Melaloncha digitalis Borgmeier, 1959

Brown, Brian V., 2006, Revision of the untreated taxa of Melaloncha s. s. bee-killing flies (Diptera: Phoridae), Zootaxa 1280 (1), pp. 1-68 : 17-18

Melaloncha digitalis Borgmeier

Figs. 5 , 56

Melaloncha digitalis Borgmeier, 1959, p. 176 , figs. 63–66, 75 (♂, ♀; Nova Teutônia, Santa Catarina (type locality); Sepetiba , Rio de Janeiro).

Recognition. The type series of this species consists of several specimens that were preserved for decades in alcohol; thus, they have lost nearly all their original coloring and have faded to a uniform brown. Based on the original description by Borgmeier, however, there are sufficient details to characterize these types as conspecific with a darkly­colored form of widespread distribution. The species within the M. digitalis group are extremely uniform, however, and further study might uncover cryptic species within the current concept of M. digitalis .

Males are distinguished from those of M. immaculata by the darkly­colored and longsetose cercus. They key out correctly in the latest key to male Melaloncha ( Borgmeier 1971b) .

Description (based largely on newly collected material). Female. Body length 1.5–2.5 mm. Frons mostly dark brown, orange on ventral one­fifth and dorsolateral corners; bare of setulae. Mean frontal width 0.46 head width, range 0.43–0.50. Ocular and genal setae black. Flagellomere 1 orange­brown to yellow, dark brown on flattened dorsal surface; arista black. Palpus yellow to orange­brown; palpal setulae black, extremely short and fine. Scutum and scutellum dark brown. Pleuron dark brown, anterodorsally light brown in some specimens; all except katepisternum with silver pollinosity. Legs yellowish­brown, except mid­ and hind coxa dark brown (forecoxa also dark brown in some specimens); apex of hind femur with dark brown spot. Combined length of foretarsomeres equal in length or slightly longer than tibia; foretarsomeres elongate, slender. Foretarsal claws simple, unmodified, without basal lobe. Mean costal length 0.55 wing length, range 0.53–0.57. Halter yellow. Abdominal tergites black to brown, with silver pollinosity. Medial fingerlike eversible gland present posterior to tergite 6. Venter of abdomen dark gray. Ovipositor black, with various amounts of light brown color near apex; tube­shaped, dorsally curved; densely setose (similar to that of M. immaculata , Fig. 7 ).

Male. Frons mostly dark brown, orange on ventral one­fifth and dorsolateral corners; bare of setulae. Flagellomere 1 yellow, with small amount of dark color 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 dark brown spot; mid­ and hind coxae also dark brown. Abdominal tergites black with silver pollinosity. Venter of abdomen dark gray. Cercus dark brown with unusually long setae. Epandrium with long setae.

Host. Some specimens were collected associated with the bee Partamona musarum (Cockerell) . The bee nest was apparently in the ground, with its opening in the sand on one side of an active Atta sp. leaf­cutter ant nest. Male flies congregated near the nest opening, standing on the soil.

Geographical distribution. Brazil to Costa Rica.

Other material examined. BRAZIL: Rio de Janeiro: Ilha de Guaiba , Baia de Sepetiba , 1♂, 15.x.1953, L. de Oliveira ( MZSP) ; Rondonia: 62km SE Ariquemes , 1♂, 17–24.iii.1989, 1♂, 15–22.iii.1991, 1♀, 7–18.xi.1995, 1♂, 1♀, 5–16.xi.1996, 1♀, 22–31.x.1997, W. J. Hanson ( EMUS, LACM) ; Santa Catarina: Nova Teutônia , 2♂, 1♀, same data as holotype ( MZSP) . COLOMBIA: Amazonas: Amacayacu National Park , 3.82°S, 70.26°W, 1♂, 3♀, 4.ix.1997, 1♂, 5.ix.1997, B. Brown, G. Kung, nest of Partamona musarum (LACM) , 1♂, 8–9.iii.2000, B. Brown, G. Kung, M. Sharkey, Malaise trap #4 ( LACM) , 2♀, 12–20.iii.2000, A. Feliz, Malaise trap #1, #2 ( LACM) , 1♀, 30.vii–8.viii.2000, B. Amado, Malaise trap, CAP­836 ( UNCB) ; Caquetá: PNN Chiribiquete, Rio Cuñare , 0.53°N, 72.63°W, 2♀, 15–19.xi.2000, E. Gonzalez, M. Ospina, Malaise trap, CAP­957 ( LACM, UNCB) . COSTA RICA: Alajuela: 20 km S Upala , 1♀, 21–30.iv.1991, F. D. Parker ( LACM) ; Guanacaste: Los Almendros, PN Guanacaste, 1♂, 28.iii–24.iv.1992, G. Gallardo ( INBC) , 3 km SE Rio Naranjo , 1♀, 14–20.viii.1993, F. D. Parker ( EMUS) ; Heredia: Chilamate , 2♂, 24–30.vii.1993, S. Keller ( EMUS, LACM) , La Selva Biological Station , 10.43°N, 84.02°W, 1♀, 1.iv.1996, ALAS, Malaise trap M/04/618 ( INBC) ; Puntarenas: 24 km W Pan American Hwy [= 24km W Piedras Blancas ], 1♀, iii–iv.1989, Malaise trap, P. Hanson, I. Gauld ( LACM) ; San José: Zona Protectora El Rodeo , 9.91°N, 84.28°W, 2♂, 1–5.viii.2001, B. Brown, V. Berezovskiy, G. Kung, Malaise trap ( LACM) . MEXICO: Tamaulipas: Highway 70, km 87, 50 mi E Ciudad Victoria , 1♂, 21.ii.1986, R. W. Jones ( TAMU) . PANAMA: Fort Gulick, Quarters 40­A, 1♀, v.1986, H. J. Harlan, at light ( USNM) . PERU: Madre de Dios: Pakitza , 11.94°S, 71.28°W, 7♂, 19.ii.1992, B. Brown, D. Feener, stingless bee nest entrance ( LACM, MUSM) ; San Martin: San Antonio de Cumbaza , 6.40°S, 76.41°W, 1♂, 9.vii.2004, B. Brown, E. Corona, honey­spray, 400 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.

FIGURES 56–61. Melaloncha spp., female, scanning electron micrographs. 56–57. Foretarsal claws. 56. M. digitalis, 57. M. palpalis. 58–60. Venter of forefemur. 58. M. lacerna, 59. M. laselvae, 60. M. zurquiensis. 61. Intersegment 7–8, M. gradata.