Candona improvisa Ostermeyer, 1937

Karanovic, Ivana & Lee, Wonchoel, 2012, A review of candonid ostracods (Crustacea: Ostracoda: Podocopida) from East Asia, with descriptions of five new species from South Korea *, Zootaxa 3368, pp. 7-49 : 20-21

Candona improvisa Ostermeyer, 1937

( Figure 8 )

Synonymy. Candona improvisa Ostermeyer, 1937 : p.155, Fig. 1 . Candona improvisa Ostermeyer : Meisch (2000), p. 73, Fig. 25.

Material Examined. Lectotype (here designated), male ( ZMH 421a, soft parts dissected on one slide, shell not preserved); and paralectotype (here designated), female ( ZMH 421b, soft parts dissected on one slide, shell not preserved), from (type locality) Germany, Saxony-Anhalt, Passendorfer Wiese, Halle a. S.

Redescription. Male. A1. Appendage 7-segmented. First segment with two setae anteriorly and two posteriorly. One anterior seta situated more proximally, the other distally on segment. Posterior setae originate from same (or very close) spot. All setae pappose. Second segment with one anterior pappose seta, not exceeding distal end of same segment. Third segment with one anterior, long and pappose seta slightly exceeding distal margin of fifth segment. Fourth segment with one short posterior seta (exceeding distal end of the same segment), and two anterior, longer setae (exceeding distal end of terminal segment). Fifth segment with same chaetotaxy as fourth one, except that posterior seta 1.5 times longer than that on previous segment. Penultimate segment with total of five setae; posteriormost seta “d” present. Alpha seta slightly exceeding distal end of terminal segment. Seventh segment with posterior, claw-like seta which is twice as long as terminal segment, one aesthetasc (ya) as long as terminal segment, and two other setae, one being slightly longer than claw-like seta, the other being much longer. L ratio of five distal segments equaling: 1: 1.4: 1.6: 2: 1.8. Rome and Wouters organs not present.

A2 ( Figure 8 E). Basal segment (not illustrated) with total of three setae: one short, the other two longer. One of the long setae situated dorsally and one ventrally on segment. Distal segment of protopod with one, distally pappose seta exceeding distal margin of fourth endopodal segment. Exopod consisting of plate carrying one long (almost reaching distal end of first endopodal segment) and two short, pappose setae. Endopod 4-segmented, penultimate segment being divided, carrying two male sexual bristles. First endopodal segment with aesthetasc “Y” and antero-ventrally with two long setae (almost equally long). Second segment with one medio-dorsal (t4) seta, setae t3 and t2 transformed into sexual bristles (exceeding distal end of terminal segment) and one anteroventral seta (t1). Same segment medio-ventrally with short aesthetasc y1. Third endopodal segment with claws G1, G2, G3, z1 and z2, and seta z3. Claws G1 and G3 short (60% of first endopodal segment): G2 long (1.1 times longer than first endopodal segment); z1 equaling 2/3 of z2 and latter approximately as long as fist endopodal segment; z3 thin seta and half as long as z2 claw. Terminal segment with one long claw, Gm (approximately as long as first endopodal segment) and one short claw, GM (1.5 times longer than terminal segment). Terminal segment also armed with aesthetasc y3 (as long as terminal segment) and one thin seta accompanying y3. Claws very gently serrated.

Md. First segment of palp with one plumose seta (S1) and one pappose seta, and short alpha seta. Second segment dorsally with two setae, exceeding distal end of following segment, ventrally with pappose beta seta, five setae originating from a small plate and one plumose seta. Penultimate segment dorsally with three setae of which two are subequally long, and one almost half as long; gamma seta plumose, and three additional setae of which one originating medially and two ventrally. Terminal segment with two strong, well-sclerotized claws and two setae more ventrally.

Mxl. Palp 2-segmented, first segment with four setae: three originating antero-distally, and one medio-distally. All these setae pappose. Terminal segment with two claw-like setae and four setae, one situated between claws, and three situated more posteriorly.

Prehensile palps ( Figure 8 C, D). Palps asymmetrical, right one with more curved dorsal margin. Finger on left palp much longer than body. Both palps with well-developed subterminal structures.

L6. Basal segment with one seta (d1). Endopod 4-segmented. Seta “e” and “f” reaching distal margins of their corresponding segments, seta “g” exceeding distal end of terminal segment. Terminal segment with distal claw and two lateral, short setae (h1 and h3). Distal claw approximately as long as combined L of three distal segments.

L7. Basal segment with “d1” and “dp” setae. Seta “d2” missing. Endopod 4-segmented, and only “g” seta present distally. Terminal segment armed with two long and one very short seta (h1). L ratios between three “h” setae equaling: 1: 3.2: 4. Seta “h1” three times longer than terminal segment.

UR ( Figure 8 F). Symmetrical; posterior seta not very long and only reaching postero-distal margin of the ramus. Anterior seta much shorter and only ¼ L of anterior claw. Both claws faintly serrated. L ratio between anterior margin, anterior claw, posterior claw and posterior seta equaling: 2.2: 1.3: 1.15: 1.

Hemipenis ( Figure 8 A, B). Medial lobe well-sclerotized with boxer glove-like, broadly rounded distal end. Lobe “h” slightly pointed on its distal end. Lobe “a” subdivided into two sub-lobes, more dorsal subquadrate distally and with small protrusion proximally, lower square-shaped. Inner duct not coiled.

Zenker organ with seven rows of spines.

Female. A2. Endopod 3-segmented. All four “t” setae on penultimate segment present, subequally long and pappose; three of those exceeding distal end of terminal segment. None of “z” setae transformed into claws exceeding distal end of terminal segment. Claw G2 equaling 2/3 of claw G1 which is slightly longer than first endopodal segment. Claw G3 same as claw G1. Terminal segment with long claw Gm and short Gm. All claws gently serrated.

L5. One “a”, “b” and “d” setae present. Terminal setae on endopod short, two subequally long, one slightly longer.

L7 ( Figure 8 G) same as in male.

UR ( Figure 8 H) Similar to male. Ramus much wider proximally than in males. L ratios between anterior margin, anterior, posterior claw and posterior seta equaling: 2.9: 1.35: 1: 1.

Genital field ( Figure 8 H). On one field two projections present, both triangular in shape, on other field the projection closer to ramus apparently missing (maybe destroyed during dissection), the other same as on previous field.

All other appendages same as in male.

Figures

FIGURE 1. Candona quasiakaina sp. nov., A, holotype (male); B, C, allotype (female): A, carapace, lateral exterior view from the right side with Zenker organ indicated; B, LV, exterior view; C, RV, interior view. B and C with ovary indicated. Scales = 0.1 mm.

FIGURE 8. Candona improvisa Ostermeyer, 1937, A – F lectotype (male) (ZMH 421 a); G, H paralectotype (female) (ZMH 421 b): A, details of the hemipenis; B, hemipenis, general view; C, right prehensile palp; D, left prehensile palp; E, A 2; F, UR; G, distal part of L 7; H, UR with genital field. Scales = 0.1 mm.