Melaloncha gomezi, 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 : 51-52

Melaloncha gomezi new species

Fig. 41

Recognition. Females are recognized by the yellowish body color and the laterally flattened, setose ovipositor. The similar M. hirsuta might be just a variety of this species.

A single male specimen was collected in copula with a female, which allowed me to recognize further male specimens. In Borgmeier’s (1971b) key, this 2.1 mm long specimen has trouble passing couplet 9, where specimens are divided into species of medium size (2.5 mm) versus smaller species (1.8–2.0 mm). If one accepts that it is medium sized, it keys to M. genitalis Borgmeier , from which it differs by much less enlarged surstyli. If treated as a small species, it keys to M. pulchella , whose specimens are lost, whose identity is questionable, and whose female does not match that of M. gomezi .

Description. Female. Body length 1.6–2.1 mm. Frons yellow, bare of setulae except for few along eye margin; ocellar triangle black. Mean frontal width 0.45 head width, range 0.42–0.49. Medial furrow absent. Ocular setae black dorsally, brown laterally and ventrally; genal setae brown to black. Flagellomere 1 white basally, mostly yellow; aristomeres 1–2 yellow, 3 brown. Palpus white; palpal setae black. Scutum yellowishbrown with posterolateral dark brown spot. Scutellum yellow, with anterolateral dark round spot. Pleuron yellowish­brown except basalare black. Legs yellowish­brown. Combined length of foretarsomeres equal to length of foretibia. Foretarsal claws recurved, with large basal lobe. Mean costal length 0.48 wing length, range 0.46–0.51. Halter yellow. Abdominal tergites anteriorly yellow, posteriorly black. Venter of abdomen yellow. Ovipositor yellow at base, mostly dark brown to black; relatively straight (with only slight dorsal bend at basal one­third), laterally flattened; slightly differentiated into narrow dorsal and larger ventral lobe; with relatively long to short setae dorsally and ventrally.

Male. Frons yellow, bare of setulae except for few along eye margin; ocellar triangle black. Medial furrow absent. Postocular and genal setae brown to black. Flagellomere 1 basally white, apically yellow. Palpus white; palpal setae black. Scutum anteriorly yellowish­brown with large posteromedial dark brown spot occupying posterior one­third; some specimens with larger or smaller dark area, some as in female. Pleuron yellowishbrown, with sinuous, irregular, longitudinal dark brown stripe. Legs yellowish­brown, except apex of hind femur with dark brown spot. Abdominal tergites black, anteriorly with silver pollinosity. Venter of abdomen gray. Base of cercus dark brown, rest mostly yellow. Surstylus with setae of medium length.

Variation. The difference in ovipositor setal length among specimens is large, but most appear to belong to a single species. The three specimens from Argentina are especially divergent, in having few long dorsal setae, and the dorsal lobe of the ovipositor slightly longer than the ventral lobe.

Male specimens from La Selva Biological Station are darker than those from Las Cruces. There is more extensive brown color on the scutum, pleuron, and hind femur. The amount of scutal and pleural darkening varies widely, but the longitudinal line across the meron is almost always distinct.

Host. At Las Cruces we observed several individuals attacking workers of Oxytrigona mellicolor (Packard) on flowers of the exotic Brazilian palm Syagrus coronata . Flies were attracted to mixed aggregations of bees at other sites.

Geographical distribution. Costa Rica, Bolivia, Argentina.

Derivation of specific epithet. This species is named for Luis Diego Gómez, who kindly hosted our visit to Las Cruces.

Holotype. ♀, COSTA RICA: Puntarenas: Wilson Botanical Garden, Las Cruces , 8.79°N, 82.95°W, 13.vi.1998, B. Brown, V. Berezovskiy, flowers of Syagrus coronata (palm) [ LACM ENT 099084 ] ( LACM). A host bee specimen is mounted on a point on the same pin.

Paratypes. ARGENTINA: Misiones: Reserva Vida Silvestre Urugua­í , 25.97°S, 54.11°W , 1♀, 10.xii.2003, 1♀, 12.xii.2003, 1♀, 17.xii.2003, B. Brown, G. Kung, L. Gonzalez, honey spray, 400 m ( LACM, MACN) . BOLIVIA: La Paz: Coroico, Hotel Don Quixote , 16.19°S, 67.72°W, 1♀, 6.iv.2004, B. Brown, E. Zumbado, Phoenix palm flowers ( LACM) . COSTA RICA: Heredia: La Selva Biological Station , 10.43°N, 84.02°W, 1♀, ii.1980, W. Mason ( CNCI) , 1♀, ix.1992, P. Hanson, Malaise trap, 3♀, 15.ii–2.iii.1993, ALAS, Malaise trap M/05/20, M/08/023, M/07/022, 1♀, 15.iii.1993, ALAS, Malaise trap M/05/036, 1♀, 15.vii.1993, ALAS, Malaise trap M/01/152, 1♀, 15.iii.1994, ALAS, Malaise trap M/01/376, 1♀, 5.iii.1998, ALAS, light trap L/13/328, 1♀, 28.iv.1998, ALAS, light trap L/11/362, 2♀, 13.ii.2002, 1♂, 2♀, 15.ii.2002, 1♂, 5♀, 16.ii.2002, B. Brown, K. Walker, L. Gonzalez ( INBC, LACM, MCZC, MUCR, USNM) , 11 km SE La Virgen , 10.33°N, 84.07°W, 1♀, 8.iv.2003, ALAS, 05/M/20/080, 500 m ( LACM) ; Puntarenas: Wilson Botanical Garden, Las Cruces , 8.79°N, 82.95°W , 2♂, 1♀, 8.vi.1998, 6♂, 3♀, 12.vi.1998, 9♂, 5♀ (including one in copula pair), 13.vi.1998, 4♂, 1♀, 14.vi.1998, 1♂, 1♀, 16.vi.1998, B. Brown, V. Berezovskiy, flowers of Syagrus coronata (palm) ( INBC, LACM) .

Figures

FIGURES 32–42. Melaloncha spp., female, ovipositor, left lateral (except Fig. 40, bottom). Figures. 39 and 40 showing intersegmental membrane and sclerite of intersegment 7–8.