Dacus (Psilodacus) goergeni, Meyer & White, 2013

Meyer, Marc De, White, Ian M. & F. M. Goodger, Kim, 2013, Notes on the frugivorous fruit fly (Diptera: Tephritidae) fauna of western Africa, with description of a new Dacus species, European Journal of Taxonomy 50, pp. 1-17 : 10-12

Dacus (Psilodacus) goergeni sp. nov.

urn:lsid:zoobank.org:act:47F1AD2E-9183-4C0F-A65B-D9FDBB15DB1D

Fig. 4

Etymology

Named in honour of the collector, Dr Georg Goergen, who is also the founder and conservator of the entomological collections at the International Institute of Agriculture.

Material

Holotype

♂, TOGO, Kloto , Jan. 2006, ‘ on Solanum sp.’, leg. G. Goergen (deposited in collection of IITA).

Paratypes

TOGO: same locality as holotype, 1 ♂, Dec. 2005, ‘on Acacia auriculiformis ’; 2 ♂♂, 5 ♀♀, Jan. 2006; 1 ♂, 3 ♀♀, Jan. 2006, ‘on Solanum sp.’; 4 ♂♂, 1 ♀, Jan. 2008; 1 ♂, 1 ♀, Feb. 2008. BENIN: Lokossa, 1 ♂, 1 ♀, Jan. 2006. All leg. G. Goergen. Paratypes deposited in collections of IITA, NHM and RMCA.

Description

SIZE. 6.2-7.5 mm, wing length 4.8-6.6 mm.

HEAD. Pedicel and 1st flagellomere not longer than ptilinal suture. Face ( Fig. 4A ): antennal furrow without a dark spot; upper area with a dark marking, tending to an inverted V-shaped dark marking (in some specimens this extends down each side of carina and may be mistaken for facial spots). Frons: frontal setae 0, orbital seta 0.

THORAX. Scutum ( Fig. 4B ) predominantly fuscous, tending to red-brown antero-laterally; postpronotal lobe entirely pale, yellowish; notopleural callus pale posteriorly, anteriorly concolorous with scutum; notopleural xanthine probably isolated from notopleural callus but can appear almost joined (as in wedge form); lateral and medial postsutural vitta absent. Scutellum without any dark patterning (except for basal dark margin, which is very narrow). Anepisternum ( Fig. 4C ) with a stripe from notopleural callus to (or almost to) katepisternum; stripe very broad (anteriorly extending almost to postpronotal lobe); extended onto katepisternum. Laterotergal xanthine confined to katatergite.

THORACIC SETAE. Anterior notopleural seta present; anterior supra-alar seta present.

WING ( Fig. 4E ). Basal cell bc without microtrichia; cell c with an almost complete (> 90%) covering of microtrichia; cell bm without microtrichia. Narrow subbasal raised section of cell br with extensive covering of microtrichia; partly bare in apical half. Crossvein R-M beyond middle of cell dm. Costal band complete; shallow, not or barely extending below vein R 2+3, except in basal section (before crossvein R-M) and at wing apex; expanded into a small spot at apex. Anal streak absent (but with a trace of colour confined to cell bcu). Cells bc and c coloured (not as deep as costal band). Without any crossbanding.

LEGS. Forefemur pale, yellowish, sometimes indistinctly darkened apically; midfemur bicoloured (pale basal half to two-thirds, red-brown apically); hindfemur pale, yellow, rarely distinctly darkened apically.

ABDOMEN. Predominantly fuscous; shape and patterning, see Fig. 4D . Tergites I-V all fused.

Male

Tergite III with some very fine hairs (possible vestigial pecten); lacking hindtibia preapical “pad”. Basal costal sections without specialised setae.

Female

Aculeus pointed, similar to B. stylifer .

Host

No host records known (some material is indicated as being found on Solanum sp. or Acacia auriculiformis but there is no indication that either of these plants is a host).

Distribution

Reported from Benin and Togo.

Remarks

The new species is very similar to Dacus stylifer which is an East African species. It differs in the wing cell c having almost complete coverage of microtrichia in the males (50% in male stylifer ); the midfemur bicoloured (pale in typical stylifer ); the notopleuron bicoloured and sutural xanthine distinct, unlike typical stylifer . Dacus goergeni sp. nov. is placed in the ill-defined subgenus Psilodacus , based upon a combination of characters, which typify the grouping, including the lack of facial spots: the dark, almost inverted V-shaped, dark marking at the top of the face; lack of anal streak and male pectin; it differs from most Psilodacus spp. in having anterior supra-alar setae. The type specimens were captured in the Guinean Forest Savannah Mosaic and the Eastern Guinean Forest ecoregions. Label information indicates that the specimens were collected in forested areas.

Figures

Fig. 4. Dacus goergeni sp. nov. A. Head, frontal view. B. Thorax, dorsal view. C. Thorax, lateral view. D. Abdomen, dorsal view. E. Wing.