Entocytherinae

Weaver, Patricia G. & Williams, Bronwyn W., 2017, A new genus and species of entocytherid ostracod (Ostracoda: Entocytheridae) from the John Day River Basin of Oregon, U. S. A., with a key to genera of the subfamily Entocytherinae, Zootaxa 4273 (4), pp. 576-586 : 577

Key to the genera of the subfamily Entocytherinae

(Modified after Hart & Hart 1974; Hobbs & Walton 1975; Hobbs & Peters 1977)

1 Penis with prostatic and spermatic elements widely separated along much of their lengths............................ 2

1’ Penis simple; or if two elements recognizable, contiguous along their length....................................... 4

2(1) Ventral portion of peniferum tapering into narrow projection with tip of penis reaching, or almost reaching, distal end................................................................................................. Plectocythere

2’ Ventral portion of the peniferum usually rounded or with one or more prominences, seldom tapering; if tapering, tip of penis never approaching distal end............................................................................. 3

3(2’) Ventral portion of the peniferum rounded, without prominences...................................... Phymocythere

3’ Ventral portion of peniferum with one or more prominences ventrally and/or anteriorly.................... Ascetocythere

4(1’) Penis directed posteroventrally from base........................................................ Lordocythere

4’ Penis directed anteroventrally from base................................................................... 5

5(4’) Finger guard present................................................................................... 6

5’ Finger guard absent................................................................................... 11

6(5’) Peniferum with accessory groove, except in Dactylocythere leptophylax where finger guard is always slender and trifid.... 7

6’ Peniferum without accessory groove; finger guard never slender and trifid........................................ 8

7(6) Posteroventral portion of peniferum terminating in barbed point...................................... Sagittocythere

7’ Posteroventral portion of peniferum variable, but never ending in barbed point.......................... Dactylocythere

8(6’) Ventral portion of peniferum bulbiform, clasping apparatus never extending as far ventrally as peniferum...... Cymocythere

8’ Ventral portion of peniferum slender, flared, or flattened: clasping apparatus extending ventrally to or beyond ventral extremity of peniferum......................................................................................... 9

9(8’) Ventral portion of peniferum flared and with concave ventral border; not terminating in projection............. Litocythere

9’ Ventral portion of peniferum terminating in projection....................................................... 10

10(9’) Ventral portion of peniferum slender, terminating in small recurved projection......................... Harpagocythere

10’ Ventral portion of peniferum broadly flattened, terminating in pointed anteroventral projection............. Waltoncythere

11(5’) Anteroventral portion of peniferum with acute beak-like projection................................... Ornithocythere

11’ Anteroventral portion of peniferum never with beak-like projection............................................. 12

12(11’) External border of horizontal ramus of clasping apparatus with talon or other excrescences.......................... 13

12’ External border of horizontal ramus of clasping apparatus entire or with few shallow subapical grooves................ 16

13(12) Anteroventral portion of peniferum produced ventrally in rounded lobe.......................................... 14

13’ Anteroventral portion of peniferum never produced ventrally in rounded lobe; if produced, distal end acute or truncate.... 15

14(13) Spermatic loop horizontal; peniferum distal to dorsal margin of spermatic loop at least twice as long as portion dorsal to loop; clasping apparatus with external border bearing single tubercle and terminating in fan-like cluster of serrations. Saurocythere

14’ Spermatic loop vertical; peniferum distal to dorsal margin of spermatic loop much less than twice as long as portion dorsal to loop; clasping apparatus with external border broadly serrate and terminating in annulations................ Okriocythere

15(13’) Anteroventral portion of peniferum with conspicuous anterodorsally directed projection............................ 22

15’ Anteroventral portion of peniferum never with conspicuous anterodorsally directed projection.............. Ankylocythere

16(12’) Posteroventral portion of peniferum with hook-like prominence................................................ 17

16’ Posteroventral portion of peniferum without hook-like prominence............................................. 18

17(16) Ventral portion of peniferum broadly flattened; posteroventral hook with associated spur............. Aurumcythere n. gen.

17’ Ventral portion of peniferum slender and bulbous; posteroventral hook without associated spur.............. Psittocythere

18(16’) Internal border of clasping apparatus usually with no more than three teeth; if more than three, with only two apical denticles or vertical ramus strongly convex posteriorly............................................................... 19

18’ Internal border of clasping apparatus usually with more than three teeth; apical cluster with more than two denticles, vertical ramus straight....................................................................................... 21

19(18) Clasping apparatus not clearly divisible into vertical and horizontal rami, extremities directed at an angle of at least 100 degrees............................................................................... Donnaldsoncythere

19’ Clasping apparatus usually divisible into vertical and horizontal rami, extremities directed at an angle no more than 90 degrees................................................................................................... 20

20(19’) Penis large, S-shaped or sinuous, and with curved posteroventral thickening of peniferum giving forcipate appearance to ven- tral portion of peniferum.................................................................. Thermastrocythere