal lip; two pairs (one ventrosublateral and one lateral) at midtail; three pairs (one lateral,
one subventral and one dorsosublateral) eloser to tail terminus. Phasmids loeated at about two-flfths to
half of tail length.
Remarks
The population of Stegelleta laterocornuta sp. nov. Ifom New Zealand deseribed here agrees in many
respeets with the deseriptions of S. incisa. One major differenee is the presenee of a long, slender and
Fig. 3. Stegelleta laterocornuta sp. nov., SEM mierographs. A. Vulval opening. B. Anal opening.
C-D. Anterior end, left subventral view. E. Anterior end, left lateral view (arrows in C-E point at the
long aeute tine extending along the primary axil on the lateral lips). Seale bars = 2 pm.
10
BOSTROM S. & HOLOVACHOV O., Species of Stegelleta and revision of the genus
Table 2. Measurements (in pm) of Stegelleta laterocornuta sp. nov. and S. tuarua Yeates, 1967 from
Castleclifif, New Zealand, the latter compared to the type population (presented as mean ± s.d. and
(range) or only range).* Number of annuli from anterior end to nerve ring, excretory pore and deirid,
respectively; - indicates that data is not available or not applicable.
Stegelleta laterocornuta sp. nov.
Stegelleta tuarua
Population
New Zealand JB-75
Type population
Castlecliff
No. & sex
Holotype
14 5 5 (incl.
holotype)
9 SS {1 aberr.}
1?
Body length
447
433 ±41
(379-512)
428 ± 35
(365M76)
635
563-739
650; 688
Body diameter (BD)
20.5
19.1 ± 1.7
(15.5-21.5)
17.4± 1.1
(15-19)
-
-
45; 46
Pharynx length
118
116.7 ±5.2
(109-126)
117.8±4.6
(109-123){138}
-
-
144; 165
Tail length
38
35.9 ±2.9
(30M2)
24.2 ±0.9
(22-25){36}
-
-
43; 48
Anal or cloacal diam.
(ABD)
11
11.1 ±0.8
(9.5-12.5)
11.9±0.4
(11.0-12.5) {13}
-
-
30; 30
Vulva or Testis
273
270 ± 22
(235-315)
223 ± 15
(200-235)
-
-
432; 476
V-A/T
3.6
3.6 ±0.3
(3.0-3.9)
-
-
-
-
a
21.8
22.7 ± 1.7
(18.6-26.0)
24.6 ± 1.3
(21.5-26.5)
21.2
17.2-18.8
14.4; 15.0
b
3.8
3.7 ±0.3
(3.4M.3)
3.6 ±0.2
(3.3M.0)
3.8
3.9-4.8
4.5; 4.2
c
11.8
12.1 ±0.7
(10.5-13.0)
17.7 ± 1.4
(15.2-19.8) {13.1}
25.4
14.1-16.0
15.1; 14.3
c’
3.5
3.2 ±0.2
(2.7-3.6)
2.0 ±0.1
(1.8-2.2) {2.8}
1.6
1.6-1.9
1.4; 1.6
V or T (%)
61
62.3 ± 1.2
(60-65)
54.2 ±3.7
(49-60)
69.2
56.8-62.7
66; 69
Lip region diameter
7.0
6.8 ±0.4
(6.5-8.0)
6.7 ±0.4
(6-7)
-
-
11; 12
Stoma length
9.0
8.9 ±0.3
(8.5-9.5)
8.7 ±0.5
(8.0-9.5)
-
-
14.5; 19
Corpus length
70
69.6 ±4.1
(63-75)
69.6 ± 1.9
(66-72){81}
-
-
92; 110
Isthmus length
26
26.7 ±2.3
(24-30)
27.1 ± 1.7
(24-29){36}
-
-
22; 20.5
Bulb length
14.5
14.8 ± 1.0
(13-17)
14.3 ±0.7
(13.0-15.5) {17}
-
-
23; 24
Bulb diameter
11
11.5±0.7
(10-13)
11.0±0.7
(10-12)
-
-
19; 20.5
Corpus/isthmus ratio
2.7
2.6 ±0.2
(2.3-3.0)
2.6 ±0.2
(2.4-2.9) {2.3}
-
-
4.2; 5.4
Nerve ring from ant. end
92
83.0 ±7.7
(70-96)
86.6 ±6.4
(77-96){102}
-
-
108; 121
11
European Journal of Taxonomy 87: 1-19 (2014)
Stegelleta laterocornuta sp. nov.
Stegelleta tuarua
Population
New Zealand JB-75
Type population
Castlecliff
No. & sex
Holotype
14 5 5 (incl.
holotype)
9 SS {1 aberr.}
1?
^33
2 33
Excretory pore from ant.
end
94
86.3 ±8.1
(72-97)
92.0 ±6.6
(81-99){106}
-
-
?; 130
Deirid from ant. end
100
92.9 ±7.2
(81-104)
100.2 ±5.6
(89-105){107}
-
-
141; 171
n *
^NR
42
35 ±4
(28^2)
35 ±2
(32-39){47}
-
-
35; 38
n *
^EP
43
37 ±4
(32^3)
37 ±2
(33-39){49}
-
-
?;41
R *
DEI
46
40 ±4
(35^8)
42 ±2
(37^4) {50}
-
-
46; 55
Annuli width at midbody
2.7
2.0-21
2.0-2.7
-
-
2.4; 2.4
Annuli width anteriorly
2.0
2.0-2.4
2.0-2.4
-
-
3.0-3.4; 3.0-3.4
Vagina or Testis flexure
length
6.0
6.0 ±0.6
(5-7)
39.8 ±3.9
(35^6)
-
-
90 (dors); 82
Spermatheca or Spicule
length
18
20.6 ±4.6
(17-31)
22.5 ±0.7
(21.5-23.5)
-
36-40
43; 42
PUS or Gubernaculum
length
17
18.1 ±5.9
(7-24)
11.4±0.5
(11-12)
-
21-24
25; 24
PUSA^BD
0.9
1.0 ±0.3
(0.6-1.3)
-
-
-
-
Rectum
17
16.6± 1.1
(15.5-19.0)
-
-
-
-
Rectum/ABD
1.5
1.5±0.1
(1.4-1.6)
-
-
-
-
Phasmid
12
11.6±0.7
(10-13)
10.6± 1.1
(8.5-12.0) {18}
-
-
18; 18
Phasmid (% of tail)
32
32.2 ± 1.7
(30-37)
44.0 ±3.6
(38-50)
-
~40
42; 38
acute tine extending along the primary axil on the lateral lips. This is a somewhat intermediate stage
between S. incisa, whieh has no tines, and S. arenaria, in whieh eaeh lip has one aeute tine extending
along the primary axil. Another differenee is the absenee of a eutieular flap on the anterior vulval lip, as
seen by SEM in the speeimens of S. incisa from California.
Stegelleta ophioglossa Andrassy, 1967
Fig. 4A-D, Table 3
Stegelleta ophioglossa Andrassy, 1967: 208-210, flg. 3.
Diagnosis
Stegelleta ophioglossa is eharaeterised by a 315^90 pm long body in females; eutiele divided by regular
longitudinal striations into 12-16 rows of bloeks at midbody (exeluding lateral held); lateral held with
four ineisures extending almost to tail terminus in females; three pairs of asymmetrieal lips, pairs of
lips separated by U-shaped primary axils without guarding proeesses, seeondary axils demareated by
12
BOSTROM S. & HOLOVACHOV O., Species of Stegelleta and revision of the genus
a shallow incisure, each lip asymmetrically rectangular with a smooth margin and without tines; three
labial probolae, bifurcated at half of their length, prongs bent toward one another apically, “snake-
tongue”-shaped; pharyngeal corpus 3-5 times isthmus length; nerve ring, excretory pore and deirids at
level of isthmus; vulva without flap; spermatheca 7-13 pm long; postuterine sac 7-17 pm long.
Fig. 4. A-D. Stegelleta ophioglossa Andrassy, 1967. A. Pharyngeal region. B. Anterior end, surface
view. C. Female gonad. D. Female tail. E-G. Stegelleta tuarua Yeates, 1967. E. Pharyngeal region.
E. Anterior end, surface view. G. Male tail. Scale bar = 20 pm.
13
European Journal of Taxonomy 87: 1-19 (2014)
Table 3. Measurements of females of Stegelleta ophioglossa Andrassy, 1967 from Senegal eompared
with other populations of the same speeies (presented as mean ± s.d. and (range) or only range).
* Caleulated from data in original publieation. ** Number of annuli from anterior end to nerve ring,
exeretory pore and deirid, respeetively; - indieates that data is not available or not applieable.
Population
Mongolia
Uzbekistan
Senegal
Iran
Spain
Senegal
Reference
Andrassy
1967
Mavljanov
1978
De Ley et al.
1990
Shokoohi
et al. 2008
Abolafia
et al. 2011
This paper
No. & sex
19 9 $
899
499
?99
699
Body length
470M90
335-390
347 ± 16
(324-356)
347 ± 17.5
(324-356)
330-420
353 ± 22
(315-382)
Body diameter (BD)
-
17.7*
15-18
16.1 ± 1.2
(15-18)
-
17.9± 1.5
(15.5-20.5)
Pharynx length
-
114.7*
104 ±5
(99-111)
93.9 ±3.2
(90-98)
-
102.7 ±3.8
(97-107)
Tail length
-
34.8*
31 ±2
(28-33)
30.0 ± 1.5
(29-32)
27-32
31.6± 1.8
(29-34)
Anal body diam. (ABD)
-
10
9-10
9.6 ±0.7
(9-10)
-
10.8 ±0.6
(9.5-11.5)
Vulva
-
253*
-
219.7 ± 12.6
(209-238)
-
224 ± 13
(200-243)
V-A/T
-
-
-
-
-
3.1 ±0.1
(2.8-3.2)
a
20-21
18.1-22.9
21.3 ± 1.2
(19.7-23.1)
21.6 ±0.6
(20.8-21.9)
19-23
19.8 ±0.8
(18.6-20.4)
b
3.3-3.4
3.1-3.6
3.3 ±0.1
(3.2-3.5)
3.7 ±0.1
(3.7-3.8)
3.2-3.6
3.4 ±0.2
(3.2-3.7)
c
11-12
10.4-11.8
11.2±0.6
(10.4-12.9)
11.6±0.2
(11.3-11.8)
12-13
11.2±0.4
(10.5-11.6)
c’
3.0-3.5
3.3 ±0.2
(3.0-3.6)
3.1 ±0.3
(2.9-3.4)
2.3-2.7
2.9 ±0.2
(2.6-3.2)
V (%)
60-62
63.0-66.8
61-63
63.2 ±0.6
(63-64)
62-63
63.5 ±0.8
(63-65)
Lip region diameter
-
-
-
4.9 ±0.7
(4-6)
-
6.6 ±0.3
(6-7)
Stoma length
-
-
7-9
7.8 ± 1.2
(6-8)
-
8.8 ±0.3
(8.5-9.0)
Corpus length
-
-
67 ±3
(63-71)
63.5 ±3.6
(60-68)
-
65.9 ±2.9
(61.5-69.0)
Isthmus length
-
-
22 ±2
(18-25)
14.7 ±2.8
(12-18)
-
15.9± 1.1
(14.5-17.0)
Bulb length
-
-
13-14
16.0 ±0.9
(16-17)
-
14.1 ±0.9
(12.0-14.5)
Bulb diameter
-
-
-
-
-
11.3±0.9
(9.5-12.0)
Corpus/isthmus ratio
-
-
3
3.8-5.0
3
4.2 ±0.2
(4.0M.4)
Nerve ring from ant. end
-
-
68 ±4
(60-71)
67.7 ±2.9
(64-71)
-
76 ±3.6
(69-81)
14
BOSTROM S. & HOLOVACHOV O., Species of Stegelleta and revision of the genus
Population
Mongolia
Uzbekistan
Senegal
Iran
Spain
Senegal
Excr. pore from ant. end
-
-
66 + 3
(61-71)
69.4 + 3.6
(70-74)
-
79.5 + 3.5
(72-83)
Deirid from ant. end
-
-
75 + 2
(72-78)
73.6 + 3.3
(70-78)
-
82.3 + 4.0
(75-87)
u **
^NR
-
-
-
-
-
36+1
(35-37)
u **
^EP
-
-
-
36-39
-
37+1
(36-38)
TJ **
DEI
-
-
-
43
-
39+1
(37^0)
Annuli width at midbody
1.7-2.0
2.1
1.5-2.1
1.7-2.3
-
1.6-2.2
Annuli width anteriorly
-
1.5
-
-
-
1.7-2.0
Vagina length
-
-
3-5
6.2+ 0.6
(6-7)
-
5.8+ 0.3
(5.5-6.0)
Spermatheca length
-
-
< 13
8.1 (n=l)
13
8.9+ 1.7
(7-12)
PUS length
-
-
11-14
13.6 + 4.9
(8-17)
10
7.0-8.5
PUSA^BD
~1
-
1.1-1.4
0.5-0.9
-
0.4-0.5
Rectum
-
-
13 + 2
(10-16)
12.7 + 0.8
(12-14)
-
12.7+1.5
(9.5-14.5)
Rectum/ABD
1.7-2.0
-
-
1.3-1.4
> 1
1.2 + 0.1
(1.0-1.3)
Phasmid
-
-
-
-
-
8.8+ 0.4
(8.5-9.5)
Phasmid (% of tail)
~30
-
21-29
24-31
33-46
27.5 + 2.4
(25-32)
Rows of cuticle blocks
14
16
16
-
12
16
Material examined
SENEGAL: 6 SMNH 135943-135944, Kaolack region, Thysse-Kaymor, legit C. Villenave.
Description
Adult
Body slightly arcuate ventrad when killed by heat. Cuticle annulated, annuli 1.6-2.2 pm wide at
midbody and 1.7-2.0 pm wide in pharyngeal region. Cuticle tessellated: longitudinal striae giving it a
tiled appearance, 16 rows of blocks at midbody (excluding lateral field). Lateral field consisting of two
wings separated by a narrow groove, appearing as four incisures under EM, occupying about 20% of
body diameter, extending almost to tail terminus in females. Lip region slightly offset, carrying 6 + 4
papillae and two round amphids. Three pairs of asymmetrical lips, one dorsal and two ventrolateral.
Pairs of lips separated by U-shaped primary axils without guarding processes. Each pair with a shallow
incisure demarcating a secondary axil. Each lip asymmetrically rectangular with a smooth margin. Three
labial probolae, 6-7 pm high, bifurcated at half of their length, prongs bent toward one another apically
(“snake-tongue”-shaped). Stoma somewhat longer than lip region diameter. Stomatal parts not clearly
discernible. Cheilorhabdia bacilliform in lateromedian view; metastegostom with a dorsal denticle.
Pharynx cephaloboid. Pharyngeal corpus cylindrical; isthmus narrow, not clearly demarcated from
corpus; bulb oval, with valves. Nerve ring, excretory pore and deirids at level of isthmus.
15
European Journal of Taxonomy 87: 1-19 (2014)
Female
Reproductive system monodelphic, prodelphic, in dextral position in relation to intestine. Ovary reflexed
posteriorly at oviduct, ovary straight posterior to vulva. Spermatheca small, not developed. Postvulval
uterine sac short, about one-half of vulval body diameter long. Vagina about one-third of vulval body
diameter. Vulval lips not protruding. Tail conoid with 12-20 ventral annuli, terminus truncate. Phasmids
located at about one-fourth to one-third of tail length.
Male
Not found.
Remarks
The specimens described here agree in many respects with the population of Stegelleta ophioglossa from
Senegal described by De Ley et al. (1990) and several other populations of S. ophioglossa (Andrassy
1967; Mavljanov 1978; Shokoohi et al. 2008; Abolafla et al. 2011).
Stegelleta tuarua Yeates, 1967
Fig. 4E-G, Table 2
Stegelleta tuarua YQSLtQS, 1967: 536-538, flg. 5.
Diagnosis
Stegelleta tuarua is characterised by a 635 pm long body in females and 563-739 pm in males; cuticle
divided by regular longitudinal striations into 40^4 rows of blocks at midbody; lateral held with flve
incisures extending almost to tail terminus in females and in males; three pairs of asymmetrical lips, pairs
of lips separated by U-shaped primary axils without guarding processes, secondary axils demarcated
by a shallow incisure, each lip asymmetrically rectangular with a smooth margin and one tine; three
labial probolae, bifurcated at about 1/5 of their length; pharyngeal corpus 4.2-5.4 times isthmus length;
nerve ring and excretory pore at level of isthmus and deirids at level of bulb; vulva and spermatheca
undescribed, postuterine sac about 1 vulval body diameter long; spicules 21-25 pm long.
Material examined
NEW ZEAEAND: 2 SS, SMNH 135945-135946, 18 May 2008, North Island, Wanganui, Castlecliff
beach, partly stabilized coastal sand dunes with Ammophila arenaria, 50 cm deep, legit G. Yeates.
Description
Adult
Body slightly arcuate ventrad when killed by heat. Cuticle annulated, annuli 2.4 pm wide at midbody and
3.0-3.4 pm wide in pharyngeal region. Cuticle tessellated: longitudinal striae giving it a tiled appearance,
tiles are not equal in size and are not arranged in straight rows, approximately 40^4 rows of blocks at
midbody. Eateral held with flve incisures occupying about 20% of body diameter, extending almost to
tail terminus in females. Eip region slightly offset, carrying 6 + 4 papillae and two round amphids. Three
pairs of asymmetrical lips, one dorsal and two ventrolateral. Pairs of lips separated by U-shaped primary
axils without guarding processes. Each pair with a shallow incisure demarcating a secondary axil. Each
lip asymmetrically rectangular with a smooth margin and one acute tine extending along the primary
axil. Three labial probolae, 7.0-8.5 pm high, bifurcated at about 1/5 of their length. Stoma somewhat
longer than lip region diameter. Stomatal parts not clearly discernible. Cheilorhabdia bacilliform in
lateromedian view; metastegostom with a dorsal denticle. Pharynx cephaloboid. Pharyngeal corpus
cylindrical; isthmus narrow, not clearly demarcated from corpus; bulb oval, with valves. Nerve ring and
excretory pore at level of isthmus and deirids at level of bulb.
16
BOSTROM S. & HOLOVACHOV O., Species of Stegelleta and revision of the genus
Male
Reproductive system monorchic, dextral in position; testis reflexed ventrad anteriorly. Spicules paired
and symmetrical, curved ventrad; with oval manubrium and subcylindrical, gradually narrowing shaft.
Gubemaculum wedge-shaped, cornua crurum present. Tail strongly arcuate ventrad, conoid with
rounded terminus. The two outer lateral lines extend posterior to the subdorsal papilla close to tail
terminus, transforming into a cuticular ridge that reaches tail terminus. Genital papillae arranged as
follows: two pairs subventral precloacal (at 36 pm and at 74 pm anterior to cloaca), one pair subventral
adcloacal, a single midventral papilla on anterior cloacal lip; two pairs (one ventrosublateral and one
lateral) at midtail; three pairs (one lateral, one subventral and one dorsosublateral) closer to tail terminus.
Phasmids located at about two-flfths to half of tail length.
Female
Not found in our study.
Remarks
The specimens described here agree well in main morphological and morphometric features with the
original description by Yeates (1967) of the males of S. tuarua from New Zealand.
Key to species
1. Lateral fleld with flve incisures; cuticle with over 40 longitudinal rows of blocks; labial probolae
biacute apically . S. tuarua Yeates, 1967
- Lateral fleld with three-four incisures; cuticle with 12-26 longitudinal rows of blocks; labial probolae
bifurcate half of length.2
2. Labial probolae with minute secondary bifurcations at tips. S. iketaia Yeates, 1967
- Labial probolae without minute secondary bifurcations at tips.3
3. Cephalic probolae in shape of acute tines present on all six lips along the primary axils; cuticle with
24-26 longitudinal rows of blocks. S. arenaria Bostrom & Holovachov, 2012
- Cephalic probolae absent, or present only on lateral lips along the primary axils; cuticle with 12-22
longitudinal rows of blocks.4
4. Cuticle with 22 longitudinal rows of blocks. S. georgica Bagaturija, 1973
- Cuticle with 12-16 longitudinal rows of blocks.5
5. Parthenogenetic species; spermatheca 7-13 pm long; postuterine sac about 7-17 pm long.
. S. ophioglossa An&xkssy, 1967
- Amphimictic species; spermatheca 24^3 pm long; postuterine sac about 22-36 pm long.6
6. Cephalic probolae absent. S. incisa (Thome, 1937)
- Cephalic probolae setose, present on lateral lips only. S. laterocornuta sp. nov.
Discussion
Representatives of the family Cephalobidae Filipjev, 1934 are mostly terrestrial and bacteria-consuming
nematodes with a worldwide distribution, including Antarctica. They occur in tropical and temperate
regions as well as in hot and cold arid areas globally. They seem to be especially diverse and abundant
in deserts and many species have been described from warm and dry habitats like the Namib Desert in
southern Africa (see, e.g., Rashid & Heyns 1990a, b; Rashid et al. 1990a, b) and the Mojave Desert in
southern California (see, e.g., De Ley et al. 1999; Taylor et al. 2004; Waceke et al. 2005). Sand dunes
17
European Journal of Taxonomy 87: 1-19 (2014)
appear to be another suitable habitat for eephalobids, as evideneedby several studies (see, e.g., Bostrom &
Holovaehov 2012, 2013a, b; Bussau 1991; Orselli & Vineiguerra 2002; Yeates 1967). Speeies of the
genus Stegelleta are rather rare inhabitants of terrestrial habitats, although they oeeur on all eontinents
exeept Antaretiea. In the present study, a new speeies of Stegelleta, S. laterocornuta sp. nov., is deseribed
from New Zealand, whieh brings the total number of speeies in this genus to seven. Deseriptions of new
material of some already known speeies from dry areas in California and Senegal are also ineluded. This
leads to an addition of morphologieal data whieh broadens the diagnosis of Stegelleta and inereases the
number of eharaeter eombinations useful for speeies identifieation in the genus.
Acknowledgements
The seeond author was supported in part by an award from the NSF Partnerships for Enhaneing Expertise
in Taxonomy (PEET) program grant “PEET: Training the Next Generation of Nematode Taxonomists:
Applying the Tools of Modem Monography Aeross Free-living and Parasitie Tylenehina”(E)EB-0731516).
Sampling in the Mojave Desert was performed by O. Holovaehov and P. De Eey under the permit # MOJA-
2010-SC1-0003 from the National Park Serviee, United States Department of Interior. We thank D. Sturhan,
G. Yeates and C. Villenave for providing us with samples and slides, and D. Bumbarger for SEM pietures
of Stegelleta JB-75 { = S. laterocornuta sp. nov.).
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Manuscript received: 19 February 2014
Manuscript accepted: 22 April 2014
Published on: 16 June 2014
Topic editor: Rudy Jocque
Desk editor: Charlotte Thionois
Rrinted versions of all papers are also deposited in the libraries of the institutes that are members of
the EJT consortium: Museum National d’Histoire Naturelle, Raris, France; Botanic Garden Meise,
Belgium; Royal Museum for Central Africa, Tervuren, Belgium; Natural History Museum, London,
United Kingdom; Royal Belgian Institute of Natural Sciences, Bmssels, Belgium; Natural History
Museum of Denmark, Copenhagen, Denmark.
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