Sarsiella misakiensis Kajiyama, 1912, Kajiyama, 1912

Karanovic, Ivana & Soh, Ho-Young, 2015, Five Sarsiellidae ostracods (Crustacea: Myodocopida) from the South Coast of Korea (East China Sea), Zootaxa 3947 (4), pp. 451-488: 470-476

publication ID

http://dx.doi.org/10.11646/zootaxa.3947.4.1

publication LSID

lsid:zoobank.org:pub:E0151A24-761D-4465-BB71-DAC4FA5B9550

DOI

http://doi.org/10.5281/zenodo.5658727

persistent identifier

http://treatment.plazi.org/id/E2798D5D-4A64-FFD0-C8D7-52782AEEF92B

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Plazi

scientific name

Sarsiella misakiensis Kajiyama, 1912
status

 

Sarsiella misakiensis Kajiyama, 1912  

( Figures 13–17 View FIGURE 13 View FIGURE 14 View FIGURE 15 View FIGURE 16 View FIGURE 17 )

Synonymy. Sarsiella misakiensis   n.sp. — Kajiyama 1912: p. 615, Figs 23 View FIGURE 23 –28, Plate 9; Sarsiella misakiensis Kajiyama—Hiruta 1978   : p. 261, Figs 1–15 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 View FIGURE 9 View FIGURE 10 View FIGURE 11 View FIGURE 12 View FIGURE 13 View FIGURE 14 View FIGURE 15 .

Material examined. Three females dissected on three slides, shells on micropaleontological slides ( NIBR IV 0 0 0 0 287241, NIBR IV 0 0 0 0 287242, and NIBR IV 0000287243); one female on SEM stub; from South Korea, East China Sea, Maemul Island, 34 ° 36 ’ 47 ”N 128 ° 20 ’ 46 ”E, 0 7 September 2012, collector H. Y. Soh.

Description. Female. Shell ( Figures 14 View FIGURE 14 A, D; 15 A) with several irregular ridge-like structures, giving bumpy appearance. Surface covered with wide, shallow pits (fossae) ( Figure 15 View FIGURE 15 B), and extremely densely with longer and shorter spines and setae. Caudal process ( Figures 13 View FIGURE 13 A; 14 B, C) not very long and distally not sharply pointed. Postero-dorsal bulge slightly overpassing dorsal margin, and square-like. Dorsal margin of carapace straight in posterior part, rounded in medial and anterior parts. Ventral margin rounded. Long pore canals lead from posterior process to inside of valves, shorter ones present along entire anterior and ventral margin. Anterior infold without bristles. Infold of caudal process with several short bristles running along caudal process, one row of short bristles lying proximally and (further proximal) several scattered, even shorter bristles. Shell L (including caudal process)= 1.6 mm.

A 1 ( Figures 15 View FIGURE 15 C–E). First segment long and bare. Second segment with annulated, bare, dorsal bristle reaching 1 / 3 of following segment. Third and fourth segment fused; third with annulated, bare dorsal bristle reaching distal margin of same segment and no ventral bristle. Fourth segment with bare, annulated dorsal bristle not reaching distal end of following segment, and two, annulated bristles ventrally (subequally long; Figure 15 View FIGURE 15 D). Fifth and sixth segments fused. Bristle of fifth segment long, annulated and bare; seta on sixth segment short, also bare. Seventh segment: a-bristle about five times longer than sixth segment’s bristle; b-bristle slender, and about as long as a-bristle; bristles from b- to g- all almost subequally long, all without sensory setae.

Bellonci Organ ( Figure 15 View FIGURE 15 C, F). Cylindrical, not segmented and short, distally with small pointed tip.

Eyes. Both medial and lateral eyes present. Medial eye with scattered pigment, lateral eye with four ommatidia.

A 2 ( Figure 16 View FIGURE 16 A–C). Prp bare. Enp with two short basal bristles (annulated and bare), and no bristles situated on terminal node. Exp: first segment with small terminal medial recurved tubular bristle; bristle on second segment with thick proximal ventral spines and distal swimming setae; bristles on segments 3–8 without thick spines proximally and with swimming setae distally; ninth segment with two bristles (one short, bare and other longer with swimming setae).

Md ( Figure 16 View FIGURE 16 D–F). Cx endite elongated and with short spine-like setae, Cx with long slender spines near ventral margin. Bs: ventral margin with three short bristles. Exp present ( Figure 13 View FIGURE 13 B) and consisting of small segment with several short bristles at its tip. First Enp segment with one stout claw distally; second Enp segment with strong claw ventrally, and one tiny spine dorsally; third Enp segment with stout terminal claw and small dorsal and ventral spines.

Mxl ( Figure 14 View FIGURE 14 F, G). Cx with long, bare dorsal bristle. Endite I with total of 10 claws/bristles; endite II with one claw, three bristles; endite III with two claws and one bristle. Exp with two bristles: one long and one short. First Enp segment with spinous alpha- and beta-bristles. Second Enp segment with five pectinate claws, two a- and one c-bristle.

L 5 ( Figure 17 View FIGURE 17 D). Lobe one with one short bristle; lobe two with two bristles (one longer than other); lobes 3–5 fused and with total of seven bristles, five long and annulated and with setulae, two bare, short bristles. Entire appendage hirsute.

L 6 ( Figure 17 View FIGURE 17 B). One endite with three ringed, bare bristles. Terminal segment with 10 annulated bristles, each with short setulae, and almost all of same length. Ten bristles followed by space and two long plumose bristles. Entire appendage covered with fine, short setulae.

L 7 ( Figures 13 View FIGURE 13 C, 17 E). Proximal group with two bristles (one on each side) each with five bells. Terminal group with three bristles on each side, each with three or six bells. Terminus without opposing combs.

UL ( Figure 13 View FIGURE 13 D, 17 A, C). Each lamella with five claws. Only claw one non-articulated; claws with long and short teeth along posterior edge. Right lamella with first claw always less serrate than on left lamella, left lamella with short spines.

Remarks. Sarsiella misakiensis   was reported twice from Japan ( Kajiyama 1912, Hiruta 1978), the second finding also with a detailed redescription and description of larval stages. The following are the differences between the present finding in Korea and the species first redescription ( Hiruta 1978):

1. According to Hiruta (1978) the surface is covered with fibrous structures, while we were able to clearly observe spines and setae of different length. However, they are indeed very dense and this may provide an appearance of undifferentiated fibrous structures;

2. The ventral bristle on the third A 1 segment is present in the Japanese population;

3. Hiruta (1978) did not observe the Md Exp, but this can only be seen using SEM.

All other appendages are almost identical with the Korean finding and therefore we consider these two populations to be conspecific.

NIBR

National Institute of Biological Resources