Sarsiella misakiensis, Karanovic, Ivana & Soh, Ho-Young, 2015

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

Sarsiella misakiensis Kajiyama, 1912

( Figures 13–17 )

Synonymy. Sarsiella misakiensis n.sp. — Kajiyama 1912: p. 615, Figs 23 –28, Plate 9; Sarsiella misakiensis Kajiyama—Hiruta 1978 : p. 261, Figs 1–15 .

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 A, D; 15A) with several irregular ridge-like structures, giving bumpy appearance. Surface covered with wide, shallow pits (fossae) ( Figure 15 B), and extremely densely with longer and shorter spines and setae. Caudal process ( Figures 13 A; 14B, 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.

A1 ( Figures 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 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 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.

A2 ( 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 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 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 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.

L5 ( 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.

L6 ( 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.

L7 ( Figures 13 C, 17E). 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 D, 17A, 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 A1 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.

Figures

FIGURE 1. SEM images: A, Eurypylus koreanus sp. nov., holotype female, RV, lateral view from the outside; B, Eusarsiella hanguk sp. nov., holotype female, LV, lateral view from the outside.

FIGURE 2. Eurypylus koreanus sp. nov., holotype female: A, LV, lateral view from the inside; B, detail of the caudal process from the inside; C, A 1 (arrow indicating Bellonci Organ); D, Enp and the first Exp segment of A 2; E, Md without Cx; F, Md Cx. Scales = 0.1 mm.

FIGURE 3. Eurypylus koreanus sp. nov., holotype female: A, Enp and Exp of Mxl (arrow indicating coxa); B, endites I and II of Mxl; C, L 5; D, distal part of L 7; E, L 6; F, UL. Scales = 0.1 mm.

FIGURE 4. Eusarsiella hanguk sp. nov., holotype female: A, LV, lateral view from the outside; B, RV, lateral view from the inside; C, L 6; D, detail of the caudal process of the LV (turned upside-down). Scales = 0.1 mm.

FIGURE 5. Eusarsiella hanguk sp. nov., holotype female: A, A 1 without distal part (Bellonci Organ part of this figure); B, distal segments on A 1; C, Enp and Exp on Mxl; D, Mxl endites. Scale = 0.1 mm.

FIGURE 6. Eusarsiella hanguk sp. nov., holotype female: A, Md; B, Enp of A 2; C, L 5; D, Exp of A 2; E, terminal segment of Exp A 2; F, bristle on the first segment of the Exp A 2. Scale = 0.1. mm.

FIGURE 7. Eusarsiella hanguk sp. nov., holotype female: A, UL; B, distal part of L 7. Scales = 0.1 mm.

FIGURE 8. SEM images of Sarsiella japonica Hiruta, 1977, female: A, whole animal, lateral view from the right side; B, detail of the caudal process RV; C, detail of the caudal process LV; D, E, details of the shell surface.

FIGURE 9. Sarsiella japonica Hiruta, 1977, female: A, A 1 without distal segments; B, RV, lateral view from the inside; C, detail of the caudal process, RV, inside view; D, RV, lateral view from the outside; E, Bellonci Organ. Scales = 0.1 mm.

FIGURE 10. Sarsiella japonica Hiruta, 1977, female: A, A 2; B, distal segments of A 1. Scale = 0.1 mm.

FIGURE 11. Sarsiella japonica Hiruta, 1977, female: A, Md Cx; B, Md without Cx; C, endites of Mxl; D, Mxl Enp, Exp and par of the endite I. Scale = 0.1 mm.

FIGURE 12. Sarsiella japonica Hiruta, 1977, female: A, UL; B, genital field; C, L 6; D, L 5; E, distal part of L 7. Scale = 0.1 mm.

FIGURE 13. SEM images of Sarsiella misakiensis Kajiyama, 1912, female: A, detail of the caudal process, RV, inside view; B, Md EXp; C, L 7; D, UL and Enp of Mxl.

FIGURE 14. Sarsiella misakiensis Kajiyama, 1912, female: A, LV, lateral view from the inside; B, detail of the caudal process, RV, inside view; C, detail of the caudal process, LV, inside view; D, RV, lateral view from the inside; E, part of the ventral margin of the shell, LV inside view; F, Endite I of Mxl; G, Endites II and III and Enp of Mxl. Scales = 0.1 mm.

FIGURE 15. Sarsiella misakiensis Kajiyama, 1912, female: A, LV, lateral view from the outside; B, detail of the surface ornamentation; C, Proximal part of A 1; D, distal part of A 1; E, A 1; F, Bellonci Organ. Scales = 0.1 mm.

FIGURE 16. Sarsiella misakiensis Kajiyama, 1912, female: A, A 2; B, C, distal segments of Exp A 2; D, Md Cx; E, Md without Cx; F, detail of the ventral margin of the Md Bs. Scales = 0.1 mm.

FIGURE 17. Sarsiella misakiensis Kajiyama, 1912, female: A, proximal part of UL with “ Y ” sclerite; B, L 6; C, UL; D, L 5; E, distal part of L 7. Scale = 0.1 mm.

FIGURE 23. Geographic distribution of Eusarsiella Kornicker & Cohen, 1975: 1: E. vema Kornicker, 1986; 2: E. disparalis (Darby, 1965); E. greyi (Darby, 1965); E. nodimarginis (Darby, 1965); E. radiicosta (Darby, 1965); E. tubipora (Darby, 1965); 3: E. pseudospinosa (Baker in Kornicker & Baker, 1977); E. thominx Kornicker, 1987; 4: E. maurae (Kornicker, 1977) Kornicker, 1986; 5: E. bakeri Kornicker, 1986; E. elofsoni Kornicker, 1986; E. dispar Kornicker, 1986; E. texana (Kornicker & Wise, 1962); E. gettlesoni Kornicker, 1986; 6: E. bryanjuarezi Churchill, Ellis, Pique & Oakley, 2014; E. eli Churchill, Ellis, Pique & Oakley, 2014; E. childi Kornicker, 1986; E. cresseyi Kornicker, 1986; E. culteri Kornicker, 1986; E. ozotothrix (Kornicker & Bowen, 1976); E. paniculata Kornicker, 1986; E. pilipollicis (Darby, 1965); E. spinosa (Kornicker & Wise, 1962); E. tampa Kornicker & Grabe, 2000; E. zostericola (Cushman, 1906); 7: E. athrix Kornicker, 1986; E. capillaris (Kornicker, 1958); E. carinata (Scott, 1905); E. costata (Kornicker, 1958); E. fax Kornicker, Iliffe & Harrison-Nelson, 2007; E. gigancantha (Kornicker, 1958); E. punctata (Kornicker, 1958); E. ryanae Kornicker & Iliffe, 2000; E. styx Kornicker & Iliffe, 1989; E. syrinx Kornicker, Iliffe & Harrison-Nelson, 2007; E. truncana (Kornicker, 1958); E. uncus Kornicker, 1986; E. warneri Kornicker, Iliffe & Harrison-Nelson, 2002; E. merx Kornicker, Illife & Harrison-Nelson, 2002; 8: E. alata (Poulsen, 1965) Cohen & Kornicker, 1975; E. cornuta (Poulsen, 1965); E. dentifera (Poulsen, 1965); E. dominicana Kornicker, 1986; E. ovalis (Poulsen, 1965); E. spicata (Poulsen, 1965); 9: E. donabbotti Cohen, 1989; 10: E. absens (Kornicker, 1981); 11: E. venezuelensis Kornicker, 1986; 12: E. zostericola (Cushman, 1906); 13: E. neapolis (Kornicker, 1974); 14: E. bedoyai Baltanas, 1992; 15: E. africana (Kornicker & Caraion, 1978); E. dornellasae (Kornicker & Caraion, 1978) Kornicker, 1986; E. gomoiui (Kornicker & Caraion, 1978); E. ocula (Kornicker & Caraion, 1978); E. rudescui (Kornicker & Caraion, 1978); 16: E. lunata (Kornicker, 1975); 17: E. falx Kornicker, 1992; 18: E. tumida (Scott, 1905); 19: E. longipenna Poulsen, 1965; E. rugosa (Poulsen, 1965); 20: E. microthrix (Chavtur, 1983); 21: E. hanguk sp. nov. 22: E. chessi Kornicker, 1991; 23: E. asciformis (Hall, 1987); E. claviformis (Hall, 1987); E. reticulata (Hall, 1987); E. serrata (Hall, 1987); E. springthorpei (Hall, 1987); 24: E. phrix Kornicker, 1996; E. saengeri Kornicker, 1996; E. tryx Kornicker, 1996; E. vernix Kornicker, 1996; 25: E. sculpta (Brady, 1890); 26: E. edax Kornicker, 1994; E. fallomagna Kornicker, 1994; E. magna Poulsen, 1965; 27: E. bex Kornicker, 1994; E. iayx Kornicker, 1994; 28: E. segrex Kornicker, 1995; E. spadix Kornicker, 1995; 29: E. antipex Kornicker, 1995; 30: E. janiceae (Kornicker, 1976).