Eudexia formidabilis ( Bigot, 1889 )

Santis, Marcelo Domingos De, 2021, The Neotropical genus Eudexia Brauer & Bergenstamm, 1889 (Tachinidae: Dexiinae: Dexiini): lectotype fixation for the type species, synonymy and a new species from Brazil, Zootaxa 5004 (4), pp. 538-550 : 541-543

Eudexia formidabilis ( Bigot, 1889)

( Fig. 1 )

Rhamphinina formidabilis Bigot, 1889: 264 ; Wulp (1891: 225; discussion of placement in the genus Hystrichodexia ).

Eudexia formidabilis ( Bigot, 1889) : Brauer & Bergenstamm (1889: 94; discussion of Eudexia goliath as synonymous with Rhamphinina formidabilis ); Aldrich (1924: 213; notes on type of E. goliath ); Townsend (1931: 101; notes on type, synonymy with E. goliath , new combination); Guimarães (1971: 29; catalog); Nihei (2016: 909 , inferred distribution, catalog of Colombian Tachinidae ); O’Hara et al. (2020: 49; checklist of World Tachinidae ).

Note. The mention by Townsend (1938: 334) of a “Ht male” (in NHMUK) is not regarded as a lectotype fixation, because the specimen in question cannot be distinguished among the three male syntypes present in NHMUK. Therefore, a lectotype is designated herein .

Type material examined. Lectotype male, by present designation, deposited at NHMUK and labeled as follows ( Fig. 1B ): “ Syntype ” “ Rhamphinina fomidabilis/Cotype”; “ Mexico / Ex coll. Bigot. / Press by G.H. Verral,/ Oct. 1904 / 1904-274”; “BMNH (E) #/ 230935”; “ Lectotype ” [red label]; “NHMUK013933558”. [Specimen in good condition, but right postpedicel missing.]

Paralectotypes: 2 ♂♂, same locality and data as lectotype; ‘Paralectotype’ [green label]. Conspecific with the lectotype .

Diagnosis. Head with prementum short, about 0.5 x length of head. Postpedicel dark brown, but proximal 1/5 light yellow. Fronto-orbital plate with setulae throughout its length, terminating at the base of the postpedicel. Upper and lower calypters dark brown. Abdomen yellow with a continuous dorsal brownish black median vitta interrupted from syntergite 1+2 to tergite 4, without pruinosity on tergites 3 to 5.

Redescription. Male. Body length: 13.4 mm.

Coloration ( Fig. 1A, C ). Occiput whitish. Head with dark silver pruinosity, but genal dilation with brownish pruinosity. Scape light brown and pedicel dark brown. Postpedicel dark brown, but about proximal 1/4 light yellow. Arista dark brown, but proximal 1/5 light brown. Palpus light yellow. Labellum light brown, prementum shiny black. Scutum brownish-black, but presutural region and anterodorsal portion of postsutural region with silver pruinosity, fading to brownish-black posteriorly; presutural region with five brownish-black vittae, the three central ones narrow and the two peripheral ones broad. Scutellum light brown. Wing hyaline, but darkened in proximal area and along the veins. Tegula light brown, basicosta yellow. Halter yellowish-brown. Posterior spiracle yellowishbrown. Legs brownish-black, but anterior and posterior surfaces of fore, mid, and hind tibiae light brown. Pulvilli yellow; claws light brown with darker tip. Upper and lower calypters dark brown. Abdomen translucent light yellow, syntergite 1+2 to tergite 4 with an interrupted median brownish black vitta, tergite 4 brownish-black-tinged laterally on posterior region; tergite 5 brownish-black, but anterior 1/6 light yellow.

Head ( Fig. 1A, C–D ). Ocellar setae long, divergent and proclinate. Inner vertical seta decussate and long, outer vertical seta absent. Width of parafacial, measured at distance between inner margin of eye and antennal insertion, 2x height of gena. Arista long plumose. Fronto-orbital plate with lowermost frontal seta not reaching antennal insertion. Postpedicel about 1.5x the combined lengths of scape and pedicel. Fronto-orbital plate with setulae throughout its length, parafacial bare. Frontal vitta narrowed dorsally. Lower facial margin protruding, visible in profile. Vibrissa arising above lower facial margin. Gena about 2.5x eye height. Prementum about 0.5x head height. Labellum developed, about 0.1x as long as prementum.

Thorax ( Fig. 1A, C ). Acrostichal setae 3+2. Dorsocentral setae 3+4. Intra-alar setae 1+3. Intra-postalar seta absent. Supra-alar setae 2+4. Postpronotal lobe with 5 setae. Notopleuron with 2 equal-sized setae. Postalar callus with 3 setae, the outer one weak. Propleuron and prosternum bare. Anepimerum with numerous long setae. Katepisternal setae 2+1. Scutellum with one pair of basal, one pair of long and divergent subapical, and one pair of strong, straight apical setae; numerous erect discal setae. Postmetacoxal area membranous. Anatergite bare. Posterior spiracle with posterior lappet larger than anterior. Katepimeron setulose. Wing. Costal spine undeveloped. Vein R 4+5 with setulae ventrally and dorsally at base; with numerous erect setae. Legs. Fore femur with posterodorsal and posteroventral rows of setae; fore tibia with 7 median anterodorsal, 2 posteroventral in apical third, 3 preapical, 2 anterodorsal and 1 posteroventral setae. Mid femur with 8 anteroventral, 5 anteromedian, 2 preapical, and 2 posteroventral setae; mid tibia with 2 median anteroventral and 1 posteroventral setae. Hind femur with posterodorsal and posteroventral rows of setae. Hind tibia with rows of anterodorsal (6) and posterodrosal setae (6), 3 submedian posteroventral, 4 preapical, 2 anterodorsal, and 2 posteorventral setae. Claws straight, with curved tip.

Abdomen ( Fig. 1A, C ). Syntergite 1+2 with mid-dorsal longitudinal depression extending to posterior margin. Syntergite 1+2 with at least 3 pairs of lateral marginal setae; tergite 3 with discal setae covering all of tergite 3 except for small anterolateral region overlapped by wing, tergite 4 with discal setae arranged in at least three transverse rows and tergite 5 entirely covered with spine-like setae.

Terminalia. Not dissected, only the lectotype and paralectotypes were available.

Female. Unknown.

Biology. Unknown.

Distribution. Mexico (Veracruz); Costa Rica (San José); Nicaragua (Chontales); Venezuela.

Figures

FIGURE 1. Eudexia formidabilis (Bigot, 1889), lectotype male (NHMUK). A. Dorsal habitus. B. Labels. C. Lateral habitus. D. Head, frontal view.