Pselaphaulax, Reitter, 1909

Owens, Brittany E. & Carlton, Christopher E., 2022, Revision of the New Zealand species of the Genus Pselaphaulax Reitter (Staphylinidae: Pselaphinae: Pselaphitae: Pselaphini), Zootaxa 5155 (2), pp. 221-244 : 225-226

Key to the New Zealand species of Pselaphaulax (males)

Extensive examination of NZ Pselaphaulax specimens by the first author has yielded very few external morphological characters useful for species-level identification. As a result, this key relies heavily on characters of the male genitalia. In most cases, identification of females is only possible via association with male specimens.

1 Gular mound ovate, narrowed posteriorly and anteriorly (except P. meliusculus ); pronotum with median antebasal fovea welldeveloped with lateral carinate ridges; mesoventral shield with setose fovea present.................. 2 (species group 1)

1’ Gular mound rounded, wider anteriorly, narrowed posteriorly; pronotum with median antebasal fovea reduced or pit-like; mesoventral shield unmodified, setose fovea absent (except P. dracophyllum )...................... 7 (species group 2)

1” Possessing a combination of characters of both species groups: gular mound rounded posteriorly (group 2); pronotum with median antebasal foveae well-developed, mesoventral shield with setose foveae (group 1).................................................................................... Pselaphaulax intermedius Owens & Carlton , sp. nov.

2(1) Gular mound broad anteriorly and narrowed posteriorly, not ovate........................ P. meliusculus (Broun) , 1893

2’ Gular mound narrowed anteriorly and posteriorly, ovate....................................................... 3

3(2’) Ventral process of aedeagus not distally curved downwards; reduced or blunt at apex................................ 4

3’ Ventral process of aedeagus curved downwards, distally; apex acute, narrow...................................... 5

4(3) Ventral process of aedeagus reduced, shortened, apically blunt; fleshy process associated with narrow median lobe........................................................................................ P. pilifrons (Broun) , 1914

4’ Ventral process of aedeagus reduced, apparently absent; median lobe broad........ P. ramsayi Owens & Carlton , sp. nov.

5(3’) Ventral process of aedeagus serrate; dorsal processes associated with median lobe elongate, narrow, not noticeably curved........................................................................ P. pelorus Owens & Carlton , sp. nov.

5’ Ventral process of aedeagus smooth; median lobe distinctly curved.............................................. 6

6(5’) Median lobe of aedeagus and associated left lateral process both curved towards the right.............................................................................................. P. hornabrooki Owens & Carlton , sp. nov.

6’ Median lobe of aedeagus lacking associated left lateral process curved towards the right................................................................................................... P. tararua Owens & Carlton , sp. nov.

7(1’) Mesoventral shield modified, setose fovea present posterior to procoxae................................................................................................... P. dracophyllum Owens et al. (Subantarctic Islands)

7’ Mesoventral shield unmodified, setose fovea absent.......................................................... 8

8(7’) Males with ventrite II with large, deep, oval depression extending length of ventrite... P. nunni Owens & Carlton , sp. nov.

8’ Males with ventrite II not with large, deep, oval depression, median area slightly flattened or otherwise modified......... 9

9(8’) Ventrite II with two patches of setae on apex, distribution restricted to Chatham Is... P. caeruleus Owens et al. (Chathams)

9’ Ventrite II nude, not with two patches of setae on apex....................................................... 10

10(9’) Parameres of genitalia reduced and shortened, no more than ½ length of median lobe, distribution restricted to Chatham Is......................................................................... P. traversi Owens et al. (Chathams)

10’ Parameres of genitalia not visibly shortened, longer than ½ length of median lobe................................. 11

11(9’) Ventral process of aedeagus associated with accessory serrate process, at least in part............ P. pauper (Sharp) , 1874

11’ Ventral process of aedeagus not associated with accessory serrate process........................................ 12

12 Aedeagus with distal end of median lobe not curved to right, dorsal process poorly developed; distribution restricted to Chatham Is...................................................................... P. flavus Owens et al. (Chathams)

12’ Aedeagus with distal end of median lobe curved to right, dorsal process well-developed and extended over median lobe before projecting ventrally............................................................. P. meliusculus (Broun) , 1893