Efferia nigrimystacea (Macquart, 1845)

Smit, John T., 2019, Robber flies from Sint Eustatius, Lesser Antilles, with the descriptions of Efferia exaggerata sp. n. and the male of Ommatius prolongatus Scarbrough (Diptera: Asilidae), Zootaxa 4586 (1), pp. 141-150 : 145

Efferia nigrimystacea (Macquart, 1845)

( Fig. 4 )

Erax nigrimystaceus Macquart, 1847: 57 . Walker 1855: 633; Aldrich 1905: 277.

Asilus nigrimystaceus, Hull 1962: 546 .

Eicherax nigrimystaceus, Martin & Papavero 1970: 70 .

Efferia nigrimystacea, Scarbrough & Knutson 1989: 519 –537; Scarbrough and Perez-Gelabert, 2009: 52 ; Papavero 2009: 18.

Specimens examined. 5♂ 7♀, De Boven, 6.x.2015, 12.x.2015; 1♀, De Boven, plot H1, 6.x.2015; 1♀, White Wall, plot M8, 14.x.2015.

Diagnosis. The males can easily be recognized by the dense, long black hairs, apically on sternite 8, whereas the gonocoxa has only a few scattered long hairs ventrally. The epandrium is rather rectangular and blunt apically, with a square notch apico-dorsally and a rounded notch apico-ventrally, with some short and stout setae in the apicoventral corner. Females have the palpi with black setae, the post pronotum and postalar callus black, not reddish and the mystax with predominatly black bristles, tergites 2–6 dark with posterior margins lighter grey dusted.

Distribution. This was thus far the only Efferia species known from the Lesser Antilles, described from Guadeloupe and recorded from Barbuda, Dominica, Montserat, St. Lucia, Redonda & St. Vincent ( Scarbrough & Perez-Gelabert, 2009). The discovery of E. nigrimystacea on St. Eustatius means that it is probably more widely distributed in the northern part of the Lesser Antilles.

Figures

FIGURE 4. Efferia nigrimystacea (Macquart). A: male lateral view. B: female lateral view. C: right wing of male.