New Species of the Genus Pseudanthessius from Tropical Waters (Copepoda, Cyclopoida, Pseudanthessiidae)

2021·1.6 MB·

by  Jimin Lee

Anim. Syst. Evol. Divers. Vol. 37, No. 4: 287-321, October 2021
https://doi.org/10.5635/ASED.2021.37.4.031
Review article
New Species of the Genus Pseudanthessius from
Tropical Waters (Copepoda, Cyclopoida, Pseudanthessiidae)
Jimin Lee1, Il-Hoi Kim2,*
1Marine Ecosystem Research Center, Korea Institute of Ocean Science & Technology, Busan 49111, Korea
2Korea Institute of Coastal Ecology, Bucheon 14449, Korea
ABSTRACT
Nine new species of Pseudanthessius are described from tropical waters, five of which from the Philippines
(P. boholensis n. sp., P. angustus n. sp., P. firmus n. sp., P. ardius n. sp., and P. lativentris n. sp.), two from Vietnam
(P. remicaudatus n. sp. and P. nodosus n. sp.), and one each from Micronesia (P. kosraensis n. sp.) and the Thai
coast of the Andaman Sea (P. fossulicolus n. sp.). Pseudanthessius dentatus Kim, 2000 which was known originally
from the Korean coast of the Yellow Sea, and P. planus Kim, 2007 originally from the Moluccas, are rediscovered
on the Thai coast of the Andaman Sea and the Philippines, respectively.
Keywords: Copepod associates, invertebrate hosts, Micronesia, the Philippines, Vietnam, Thailand
INTRODUCTION slide method (Humes and Gooding, 1964). All figures were
drawn with the aid of a drawing attachment. Type specimens
Copepods of the family Pseudanthessiidae consist of six have been deposited in the Marine Biodiversity Institute
genera, including the most recently described Tubiporicola of Korea (MABIK), Seocheon, Korea. In the formula for
Kim, 2009, of which Pseudanthessius Claus, 1880 is the the armature of the antenna and legs 1-4, Roman numerals
largest genus currently comprising 48 valid species (WoRMS indicate spines and Arabic numerals represent setae. Ter­
Editorial Board, 2020). Species of the genus are associated minology for caudal rami and mouthparts of copepods
with various marine invertebrate hosts belonging to the follows Huys and Boxshall (1991) and Humes and Boxshall
Echinodermata, Polychaeta, Mollusca, Turbellaria, and (1996).
Nemertea (Boxshall and Halsey, 2004), but some of them
have been found in plankton. More than 70% of the species
in the genus have been recorded from tropical waters. In SYSTEMATIC ACCOUNTS
the present paper, nine new species of Pseudanthessius are
described from tropical regions of the Philippines, Vietnam, Order Cyclopoida Burmeister, 1834
Thailand, and Kosrae Island in Micronesia. Family Pseudanthessiidae Humes and Stock, 1972
Genus Pseudanthessius Claus, 1889
MATERIALS AND METHODS Pseudanthessius boholensis n. sp. (Figs. 1, 2)
Copepod specimens studied in the present work were extracted Material examined. 5♀♀ from washings of invertebrates,
from washings of invertebrates or intertidal invertebrate SCUBA, depth 28 m, 09°43ʹ02ʺN, 124°32ʹ17ʺE, Anda,
burrows or collected by a light trap. Collected specimens were Bohol Island, the Philippines, coll. Lee J & Kim IH, 4 Apr
fixed and preserved in 80% ethanol. Then, the specimens 2016. Holotype (♀, MABIK CR00247462) and paratypes
were immersed in lactic acid before microscopic observation (3♀♀, MABIK CR00247463) have been deposited in the
and dissection. Dissections were performed using the reverse Marine Biodiversity Institute of Korea (MABIK), Seocheon,
This is an Open Access article distributed under the terms of the Creative *To whom correspondence should be addressed
Commons Attribution Non­Commercial License (http://creativecommons.org/ Tel: [phone], Fax: [phone]
licenses/by­nc/3.0/) which permits unrestricted non­commercial use, distribution, E-mail: [email protected]
and reproduction in any medium, provided the original work is properly cited.
eISSN 2234-8190 Copyright The Korean Society of Systematic Zoology
Jimin Lee, Il-Hoi Kim
Fig. 1. Pseudanthessius boholensis n. sp., female. A, Habitus, dorsal; B, Urosome, dorsal; C, Anal somite and caudal rami, ventral;
D, Rostral area, ventral; E, Antennule; F, Antenna; G, Labrum; H, Mandible; I, Maxillule; J, Maxilla. Scale bars: A 0.1 mm, B, D,
E 0.05 mm, C, F-J 0.02 mm.
=
= =
288 Anim. Syst. Evol. Divers. 37(4), 287-321
New Species of Pseudanthessius from Tropical Waters
Fig. 2. Pseudanthessius boholensis n. sp., female. A, Maxilliped; B, Leg 1; C, Leg 2; D, Endopod of leg 3; E, Leg 4; F, Left leg 5 and
genital aperture, dorsal. Scale bars: A-F 0.02 mm.
=
Korea. Dissected paratype (♀) is retained in the collection Second to fourth pedigerous somites much narrower than
of IHK. cephalothorax. Urosome (Fig. 1B) stout, 5­segmented. Fifth
Female. Body (Fig. 1A) with swollen, globular cephalothorax. pedigerous somite 95 μm wide, bearing 1 dorsolateral and 2
Body length 836 μm. Prosome 573 μm long, occupying about lateral, naked setae. Genital double­somite slightly wider than
69% of body length. All prosomal somites with round lateral long (110 117 μm), laterally expanded, with convex lateral
corners. Cephalothorax inflated, globular, 389 436 μm. margins, widest at 60% region of double­somite length;
×
×
Anim. Syst. Evol. Divers. 37(4), 287-321 289
Jimin Lee, Il-Hoi Kim
genital apertures large, positioning almost dorsally at widest Coxa Basis Exopod Endopod
region. Three free abdominal somites much shorter than Leg 1 0-1 1-0 I-0; I-1; III, I, 4 0-1; 0-1; I, 1, 4
wide, 23 64, 18 59, and 26 56 μm, respectively. Anal Leg 2 0-1 1-0 I-0; I-1; III, I, 5 0-1; 0-2; I, II, 3
somite (Fig. 1C) ornamented with 7 or 8 dentiform spinules Leg 3 0-1 1-0 I-0; I-1; III, I, 5 0-1; 0-2; I, II, 2
× × ×
along each side of posteroventral margin. Caudal ramus (Fig. Leg 4 0-1 1-0 I-0; I-1; II, I, 5 0, 2, 0
1C) wider than long (22 24 μm), with smooth posteroventral
Leg 5 (Fig. 2F) consisting of 3 naked setae (1 smaller
margin.
× dorsolateral and 2 larger distal) on lateral process of fifth
Rostrum (Fig. 1D) broad; its lateral margin distinct, but
pedigerous somite. Leg 6 (Fig. 2F) on genital operculum
posterior margin faint, straight. Antennule (Fig. 1E) 244 μm
represented by 1 denticle and 2 small setae tipped with
long, 7­segmented; armature formula 4, 13, 6, 3, 4
setule.
aesthetasc, 2 aesthetasc, and 7 aesthetasc; all setae
+ Male. Unknown.
naked; several larger setae wrinkled; terminal segment very
+ + Etymology. The geographic name of the type locality is
short, half as long as penultimate segment. Antenna (Fig.
taken for the name of the new species.
1F) moderately stout, 4­segmented, consisting of coxobasis
Remarks. Pseudanthessius boholensis n. sp. most closely
and 3­segmented endopod; armature formula 2, 2, 3, and
resembles P. madrasensis Reddiah, 1968, which was
5 2 claws; coxobasis the longest; first and third endopodal
redescribed by Humes and Ho (1970). They have in common
segments with spinulose outer margin; third endopodal
+ a swollen cephalothorax, short caudal rami, identical forms
segment slightly arched, 2.37 times longer than wide (64 27
of the antenna and mandible (especially a broad outer scale
μm); 2 terminal claws very unequal in length and thickness,
× on the convex side of the latter oral appendage), two setiform
both strongly curved.
distal elements on the endopod of leg 4, and two distal setae
Labrum (Fig. 1G) with deep, narrow posteromedian
on leg 5. Nevertheless, a careful comparison of these leads to
incision; posterolateral lobes slightly divergent, with mem­
a determination that they are different in details and not the
branous fringe along posterior margin and sharp point on
same species.
inner margin. Mandible (Fig. 1H) with short, tapering distal
The differences in the female are (1) the body length of
lash and distinct inner proximal notch; inner margin of
the female is about 0.84 mm in the new species, compared
gnathobase with raw of small spinules; convex outer margin
to 0.63-0.73 mm in P. madrasensis measured by Humes
with membranous fringe and 1 large scale bearing pointed
and Ho (1970); (2) the caudal ramus is 0.9 times longer than
apex; convex margin of gnathobase with numerous fine
wide (22 23 μm) in the new species, compared to 1.14 times
striations. Maxillule (Fig. 1I) as small lobe bearing 4 naked
longer than wide (25 22 μm) in P. madrasensis; (3) the
unequal setae, second outer one of them longest. Maxilla (Fig. ×
anal somite of the new species is ornamented with prominent
1J) 2­segmented; syncoxa (proximal segment) unarmed; basis ×
spinules along the posteroventral margin, but Humes and Ho
(distal segment) with elongate, spinulose distal lash and 2
described that the margin of P. madrasensis is naked; (4) the
setae; seta I (inner seta) long, bipinnate; seta II (anterior seta)
distal segment (basis) of the maxilla bears setae I and II in the
unilaterally pinnate; seta III absent; distal lash bearing 3 or
new species, but one of these setae absent in P. madrasensis
4 large teeth (or spines) proximally and 2 small denticles on
according to fig. 11 of Humes and Ho (1970); (5) the
proximal anterior surface. Maxilliped (Fig. 2A) 3­segmented;
spiniform distal process of the maxilliped is spinulose in the
syncoxa (first segment) the longest but unarmed; basis (second
new species, but naked in P. madrasensis; (6) the endopodal
segment) with 2 subequal, naked setae; endopod (third
segment of leg 4 is 2.82 times longer than wide (48 17
segment) tapering, with spiniform distal process bearing 3
μm) in the new species, compared to 4.43 times longer than
denticles, 1 small spine, and 1 modified seta bearing droplet- ×
wide (62 14 μm) in P. madrasensis, despite that the latter
like expansion distally.
species is smaller than the new species; and (7) the distal
Legs 1-3 (Fig. 2B-D) with 3­segmented rami. Leg 4 (Fig. ×
margin of the endopodal segment of leg 4 is smooth in the
2E) with 3­segmented exopod and 1­segmented endopod.
new species, but ornamented with spinules in P. madrasensis.
Outer distal corners of endopodal segments of legs 1-3
These differences are sufficient to clearly differentiate the two
with well­developed, pointed process. Leg 4 endopodal
species.
segment 2.82 times longer than wide (48 17 μm), distally
armed with 2 setae, setulose along outer and inner margins,
× Pseudanthessius angustus n. sp. (Figs. 3, 4)
without denticle or notch on outer margin; 2 distal setae 30
μm (outer) and 47 μm (inner), inner seta spiniform, bearing Material examined. 2♀♀ from the echinoid Echinometra
fine spinules along distal half. Armature formula for legs mathaei (Blainville, 1825), intertidal, Anda, Bohol, the Phili­
1-4 as follows: ppines, 09°45ʹN, 124°35ʹE, coll. Lee J & Kim IH, 1 Apr 2016.
290 Anim. Syst. Evol. Divers. 37(4), 287-321
New Species of Pseudanthessius from Tropical Waters
Holotype (♀, MABIK CR00247464) has been deposited half as long as seta I, finely spinulose along its inner margin;
in the Marine Biodiversity Institute of Korea (MABIK), seta III vestigial, obscure. Maxilliped (Fig. 3K) 3­segmented;
Seocheon, Korea. Dissected paratype (♀) is retained in the syncoxa (first segment) unarmed; basis (second segment)
collection of IHK. armed with 2 large setae, proximal one of them extremely
Female. Body (Fig. 3A) narrow. Body length 1.01 mm. long, directed proximally, about 1.5 times longer than basis,
Prosome 654 μm long. Greatest width of prosome 373 μm. 2.5 times longer than nearby seta; endopod (third segment)
Prosomal somites with pointed or angular posterolateral small, beak­like, proximally with 1 small spine and 1 small
corners. Urosome (Fig. 3B) 5­segmented. Fifth pedigerous seta.
somite 119 μm wide. Genital double-somite 1.38 times Legs 1-3 (Fig. 4A-C) with 3­segmented rami. Leg 4 (Fig.
longer than wide (142 103 μm), narrower than fifth pedi- 4D) with 3­segmented exopod and 1­segmented endopod.
gerous somite, consisting of slightly expanded anterior three­ Inner coxal seta pinnate in legs 1-3, but naked, setule­like in
×
quarters and narrower distal quarter; lateral margins of leg 4. Outer seta on basis naked in legs 1-4, rudimentary in
anterior part curvy, with semicircular lateral expansion just leg 1, but large in legs 2-4. Leg 4 endopodal segment 3.89
posterior to genital aperture; genital aperture positioning times longer than wide (74 19 μm), with 2 distal spines,
dorsolaterally at 57% region of double­somite length. Three 1 cusp in middle of outer margin, naked inner margin, and
×
free abdominal somites 40, 26, and 35 μm long, respectively. setulose outer margin; 2 distal spines 36 (outer) and 54 (inner)
Anal somite unornamented, without any spinules along μm long, respectively. Armature formula for legs 1-4 as
posteroventral margin. Caudal ramus (Fig. 3C) 3.04 times follows:
longer than wide (73 24 μm), with 6 setae; outer lateral
Coxa Basis Exopod Endopod
seta (seta II) positioning 63% region of ramus length. Outer
× Leg 1 0-1 1-0 I-0; I-1; III, I, 4 0-1; 0-1; I, 1, 4
lateral and dorsal setae naked, other 4 setae pinnate.
Leg 2 0-1 1-0 I-0; I-1; III, I, 5 0-1; 0-2; I, II, 3
Rostrum (Fig. 3D) triangular, slightly wider than long,
Leg 3 0-1 1-0 I-0; I-1; III, I, 5 0-1; 0-2; I, II, 2
with blunt distal apex. Antennule (Fig. 3E) 303 μm long,
Leg 4 0-1 1-0 I-0; I-1; II, I, 5 0, II, 0
7­segmented; armature formula 4, 13, 6, 3, 4 aesthetasc,
2 aesthetasc, and 7 aesthetasc; all setae naked and thin, Leg 5 (Fig. 4E) consisting of 1 dorsolateral seta, 1 lateral
+
several of them very long; terminal segment short, less spine (37 μm long) and 1 lateral seta (45 μm long); all these
+ +
than half length of penultimate segment. Antenna (Fig. 3F) 3 elements naked. Leg 6 (Fig. 4E) represented by 2 small
slender, consisting of coxobasis and 3­segmented endopod; setae on genital operculum, proximal longer one of them
armature formula 1, 1, 2 claw, and 3 4 claws; first pinnate.
endopodal segment ornamented with fine spinules along Male. Unknown.
+ +
outer margin and inner seta on this segment small, not Etymology. The name of the new species is derived from
extending over distal margin of segment; third endopodal Latin angust (=narrow), depicting its narrow body.
segment 3.65 times longer than wide (62 17 μm); claws on Remarks. The most prominent diagnostic feature of Pseu­
distal endopodal segments slender, setiform, geniculate in danthessius angustus n. sp. is its possession of a pair of large
×
middle; 4 claws of third endopodal segment consisting of 2 setae on the basis of the female maxilliped, one of which
longer (inner second and fourth ones) and 2 shorter ones. is longer than the basis. Within the genus Pseudanthessius,
Labrum (Fig. 3G) bearing slightly divergent, rounded such a large seta in the same region is evident only in P.
posterolateral lobes fringed with membrane flange along remicaudatus n. sp. described below and P. sauvagei Canu,
posterior and inner margins; posteromedian incision deep. 1892, which was reported from the North­East Atlantic
Mandible (Fig. 3H) with curved, elongate distal lash, 1 (Canu, 1892; Sars, 1917). According to illustrations given by
proximal setiform spine on convex margin of gnathobase, Canu (1892) and Sars (1917) for P. sauvagei, in the female
obscure inner proximal notch; concave inner margin with of this European species (1) the lateral margins of the genital
5 spinules followed by several denticles. Maxillule (Fig. double­somite are smooth, in contrast to the curvy condition
3I) lobate, with 1 cusp in middle of outer margin, 1 broad, in P. angustus n. sp., (2) the caudal ramus is about twice
setiform process on inner margin, and distally with 3 setae as long as wide, while it is 3.04 times as long as wide in P.
including vestigial innermost one, other 2 distal ones broad, angustus n. sp., (3) the endopodal segment of leg 4 extends
unilaterally spinulose. Maxilla (Fig. 3J) consisting of syncoxa beyond the distal margin of the second exopodal segment,
and basis; syncoxa large, but unarmed; basis with elongate while it does not extend beyond the distal margin of the same
distal lash bearing row of about 14 spines, armed with 3 segment of P. angustus n. sp., and (4) the outer distal spine
setae; seta I (inner seta) large, basally broadened, spinulose of the endopod of leg 4 is longer than the inner distal spine,
along both margins; seta II, positioning proximally, about whereas the same spine of P. angustus n. sp. is shorter than
Anim. Syst. Evol. Divers. 37(4), 287-321 291
Jimin Lee, Il-Hoi Kim
Fig. 3. Pseudanthessius angustus n. sp., female. A, Habitus, dorsal; B, Urosome, dorsal; C, Left caudal ramus, dorsal; D, Rostrum; E,
Antennule; F, Antenna; G, Labrum; H, Mandible; I, Maxillule; J, Maxilla; K, Maxilliped. Scale bars: A 0.2 mm, B, D-F 0.05 mm, C,
G-K 0.02 mm.
= =
=
292 Anim. Syst. Evol. Divers. 37(4), 287-321
New Species of Pseudanthessius from Tropical Waters
Fig. 4. Pseudanthessius angustus n. sp., female. A, Leg 1; B, Leg 2; C, Endopod of leg 3; D, Leg 4; E, Left leg 5 and genital aper-
ture, dorsal. Scale bars: A-E 0.05 mm.
=
the inner distal spine. These differences indicate that they are Pseudanthessius firmus n. sp. (Figs. 5, 6)
not the same species.
A comparison between P. angustus n. sp. and P. remi­ Material examined. 2♀♀ from washings of invertebrates,
caudatus n. sp. will be made in the Remarks section of the Bohol Island, the Philippines, approximately 09°43ʹN,
latter species. 124°32ʹE, SCUBA, depth 14-26 m, coll. Lee J & Kim IH,
Anim. Syst. Evol. Divers. 37(4), 287-321 293
Jimin Lee, Il-Hoi Kim
2 Apr 2016. Holotype (♀, MABIK CR00247465) has been der than long, unarmed; basis (second segment) with 2 small
deposited in the Marine Biodiversity Institute of Korea setae and spinules on inner margin; endopod (third segment)
(MABIK), Seocheon, Korea. Dissected paratype (♀) is elongated, tapering, spiniform in distal region bearing
retained in the collection of IHK. densely arranged spinules along inner margin, proximally
Female. Body (Fig. 5A) stout, with thick, firm exoskeleton. armed with 1 spine and 1 seta.
Body length 1.40 mm. Prosome broad, 893 653 μm. Legs 1-3 (Fig. 6B-D) with 3­segmented rami. Leg 4
Prosomal somites with blunt or round posterolateral corners. with 3­segmented exopod and 1­segmented endopod. Inner
×
Cephalothorax divisible into cephalosome and first pedi­ coxal seta of leg 4 rudimentary. Outer seta on basis naked
gerous somite by weak dorsal suture line. Urosome (Fig. in all swimming legs. All other setae of these legs pinnate.
5B) 5­segmented, curved dorsally. Fifth pedigerous somite Endopodal segment of leg 4 about 3 times longer than wide
179 μm wide. Genital double-somite slightly wider than (91 30 μm), with smooth inner and outer margins lacking
long (147 157 μm), narrower than fifth pedigerous somite, setules or cusp; 2 distal spine 41 (outer) and 83 μm (inner),
×
consisting of slightly expanded anterior half and narrower respectively. Outer spine on first exopodal segment of leg
×
posterior half; genital apertures positioning dorsolaterally at 1 longer than other outer spines on exopods. Armature
53% region of double­somite length. Three free abdominal formula for legs 1-4 as in P. angustus n. sp.
somites 45 116, 34 110, and 68 106 μm, respectively. Leg 5 (Fig. 6F) consisting of 2 setae and 1 spine; dorso­
Anal somite unornamented, twice longer than second free lateral seta pinnate; lateral spine short, 26 μm long, and
× × ×
abdominal somite. Caudal ramus slightly divergent; each naked lateral seta 50 μm long. Leg 6 (Fig. 6F) consisting
ramus (Fig. 5B) 3.65 times longer than wide (157 43 μm), of 1 pinnate seta, 1 small, naked seta, and 1 small cusp on
with parallel lateral margins, armed with 7 setae, including genital operculum.
×
vestigial, setule­like seta I; seta II naked, positioning sub­ Male. Unknown.
distally. Etymology. The new species has the thick, firm exoskeleton,
Rostrum (Fig. 5C) semicircular, strong. Antennule (Fig. hence its name.
5D) 303 μm long, 7-segmented; armature formula 4, 13, Remarks. The peculiar armature condition of the antenna
6, 3, 4 aesthetasc, 2 aesthetasc, and 7 aesthetasc; 2 alone may characterize P. firmus n. sp., in which one of
terminal segments short, each wider than long, less than half setae on the second endopodal segment is elongated and
+ + +
as long as fifth segment. Antenna (Fig. 5E) 4­segmented; tipped with an adhesion pad and one of three distal claws
armature formula 1, 1, 3, and 3 3 claws; setae on coxo­ on the third endopodal segment is modified to a hook, as
basis and first endopodal segment very small; one of setae described above. This armature condition of the antenna has
+
on second endopodal segment elongated, extending beyond not yet been found in Pseudanthessius.
distal margin of third endopodal segment, peculiarly tipped As another remarkable morphological feature of P.
with adhesion pad (Fig. 5F); third endopodal segment 4.08 firmus n. sp., its maxilla does not have the inner seta (seta
times longer than wide (98 24 μm), claws unequal, lacking I) on the basis. Within the genus, nine species have been
annulation, outermost one of them recurved in distal part, reported to exhibit the same feature: P. exilicornis Stock
×
hook­like (Fig. 5F). & Humes, 1995; P. implanus Humes, 1977; P. pectinifer
Labrum (Fig. 5G) with semicircular, rounded postero­ Stock, Humes & Gooding, 1964; P. pictus Humes, 1977;
lateral lobes bearing fine spinules along their inner margin; P. procurrens Humes, 1966; P. pusillus Humes, 1969; P.
posteromedial incision deep. Mandible (Fig. 5H) with spinosus Shin & Kim, 2004; P. vinnulus Humes, 1977; and
elongate, finely spinulose distal lash; convex outer margin of P. weberi Scott A., 1909 (A. Scott, 1909; Stock et al, 1964;
gnathobase toothed, with numerous denticles, proximalmost Humes, 1966, 1969, 1977; Stock and Humes, 1995; Shin
one of them pale, transparent; inner margin short, densely and Kim, 2004). Interestingly, most of these nine species are
spinulose, with about 15 spinules; inner proximal notch associated with echinoids (except for P. weberi, which was
shallow, indistinct. Maxillule (Fig. 5I) with 4 setae (2 apical, found from washings of invertebrates), although another six
1 subdistal, and 1 on inner margin); subdistal seta the species associated with echinoids possess the usual maxillary
largest, finely spinulose, other 3 setae naked. Maxilla (Fig. armature. All of the above nine species lack a claw on the
5J) with unarmed syncoxa; basis with extremely long distal second endopodal segment of the antenna and two or three
lash bearing 2 rows of spinules along outer margin and fine (less than four) terminal claws on the antenna, and a plain,
setules along inner margin and armed with 1 feebly pinnate unmodified anterior seta (seta II) on the maxillary basis.
anterior seta (seta II); setae I and III absent. Maxilliped Three of the above nine species, P. procurrens, P. vinnulus,
(Fig. 6A) robust, strongly curved between first and second and P. weberi, are comparable with P. firmus n. sp., because
segments, 3­segmented; syncoxa (first segment) much broa- they have similar length/width ratios (a range between 3.0
294 Anim. Syst. Evol. Divers. 37(4), 287-321
New Species of Pseudanthessius from Tropical Waters
Fig. 5. Pseudanthessius firmus n. sp., female. A, Habitus, dorsal; B, Urosome, dorsal; C, Rostral area, ventral; D, Antennule; E, An-
tenna; F, Distal part of antenna; G, Labrum; H, Mandible; I, Maxillule; J, Maxilla. Scale bars: A 0.2 mm, B, C 0.1 mm, D, E 0.05
mm, F-J 0.02 mm.
= = =
=
Anim. Syst. Evol. Divers. 37(4), 287-321 295
Jimin Lee, Il-Hoi Kim
Fig. 6. Pseudanthessius firmus n. sp., female. A, Maxilliped; B, Leg 1; C, Leg 2; D, Endopod of leg 3; E, Leg 4; F, Left leg 5 and
genital aperture, dorsal. Scale bars: A 0.02 mm, B-F 0.05 mm.
= =
and 5.0) of caudal rami. Pseudanthessius firmus n. sp. can from washings of invertebrates, SCUBA, depth 15-30 m,
be easily distinguished from these three species by its robust Anda, Bohol, the Philippines, 09°43ʹ11ʺN, 124°32ʹ43ʺE,
female maxilliped and other differences, in addition to the coll. Lee J & Kim IH, 1 Apr 2016. Holotype (dissected
characteristic armature of the antenna. and mounted on a slide) has been deposited in the Marine
Biodiversity Institute of Korea (MABIK), Seocheon, Korea.
Pseudanthessius ardius n. sp. (Figs. 7, 8) Female. Body (Fig. 7A) slender. Body length 818 μm.
Prosome 488 μm long. Cephalothorax longer than wide
Material examined. 1♀ (holotype, MABIK CR00247466) (336 258 μm). Posterolateral corners angular in second
×
296 Anim. Syst. Evol. Divers. 37(4), 287-321