Syringogaster tenuipes Marshall & Buck, 2009

Marshall, S. A., Buck, M., Skevington, J. H. & Grimaldi, D., 2009, A revision of the family Syringogastridae (Diptera: Diopsoidea), Zootaxa 1996 (1), pp. 1-80 : 69-71

Syringogaster tenuipes Marshall & Buck , new species

Figs. 59–62; Plate 1D; Map 9

DESCRIPTION: Head orange-brown except darker ocellar tubercle. Vertex strongly convex at middle. Ocellar triangle shining, bordered on each side by a row of minute inclinate bristles, anterior apex separated from frontal margin by width of first flagellomere; remainder of frons tomentose and dull. Ocellar bristles strong. Anteromedial surface of pedicel shining. Parafacial with scattered dark setulae around vibrissal angle. Gena and subgena subequal in height, gena with a row of fine black bristles.

Thorax orange, variably marked with medium brown as follows: mesoscutum behind transverse suture, scutellum, mediotergite, spot on katepisternum behind fore coxae, hypopleuron (especially dark band from mid coxa to prespiracular process), and postmetacoxal bridge. Pronotal collar with a strong transverse carina on each side; antepronotum and propleuron shining, notum otherwise dull, tomentose and mostly sparsely setulose. Notopleural carina and humeral carina small but distinct, postpronotum slightly raised, dull, tomentose posteriorly; black humeral carina short, restricted to anterior face of humeral pit. Mesopleuron shining except for tomentose posterodorsal area of anepisternum; lower anepisternum, katepisternum and anepimeron with scattered fine pale bristles. Laterotergite with carinate anterior margin raised well above anepimeron. First prespiracular process small and knob-like, at the end of an elevated ridge; second prespiracular process shining and triangular. Subspiracular carina low, anterior part bare, posterior part tomentose dorsally. Supra-alar carina distinct but low. Fore coxa and trochanter white in males (yellowish in females), otherwise fore leg yellow to orange-brown; all fore leg bristles pale. Fore femur without black spinules ventrally. Mid femur white basally, rest of leg orange-brown. Mid tarsomeres 1–3 and basal half of tarsomere 4 with antero- and posteroventral sawlines. Hind femur relatively slender, 4.1–4.7X as long as wide in lateral view, with a white basal ring followed by a brown ring of similar length; remainder of leg orangebrown. Hind femur with anteroventral row of 5–7 spines extending over distal 1/2–3/5 of femur, posteroventral row shorter. Hind tibia with apex trilobate, lobes unequal, apicoventral lobe more prominent than other lobes. Hind tarsus with anteroventral sawlines on tarsomeres 1–4, posteroventral sawlines of tarsomeres 2–3 just over half as long as tarsomeres; both sawlines of tarsomere 4 extremely shortened, consisting of 1–2 spinules only.

Wing clear with large and dark patches over all crossveins, patches over basal crossveins forming complete band from front to hind margin of wing; a large, dark oval discal band from apex of R 2+3 to dm-cu, very faintly reaching hind margin of wing, broadly connected at level of M with brown spot around r-m and adjacent section of cell r 2+3. R 2+3 running to costa at an acute angle, not distinctly turned up near apex. Cell r 4+5 gradually widening beyond r-m, not abruptly tapered to r-m; r-m about half as long as dm-cu. Fork of CuA distal of bm-cu by about 0.7–1.0X length of bm-cu; CuA 1 and A 1 +CuA 2 extending almost to wing margin.

Abdomen: Syntergite 1–3 elongate, tergites 1 and 2 parallel-sided; tergite 1 granulose and wrinkled, sparsely tomentose, tergites 2–3 subshining with sparse setulae and a few easily overlooked microtrichia. Background color reddish, syntergite often with a dark basal ring or dorsobasal spot and median ring or dorsomedial spot (dorsally often elongate); tergites 4–6 (and usually part of 3) dark brown (becoming paler posteriorly). Surface almost smooth; minute pitting visible only under very high magnification. Tergites 2 and 3 fused but delineated by a distinct suture; tergite 4 not fused with tergite 3.

Female terminalia: Four spermathecae in two pairs, each pair made up of close but distinctly separated, dark, acorn-shaped spermatheca; each spermatheca ringed by grooves, cylindrical cap about a third as long and wide as theca.

Male terminalia: Tergites 5 and 6 unmodified, ventrolateral margins straight. Spiracles 5 in membrane, spiracles 6 in tergite close to margin. Sternites 5 and 6 each reduced to a pair of small, pale sclerites each with several long bristles; synsternite 7+8 weak ventrally. Epandrium about twice as wide as long. Cercus almost sessile, long-setose, much smaller than surstylus. Surstylus nearly circular, slightly longer than wide, outer surface with bristles that are mostly longer than surstylus. Hypandrium without internal interruptions or articulations; anterior U-shaped portion forming simple ventral band without anterior apodemes; hypandrial bridge narrow. Ventral hypandrial lobe slightly shorter than in S. apiculata , round and long-setose at apex; posterior part of hypandrial arm short and broad, articulating with pregonite with three lobes of characteristic shape; heavily sclerotized, black medial lobe relatively narrow and parallel sided (much narrower than in S. apiculata ), pale ventral lobe triangular and not very long, posterior lobe pale and broadly rounded. Subepandrial sclerite reduced and inconspicuous. Basiphallus narrowly cylindrical at base, expanded distally;

dorsoapical lobes asymmetrical, left lobe rounded in ventral (axial) view; right lobe with carina on inner margin and shallow depression on right side of carina. Distiphallus moderately complex, directed sinistrally, distally with one large, sickle-shaped lobe and one short and thin finger-like lobe; at base of large lobe with conspicuous lamellate, apically notched projection.

TYPE MATERIAL: Holotype ♂ ( UASC; see also photograph of live specimen, Plate 1D) and paratype ♀ ( DEBU): BOLIVIA. La Paz, Heath River Wildlife Centre, 12°40’S, 68°42’W, 28.iv–12.v.2007, S.A. Marshall. Other paratypes: same as holotype but collected by J. Kits (1♂, DEBU). ECUADOR: Napo, Puerto Misahuallí, 350 m, ii.1983, M.J. Sharkey (1♀, CNCI). PERU. Madre de Dios, Los Amigos Biological Station , 2–14.vi.2006, S.M. Paiero & J. Klymko (1♂, 2♀; 1♀ with all but legs removed for sequencing; DEBU, CNCI).

OTHER MATERIAL EXAMINED (unassociated female tentatively identified as S. tenuipes ): PERU. Madre de Dios, Manú, Río Manú, Pakitza , 250 m, 12°7’S, 70°58’W, 9–23.ix.1988. A. Freidberg (1♀, USNM).

ETYMOLOGY: The name tenuipes refers to the relatively slender hind femur.

COMMENTS: This species is extremely similar to the sympatric S. apiculata (see comments under that species).

Fossil species: