Pachycerina seychellensis Lamb, 1912

Davies, Gregory B. P. & Miller, Raymond M., 2009, Revision of Afrotropical Pachycerina Macquart (Diptera: Lauxaniidae), African Invertebrates 50 (2), pp. 295-295 : 316-317

Pachycerina seychellensis Lamb, 1912

Figs 21 , 38 , 47

Pachycerina seychellensis: Lamb 1912: 307 . Type locality: Seychelles (Silhouette & Mahé) .

Lamb’s description is good, and allows confident recognition of P. seychellensis . The pin bearing the ‘type’ label has two specimens mounted on cork, a male and a female. General coloration and chaetation of P. seychellensis is as per the genus (i.e. Afrotropical species). Several specimens from Silhouette Island and one specimen from Mahé Island show an interesting feature in having milky white stigmata; the stigma is usually transparent. In his description, Lamb (1912) did not describe a whitened stigma from P. seychellensis . Other notable features are: (a) blackish protibia with apical collar of yellow, (b) profemur posteriorly yellow, but with brown area apically, (c) poorly defined fronto-orbital plates (faintly coloured), and (d) brownish smudge in lower lateral corner of prefrons (face).

Male terminalia ( Figs 21 , 38 , 47 ): Surstyli slightly longer than epandrium. T6 spots present. Gonopods asymmetric, right gonopod longer than left gonopod. Both gonopods with lateral spinules (not illustrated on right gonopod). Aedeagal apodeme short and rotund. S5 with straight posterior processes and medial spur.

Simmonds (1969: 26) listed the species without comment from Principé Island in the Gulf of Guinea, West Africa.The identification as P. seychellensis is highly questionable. Syntypes (examined): ơ ^SEYCHELLES: Silhouette, 1908, J.S.Gardiner ( BMNH) .

Other material examined: SEYCHELLES: 7ơ 10^Mahé , La Misere, 18–19.viii.1976, light trap, I.H. & J.B. Haines ( NMSA) ; 1ơ Mahé, Morne Séychellois [04°38'S: 55°26'E], 13–17.vii.1972, P.L.G. Benoit & J.J. van Mol ( MRAC) ; 3^Silhouette, Mare Cochons , 2–8.vii.1972, P.L.G. Benoit & J.J. van Mol ( MRAC) ; 1^Mahé , Beau Vallon [04°36'S: 55°25'E], 20–24.iv.1965, Tams & Nye ( BMNH) .

Figures

Figs 17–22. Posterior view of male terminalia: (17) Pachycerina potentilla sp. n.; (18) Pachycerina pellocera sp. n.; (19) Pachycerina atrimela sp. n.; (20) Pachycerina obscuripennis Lamb; (21) Pachycerina seychellensis Lamb; (22) Pachycerina nigrivittata sp. n.Abbreviations: pro – protandrium, epa – epandrium, sur – surstylus. Scale bar = 0.8 mm.

Figs 34–38. Dorsal view of male inner genitalia: (34) Pachycerina nigrivittata sp. n.; (35) Pachycerina vaga Adams; (36) Pachycerina crinicornis (Thomson); (37) Pachycerina micropunctata sp. n.; (38) Pachycerina seychellensis Lamb. Scale bar = 0.5 mm.

Figs 39–48. Sternite 5 of male Pachycerina species: (39) P. vaga Adams; (40) P. nigrivittata sp. n.; (41) P. gabela sp. n.; (42) P. atrimela sp. n.; (43) P. pellocera sp. n.; (44) P. stuckenbergi sp. n.; (45) P. crinicornis (Thomson); (46) P. potentilla sp. n.; (47) P.seychellensis Lamb; (48) P. micropunctata sp. n. Abbreviation: post proc – posterior process. Scale bar = 0.5 mm.