Parasterope sohi, Pham & Karanovic, 2022

Pham, Huyen T. M. & Karanovic, Ivana, 2022, Four new Parasterope (Ostracoda, Myodocopina) from the Northwest Pacific and their phylogeny based on 16 S rRNA, ZooKeys 1095, pp. 13-42 : 13

Parasterope sohi sp. nov.

Figs 10 , 11

Specimens examined.

Holotype female dissected on one slide, shells on SEM stub (NIBR IV 0000887834). The sample was collected from the type locality: South Korea, Maemul Island, 34°32'00.4"N, 128°43'54.4"E, by Ho Young Soh on 25th July 2011.

Etymology.

The species named after Prof. Ho-young Soh (Faculty of Marin Technology, Chonam National University, Jeonnam, Korea), whom we are greatly indebted to for collecting and providing samples for this publication.

Diagnosis.

Carapace elongated. Surface of the shell completely smooth. Posterior end with a short, rounded incisure, while the anterior has relatively deep incisure. Dorsal and ventral margins rounded. Posterior end wider than anterior. Lateral eye well developed with black pigmented ommatidia.

Description.

Female. Shell (Fig. 10 ). Carapace oval, broadening at posterior, greatest height near middle, carapace length 1.48 mm, height 0.98 mm. Carapace smooth and without ornamentation.

A1 (Fig. 11a ). 1st joint: with no hair on broad surface and longer than 2nd joint. 2nd joint without spines along dorsal or ventral margin, one spinous dorsal seta, one short lateral bristle. 3rd joint: seven setae (one short ventral and six dorsal). 4th joint: three bristles (one long dorsal and two short ventral bristles). 5th joint: sensory bristle with six filaments without short proximal terminal. 6th joint: one medial seta, attached to bottom of 7th joint boundary. 7th joint: a-bristle claw-like, bare; b-seta with marginal filaments; c-seta with marginal filaments. 8th joint: d-bristle absent; e-bristle bare, with blunt tip; f- and g-bristles with marginal filaments.

Bellonci orange (Fig. 11b ). Elongate with rounded tip with unclear constriction.

Eyes. Lateral eye with 15 ommatidia.

A2 (Fig. 11c, d ). Protopodite: rounded. Endopodite (Fig. 11c ): 2-jointed, with long terminal bristle, ~ 1/3 of stem length. Exopodite (Fig. 11d ): 9-jointed; bristle of 2nd segment along ventral margin and spines along dorsal margin reaching 8th joint; 3th-8th joints with natatory hairs and spines along proximal part of ventral margin. 9th article: four bristles (two long natatory and two short bristles). 5th-8th joints with minute spines at inner terminal corner.

Md (Fig. 11e, f ). Coxale endite same as that on P. busanensis and P. singula . Basal endite (Fig. 11e ) with six spinous end bristles and one triaenid bristle with three spines excluding terminal pair. Basale dorsal margin with two long terminal setae, without mid-bristle. Exopodite with spine-like tip and small subterminal setae, exopodite just reaching past end of dorsal margin of the 1st endopodite article. Endopodite (Fig. 11f ): 1st joint: ventral margin with three long bristles with long marginal spines; 2nd joint: ventral margin: with three terminal bristles; dorsal margin: with stout a-, b-, c-, and d-bristles and with one short bristle proximal to a-bristle (missing on drawing line figure); one long e-bristle between b- and c-bristles; four medial cleaning bristles forming an oblique adjacent to b-bristle; five medial bristles forming an oblique row adjacent to c-bristle; f-bristle between c- and d-bristles, long, bare; g-bristle longer than f-bristle. 3rd segment with a strong dorsal claw-like bristle without marginal spines, three juxtaposed stout bristles of equal length, and two thin bristles.

Mxl. Endite unknown. Basale: one dorsal medial distal bristle. Endopodite: 1st with one short α-seta and one hairy β-seta; 2nd article with two terminal bristles.

L5. Unknown.

L6. Unknown.

L7. Unknown.

F. Unknown.

Male. Not collected.

Remarks.

The new species Parasterope sohi sp. nov. is poorly known because of the missing L5, L6, L7, and furca but we propose a new name because of the presence of the combination of the following characters: A1 sensory bristle carry 0+6 filaments; exopodite of Md is unusually long; and the Md endopodite has the e-bristle. In majority of Parasterope described so far, the mandible exopodite is at most longer than ½ length of the dorsal margin of the 1st endopodite joint; in P. sohi the exopodite length is greater than the length of the dorsal margin of the 1st endopodite joint. Other species with such a long exopodite include P. lagunicola from French Polynesia ( Hartmann 1984), P. omega Kornicker, Harrison-Nelson & Coles, 2007 from Hawaiian Islands ( Kornicker, Harrison-Nelson and Coles 2007), and P. sohni Kornicker & Caraion, 1974 from West Africa ( Kornicker and Caraion 1974). However, the first two species have small proximal spines on A1, absent in P. sohi. The last species has a mid-bristle on the dorsal margin of the basale, absent in P. sohi . Also, P. sohi differs from another Parasterope species by having six spinous end bristles and one triaenid bristle on the endite of the Md basale. All other Parasterope species are armed with at least four triaenid bristles.

GenBank number 16S: OK048685. 18S could not be obtained.

Figures

Figure 10. Light microscopy and scanning electron microscopy images of Parasterope sohi sp. nov. holotype female adult: a External view b Lateral view from left valve c Anterior of left valve from inside showing bristles of infold.

Figure 11. Parasterope sohi sp. nov. holotype female adult: a A 1 b bellonci organe c A 2 endopodite d A 2 exopodite e Md basale endite f Md endopodite. Scale bar: 0.1 mm.