Melaloncha immaculata, Brown, 2006

Brown, Brian V., 2006, Revision of the untreated taxa of Melaloncha s. s. bee-killing flies (Diptera: Phoridae), Zootaxa 1280 (1), pp. 1-68 : 19-21

Melaloncha immaculata new species

Fig. 7

Recognition. This species is extremely similar to M. digitalis , differing by the lack of a spot at the apex of hind femur in females, and the light brown, less setose cercus in males. The higher elevation habitat and different host are further indications that it probably is a separate species. This pattern of similar species in a lowland and middle elevation site is repeated below, with M. laselvae and M. zurquiensis .

Description. Female. Body length 2.4–3.0 mm. Frons mostly dark brown, orange on ventral one­fifth, lateral borders, and dorsolateral corners; with scattered, sparse setulae close to eye margin. Mean frontal width 0.45 head width, range 0.43–0.48. Ventral frontoorbital setae more medial than in M. digitalis . Ocular and genal setae black. Flagellomere 1 orange­brown, dark brown dorsally and on apical one­third; arista black. Palpus orangebrown; palpal setulae black, short and fine. Scutum, scutellum and pleuron dark brown; all of pleuron except katepisternum covered with silver pollinosity. Legs yellowish brown, except forecoxa light brown, mid­ and hind coxa dark brown, basal one­third of foretibia dark brown, and apex of hind femur light brown, slightly darker than rest of femur. Combined length of foretarsomeres approximately 1.2 times length of foretibia. Foretarsal claws simple, unmodified, without basal lobe. Mean costal length 0.52 wing length, range 0.50–0.55. Halter yellow to white. Abdominal tergites dark brown with silver pollinosity. Venter of abdomen dark gray. Ovipositor black, with small amount of light brown color near apex; tube­shaped, dorsally curved; densely setose.

Male. Frons mostly dark brown, orange on ventral one­fifth, lateral borders, and dorsolateral corners; with scattered, sparse setulae close to eye margin. Flagellomere 1 orange, except dark brown dorsally and at apex; arista black. Palpus white to yellow; palpal setulae black, extremely short and fine. Postocular and genal setae black. Scutum and pleuron dark brown; all of pleuron except katepisternum covered with silver pollinosity. Legs yellowish brown, except apex of hind femur with large light to dark brown spot; base of foretibia, all of mid­ and hind coxae also dark brown. Abdominal tergites black with silver pollinosity. Venter of abdomen dark gray. Cercus light brown with shorter setae than M. digitalis . Epandrium with long setae.

Host. I collected several specimens at the entrance of a nest of Trigona fulviventris Guérin , the same nest where I observed attacks on these bees by another phorid, Apocephalus altapivorus Brown ( Brown 1996) .

Geographical distribution. Costa Rica, Guatemala.

Derivation of specific epithet. Latin, “immaculate”, referring to the lack of a dark spot at the apex of the hind femur in female specimens.

Holotype. ♀, COSTA RICA: Puntarenas: Las Alturas , 8.95°N, 82.83°W, 10–13.vi.1998, B. Brown, V. Berezovskiy, Malaise trap #1, 1600 m [ LACM ENT 133008 ] ( LACM).

Paratypes. COSTA RICA: Puntarenas: Las Alturas , 8.95°N, 82.83°W, 1♂, 2♀, x.1991, 1♀, xi.1991, P. Hanson, Malaise trap ( LACM, MUCR) , 1♂, 9.vi.1998, B. Brown, V. Berezovskiy, Malaise trap #1, 1600 m ( LACM) , Las Alturas, Echandi Trail #20, 2♂, 12.viii.1995, 1♂, 2♀, 15.viii.1995, 1♂, 16.viii.1995, B. Brown, attacking workers of Trigona fulviventris (LACM) , Las Cruces, 8.8°N, 82.97°W, 1♀, 16.v.2000, G. Kung, on Syagrus coronata flowers, 1♀, 17.v.2000, G. Kung, at honey on cards [bait for host bees] ( LACM) . GUATEMALA: Zacapa, near La Trinidad, 15.05°N, 89.94°W, 27.v.1997, M. Metz, aspirated from stingless bee nest, 1600 m ( LACM) .

Figures

FIGURES 5–8. Melaloncha spp., female. Figs. 5–6. Head, anterior. Figs. 7–8. Ovipositor, left lateral. Abbreviations: vfo—ventral fronto­orbital seta, vif—ventral interfrontal seta.