Pachylophus obscurior Becker, 1916

Deeming, John C., 2018, A revision of the Afrotropical species of Pachylophus Loew (Diptera: Chloropidae) and some related Ovoviviparous genera, Zootaxa 4482 (1), pp. 1-51 : 17-19

Pachylophus obscurior Becker, 1916

( Plate 13 , Figs 64, 65)

Pachylophus pellucidus var. obscurior Becker, 1916: 425

Pachylophus lituraticrus Lamb, 1917: 37

Described as a variety of pellucidus from South Africa, and further recorded from Kenya, Uganda, Burundi, Rwanda, Lesotho and Nigeria.

Material: 1♀, N. NIGERIA: near. Kafanchan, Kagoro Forest , 15.x.1979, J.C. Deeming ; 1♀, GHANA: Western Region, near Takoradi, Agona Junction, 8.xi.1995, M.R. Wilson ; 1♂, CAMEROUN: Yaoundé, Bastos, 11.ix.1977, R. Baker ; 1♀, Nkoemvon , 12.vii.1978, D. Jackson (all in NMWC) ; 3♀, Victoria, 1939, P. Lepesme, R. Paulian & A. Villiers ; 2♂, Batouri, no further data; 1♂, Akonolinga, no further data (all in MNHN); 1♂, LIBERIA: 20 km E. of Monrovia, W. A.R.D . A. Fendall Training Centre , 16.i.1982, P.C. Matteson ( NMWC) ; 1♂ 3♀, KENYA: Bungoma, 6–7.xi.1983 , A. Freidberg ( TAU); 1♂ , Kisumu, 17.xii.1970 , A.E. Stubbs ( NHMUK) ; 1♂ 2♀, UGANDA: Serere, 26.i.1973, J.L. Overman ( NMWC) ; 1♂ 2♀, CENTRAL AFRICAN REPUBLIC: W. bank of River Oubangui N. of its confluence with the Lobaye, Zinga , 9.iv.1983, M. v. Tschirnhaus (X883), ( ZSM) ; 7♂ 1♀, ANGOLA: Salazar , sweeping flowering grasses, 11.iii.1972, BMSAE ( NHMUK) .

A dissected female from Serere was found to contain a large larva with cephaloskeleton and segmentation visible.

Pachylophus pellucidus Becker, 1910: 393

Described from Kenya and Tanzania.

Material: 4♀, YEMEN: Al Khowd , Malaise trap, iv.1993, A. van Harten ; 2♀, Al Khowd , light trap, iv.2000, A. van Harten & S. Al Haruri ; 1♀ environs of Zinjibar , 21.iii.1993, A. van Harten ; 1♂ 2♀, Lahj , 17.v. –15.vi.2000, Malaise trap, A. van Harten & A. Sallam ; 1♂ 2♀, same data but vii.2000 ; 1♂ 3♀ same data but 4.v.2001, A. van Harten (all in NMWC) ; 1♀, ETHIOPIA: Shewa Distr., River Awash Wenz S. of Nazret, 15.iii.1995, M. v. Tschirnhaus , (X1015), ( ZSM) ; 1♀, with puparium KENYA: just S. of Archer's Post, coll. as larva ex terminal shoot of Sporobolus sp. (grass sample in NHMUK coll. Mrs. M.E. Nye ref. L39) 11.vi.1956, adult em . 30.vi., I.W.B. Nye; 1♀, with puparium same data ; 1♂, same data but 29.viii.1956 ; 1♂ 1♀, same data but 9.viii.1956 (all in NHMUK).

The puparium of the first listed specimen from Kenya is that referred to ( Deeming 1985: 407) in a comparison of immature stages, and it is from this that the description given here is made. Of the above material the specimens vary in size, those from Yemen having a wing length of from 2.25–3.7mm, those from Kenya 4.1mm, and that from Ethiopia 3.3mm. I strongly suspect that this can be attributed to those smaller specimens developing in a different hostplant, which did not provide sufficient larval food for growth to optimum size. Dr. Ebejer kindly compared one of the above-listed females from Al Khowd with the type series and found it to compare well apart from an antennal character, which he reports as "The third segment, particularly the part over-ridden by the second, is clearly narrower than in the types (same sexes compared)." Here again the difference might be explained by smaller size or be due to the Al Khowd material originally having been preserved in alcohol and some distortion resulting in the process of drying. A female from Al Khowd was found to contain a single large egg.

Puparium 6.2mm in length, 1.5mm in greatest breadth, subshining, yellowish brown, tubular; mandibular sclerite ( Plate 5 , Fig. 21); anterior spiracles ( Plate 1 , Fig. 2) transversely orientated and situated on upper puparial emergence cap; posterior spiracles ( Plate 1 , Fig. 3) black, with the usual 3 respiratory slits on a slightly raised base.

Figures

PLATE 1. Figs 1–3, Pachylophus pellucidus Becker; 1, female, habitus; 2, puparium, anterior spiracle; 3, puparium, posterior spiracles.

PLATE 5. Figs 21–25, Pachylophus spp. larval mandibular sclerites; 21, P. pellucidus Becker; 22, P. femoratus (Johnson); 23, P. flavipes Lamb; 24, P. nigeriensis sp. n.; 25, P. varipes Adams. Pachylophus pellucidus Becker, 1910 (Plate 1, Figs 1–3; plate 5, Fig. 21; plate 10, Figs 47–49)

PLATE 13. Figs 62–67. Pachylophus spp. 62, P. ismayi sp. n., frons; 63, same, habitus; 64, P. obscurior Becker, frons; 65, same, habitus; 66, P. rufescens (de Meijere), frons; 67, same, habitus.