Pachycerina atrimela, Davies & Miller, 2009

Davies, Gregory B. P. & Miller, Raymond M., 2009, Revision of Afrotropical Pachycerina Macquart (Diptera: Lauxaniidae), African Invertebrates 50 (2), pp. 295-295 : 307-308

Pachycerina atrimela sp. n.

Figs 19 , 31 , 42

Etymology: From Latin ater (black) and melos (limb), in reference to the black legs of this species (including coxae, trochanters and femora).

Diagnosis: P. atrimela is characteristed by the following distinctive traits: (a) black legs (the coxa, trochanter and femur of all the legs are black or dark brown), (b) having the sternopleuron and meropleuron completely black or dark brown, and (c) the abdomen completely black. The combination of black legs, lower thorax and abdomen gives the species a distinctive swarthy aspect that can be noticed with the naked eye. The shape of the male S5 is also diagnostic ( Fig. 42 ), lacking the medial spur and having the posterior processes short and medially extended for a short distance. When cleared in KOH, no paired spots can be seen in the darkened cuticle of T6.

Description:

Head: Fronto-orbital plate from posterior fronto-orbital bristle to inner vertical seta brown. Prefrontal spots large and black and touching sides of prefrons laterally. Scape and pedicel brown (lightly infuscated), postpedicel yellow.

Thorax: Striping pattern on scutum indistinct, dorsum largely orange-brown with thin, medial vitta of yellow, edges of scutum yellow. Scutellum yellow, no infuscation. Upper lateral thoracic vitta from humeral callus to pteropleuron. Lower lateral thoracic vitta expanding to cover all of sternopleuron and meropleuron. Postscutellum and postnotum blackish brown. All legs black or dark brown, except meso- and metatibia and meso- and metatarsus yellow-brown. Wing hyaline. Haltere basally yellow, distally black.

Abdomen: Black.

Male terminalia ( Figs 19 , 31 , 42 ): S5 posterior processes not elongate but medially expanded, no medial spur. No T6 spots. Surstyli short (shorter in length than epandrium). Gonopods strongly asymmetric, right gonopod long with hooked apex and tiny lateral spinule (not shown in illustration), left gonopod short with lateral spinule. Aedeagal apodeme rounded anteriorly and tapering posteriorly.

Measurements: ơ (n=2), ^(n=4): head length – ơ 0.8, ^0.7; thorax length (incl. scutellum) – ơ 1.9, ^1.9; abdomen length – ơ 1.7, ^1.8; wing length – ơ 3.9, ^3.8. Holotype: ơ MADAGASCAR: Andasibe (= Périnet) [18°49'S: 43°26'E], 6.x.1958, F. Keiser (MHNB).

Other material examined: MADAGASCAR: 3ơ 2^Andasibe (= Périnet) [18°49'S: 43°26'E], 12.x.1970, P. Hammond ( BMNH) ; 2ơ 2^same locality, 9.iv.1958, F. Keiser ( MHNB) ; 6ơ 4^same locality, 21.ix– 6.x.1958, F. Keiser ( MHNB) ; 5ơ 3^same locality, xii.1955, B.R. Stuckenberg ( NMSA) ; 2ơ 2^Montagne d’Ambre [12°32'S: 49°10'E], 16.x.1970, P. Hammond ( BMNH) ; 1^near Anjiro , 21.x.1970, P. Hammond ( BMNH) ; 3ơ 12^Mandraka [18°55'S: 47°55'E], 4.iv.1958, F. Keiser ( MHNB) ; 1ơ Mananjary [21°17'S: 47°56'E], 20.viii.1958, F. Keiser ( MHNB) .

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 28–33. Dorsal view of male inner genitalia: (28) Pachycerina obscuripennis Lamb; (29) Pachycerina potentilla sp. n.; (30) Pachycerina stuckenbergi sp. n.; (31) Pachycerina atrimela sp. n.; (32) Pachycerina gabela sp. n.; (33) Pachycerina pellocera sp. n. Abbreviation: aed apo – aedeagal apodeme. 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.