Schildia gracillima ( Walker, 1855 )

Dikow, Torsten & Bayless, Keith M., 2009, Taxonomic revision of the genus Schildia Aldrich, 1923 (Diptera: Asilidae: Leptogastrinae) with the description of new extant and extinct species, Insect Systematics & Evolution 40, pp. 253-289 : 271-273

Schildia gracillima ( Walker, 1855) ( Figs 16–18 , 38 ) Leptogaster gracillimus ( Walker 1855: 770 , 722)

Schildia gracillima ( Martin 1965: 110, 114; Martin 1968b: 5; Martin 1975: 190).

Schildia ocellata ( Martin 1975: 189, 192). syn.n.

Diagnosis. This species is distinguished from its congeners by its long body length, the narrow vertex that is as narrow as the face, the laterally apruinose occiput, and the very short and dense trichoid spicules.

Redescription. Head: Face silver pruinose, wide, wider than adjacent ommatidium; mystax light yellow, 2 setae; vertex narrow, narrower than face at clypeal–facial margin, silver pruinose; occipital triangle apruinose, distance between triangle and median eye margin less than adjacent ommatidium; occiput thinly silver pruinose along eye margin, medially silver pruinose, laterally apruinose; postocular setae short, brown; proboscis brown; Antennae: scape and pedicel light brown, light brown setae dorsally and ventrally; postpedicel proximally light yellow, brown distally, silver pruinose, about 1.5 times as long as combined length of scape and pedicel; stylus brown, about 2/3 as long as postpedicel, composed of 1 element.

Th orax: Predominantly light brown, parts silver and brown pruinose; antepronotum, postpronotum, and median postpronotal lobes silver pruinose; lateral postpronotal lobes apruinose, light yellow; scutum brown, predominantly apruinose, only posterior margin silver pruinose, 2 yellow lateral longitudinal stripes originating at anterior margin but not reaching posterior margin, broader anteriorly and pointed posteriorly, 2 yellow lateral spots positioned predominantly presutural; presutural dc setae: 2 short, 1 intermediate, 2 long, postsutural dc setae: 2 anteriorly oriented as long as intermediate presutural dc setae, acr setae absent, 1 npl and 1 spa seta; anepisternum predominantly silver pruinose sometimes apruinose dorsally, few yellow anepisternal setae on anterior and dorsal margins; anepimeron anteriorly silver and posteriorly brown pruinose, proepimeron silver pruinose, katepisternum anteriorly silver and posteriorly brown pruinose, meron+metanepisternum anteriorly apruinose and posteriorly silver pruinose, metkatepisternum yellow, silver pruinose; scutellum yellow posteriorly and brown medially, silver pruinose, 4–6 very short apical scutellar setae; Legs: yellow to brown; coxae and trochanters light yellow, trochanters sometimes brown ventrally; pro and mes femora light yellow with 1 transverse light brown band medially, met femur mostly light brown to brown, clubbed in distal 2/5, club brown, yellow transverse band at proximal margin of club, scattered brown setae on pro and mes femora, met femur with distinct rows of brown macrosetae; pro and mes tibiae light yellow with 1 light brown transverse band which is sometimes diffi cult to discern, met tibia brown with yellow transverse band in distal half, 2 times wider than width of tibia, all tibiae with brown erect macrosetae in rows, pro and mes tibiae with 2 long apical macrosetae, met tibia with 2 apical, 2 medial in distal quarter, 4 lateral macrosetae spaced along tibia; tarsus light yellow to light brown, proximal tarsomere always longer than 2 following tarsomeres combined, short and long macrosetae on all tarsomeres; all empodia 1/3 as long as median claw; median claw about 3/4 as long as lateral claw; Wings: length = 5.3–7.8 mm; few microtrichia scattered on wing, trichoid spicules very short, densely arranged, symmetrical dorsally and ventrally, 40–50 on M1 between r-m and diversion of M1 and M2; cell d large, terminating in M1 and M2, r-m situated at separation of M 3 and CuA 1; R 1 reaching C at the point where R 5 joins C but distal to M 1 joining C, R2+3 straight proximally and smoothly arching posteriad distally; halter light yellow, knob dark brown, length = 0.9–1.3 mm.

Abdomen: Brown, T1 yellow, T2 yellow anteriorly, sometimes T3-6 also yellow anteriorly; T2 length = 4.9–5.1 mm, T2 with yellow transverse band medially, T2–3 with short, erect, evenly spaced macrosetae, remaining T with irregularly spaced and longer macrosetae, T7–8 with large lateral sensory areas; Male terminalia ( Figs. 16–18 ): epandrial halves fused medially, distal tip arching dorsad, pointed; epandrium and hypandrium entirely fused proximally, gonocoxite easily distinguishable but fused to hypandrium, distinct ventral suture discernible; gonostyli bifid with two apices; Aedeagus: not protruding from hypopygium; dorsal aedeagal sheath with curved ventral protuberances; lateral ejaculatory process cylindrical; Female genitalia: spermathecae occupying only segment 8, individual spermathecal ducts long and coiled; spermathecal reservoirs not sclerotized, as wide as individual ducts, forming a coil.

Type material. The ♂ holotype of Leptogaster gracillimus is labeled “ Type (circular label, green submarginal margin) Leptogaster gracillimus Wlk. (handwritten) / Brazil Parà H.W. Bates 51-55 (handwritten) / Holotype (circular label, red border) / Holotype Leptogaster gracillimus Walker det. J.E. Chainey 1982 (handwritten) / Bangil (circular label, handwritten) / gracillimus (handwritten)” ( BMNH). The specimen is directly mounted and is in good condition (missing some legs) .

The ♂ holotype of Schildia ocellata is labeled “Ter. AMAPA Rio Amapari J. Lane col. (handwritten, black submarginal border) / 2.VII.59 (handwritten) / ♂ / HOLOTYPE Schildia ocellata Chas. H. Martin (species name handwritten, red label) / Schildia ocellata Martin Det. C.H. Martin 19 (species name handwritten, black submarginal border) / Schildia gracillima ( Walker, 1855) det. T. Dikow & K. Bayless 2007” ( MZSP). The specimen is mounted on label paper and is in good condition (antennae broken) .

Specimens. 1♀ Utinga, Belem , 01°27’S 048°30’W, 18.vi.1963, M. Amaral ( MZSP), 1? Mocambo do Espirito Santo , 00°42’N 055°55’W, 26.v.1977, M. Torres ( MZSP); Peru: 1♀ no locality and date ( ZSMC) .

Distribution. Brazil, Peru ( Fig. 38 ). Biodiversity hotspot/high-biodiversity wilderness area: –/Amazonia ( Fig. 38 ).

Remarks. Schildia ocellata , described from north-eastern Brazil by Martin in 1975, is here synonymized with S. gracillima as the holotypes are morphologically indistinguishable.

Figures

Figs 13–24. Male terminalia of Schildia species with gonostyli (dark grey) and lateral processes of gonostyli (light grey) shaded in lateral views. (13–15) S. adina sp.n.: 13, lateral; 14, dorsal; 15, ventral. (16–18) S. gracillima: 16, lateral; 17, dorsal; 18, ventral. (19–21) S. guatemalae: 19, lateral; 20, dorsal; 21, ventral. (22–24) S. jamaicensis: 22, lateral; 23, dorsal; 24, ventral. Scale bar = 1 mm.

Fig. 38. Map of the Neotropical region with biodiversity hotspots and wilderness areas, shaded in grey, showing distribution of Schildia alphus (square), S. caliginosa sp.n. (star), S. fragilis (circle) and S. gracillima (triangle). Open symbols, type localities.