Demoixys depressa Kim & Boxshall 2020, sp. nov.
Creators: name: Kim, Il-Hoi
name: Boxshall, Geoff A.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Copepoda
Cyclopoida
Notodelphyidae
Demoixys
Demoixys depressa

description: Demoixys depressa sp. nov.
(Figs. 365, 366)
Typematerial. Holotype (intact ♀, MNHN-IU-2014- 21407), paratypes (2 intact ♀♀, MNHN-IU-2014-21408), and dissected paratypes (2 ♀♀, figured) from Diplosoma versicolor Monniot F., 1994 (MNHN-IT-2008-3648 = MNHNA 2/ DIP /147), CRRFCRCHO 139, Caminguin I., the Philippines (09°12.89’N, 124°38.03’E), 18 April 1997.
Etymology. The specific name alludes to the dorsoventrally depressed body of the new species.
Descriptionoffemale. Body (Fig. 365A, B) swollen, 1.94 mm long. Prosome curved ventrally, depressed, makedly broaderposteriorly, 1.03 mm wide, and 0.79 mm dorsoventral depth. Cephalosome directed posteriorly; dorsal cephalic shield distinct, small in relation to metasome, lacking posterolateral processes. Metasome unsegmented, with 2 dorsal constrictions anteriorly; posterolateral part more expanded than anterior and middle regions; entire metasome forming brood pouch. Freeurosome (Fig. 365C) short, slightly widerthan long, 5-segmented, but genital somite fused with metasome. Caudal rami fused with anal somite, without trace of articulation, strongly tapering, nearly as long as wide, setulose but lacking setae.
Rostrum (Fig. 365D) large, slightly wider than long, semicircular, with scattered setules. Antennule (Fig. 365E) short, broad, 90 μm long, 1.5 times longer than wide, incompletely 5-segmented; articulations expressed only on posterior surface of appendage; few setae indistinguishable from scattered setules. Antenna (Fig. 365F) 3-segmented, consistingof coxa, basis, and unsegmentedendopod; coxaandbasisunarmed; endopod about 2.7 timeslongerthan wide (41×15 μm): armed with 5 setae (arranged as 1, 2, and 2) plus short terminal claw, aboutone-thirdaslongas endopod.
Labrum (Fig. 365G) semicircular, much widerthan long, unornamented. Mandible (Fig. 365H) with broad coxal gnathobase bearing 4 teeth; proximal second tooth smaller: basiswith 1 seta medially; exopod with 5 setae; proportional lengths of setae 12:13:15:16:10 from inner to outer; endopod with 1 broad seta on first segment and 4 (2 medial and 2 distal) subequal setae on second. Maxillule (Fig. 365J) with 7 setae on arthrite, 1 on each epipodite and basis, 4 on exopod, and 3 on endopod; endopod incompletely defined from basis; coxal endite absent. Maxilla (Fig. 365I) 3-segmented; syncoxawith 3, 2, and 2 setae on first to third endites, respectively; basis with claw plus 1 seta; endopod unsegmented with 4 setae. Maxilliped (Fig. 366A) as small lobe armed with 6 naked setae.
Legs 1–3 (Fig. 366 B–D) rudimentary, each represented by 2 unsegmented lobes; coxa and basis not defined. Leg 1 with 9 setae on exopodal lobe and 4 on endopodal lobe. Leg 2 with 7 setae on exopodal lobe and unarmed endopod. Leg 3 with 4 setae on exopodal lobe and 2 setae on endopodal lobe. Setae on legs 1–3 small or rudimentary. Legs 4 and 5 absent.
Male. Unknown.
Remarks. Demoixys depressa sp. nov. may be distinguished from its congeners by the absence of legs 4 and 5. The dorsoventrally depressed body and the possession of 4 setae on the unsegmented endopod of the maxilla are also distinguishing character states of the new species.
description: Published as part of Kim, Il-Hoi & Boxshall, Geoff A., 2020, Untold diversity: the astonishing species richness of the Notodelphyidae (Copepoda: Cyclopoida), a family of symbiotic copepods associated with ascidians (Tunicata), pp. 1-6 in Megataxa 4 (1) on pages 547-549, DOI: 10.11646/megataxa.4.1.1, http://zenodo.org/record/4591138