Efferia triton (Osten Sacken)

Dennis, D. Steve, Barnes, Jeffrey K. & Knutson, Lloyd, 2008, Pupal cases of Nearctic robber flies (Diptera: Asilidae), Zootaxa 1868 (1), pp. 1-98 : 74-75

Efferia triton (Osten Sacken)

( Fig. 45 )

In the United States National Museum there is one male Efferia triton pupal case with associated pinned adult labeled " S. Rita Mts. , Ar.; 30­5; Coll. Hubbard & Schwarz."

Description: Greatest length, including anterior antennal processes, 19.5 mm; greatest width of thorax 4.5 mm; greatest width of abdomen 4.0 mm, tapering to 2.0 mm at greatest width of abdominal segment 8. Integument subshining light golden brown; spines and other processes glistening reddish brown, spines on dorsum of abdomen more glistening reddish; bristle­like spines light reddish brown.

Head with pair of dorsally flattened, ventrally wedge­shaped anterior antennal processes not joined at base and group of 3 basally fused posterior antennal processes located ventrolaterally on each side; middle and outer processes closer together and fused for greater distance, appearing shorter than inner process; outer posterior process wide, apically blunt, slightly curved medially, with flattened underside basally toward dorsum; inner and middle posterior processes narrow, apically rounded and straight; with small space underneath outer posterior process. Labral sheath slightly rugose, with apical keel. Proboscial sheath rugose on each side of midline and around elongate tubercle on each side of midline posteriorly; with median, basally concave tubercle slightly posterior to lateral tubercles. Maxillary sheath rugose, with apically rounded process.

Anterior coxal sheath irregularly rugulose and rugose on each side of midline, with anterior, median, longitudinal split. Prothoracic spiracle elongate­oval, slightly elevated, not on callosity, situated midlaterally at anterior margin of thorax. Anterior mesothoracic spines consisting of pair of short, apically acute, subequal spines at base of sheath of mid legs; posterior spine broad basally, straight; anterior spine narrower, curved posteriorly. Posterior mesothoracic callosity large, mostly smooth, except for rugose anterior margin, with small, apically rounded posterior mesothoracic spine; posterior and dorsal margins sclerotized. Wing sheath mostly rugulose with small basal and median tubercles. Thoracic area above wing sheath smooth to slightly rugulose. Apex of hind leg sheath reaching to middle of abdominal segment 3.

Abdominal spiracles semi­oval, light reddish brown, slightly elevated, situated along midline laterally.

Abdominal segment 1 with dorsal transverse row of 18 mostly long, straight to apically recurved spurs; dorsolateral bristle­like spines absent; with 6 alternately long and short lateral bristle­like spines behind spiracle on each side; venter obscured by wing and leg sheaths.

Segment 2 with dorsomedian transverse row of 12 alternating long, straight spurs and short spines; pair of short dorsomedian spines; 5 short dorsolateral spines; 4 dorsolateral bristle­like spines; and 6–8 bristle­like spines behind each spiracle.

Segments 3–6 similar to segment 2, but with 1–4 short dorsolateral spines, single short median spine, 3–5 dorsolateral bristle­like spines, and 6 bristle­like spines behind each spiracle.

Segment 7 with dorsal, transverse row of 13 alternating long spurs and short spines, 3 dorsolateral bristlelike spines, and 5 lateral bristle­like spines behind each spiracle.

Segment 2 with 5 ventral bristle­like spines on each side of and slightly extending under sheaths of mid legs; segments 3–7 with 13–22 ventral bristle­like spines of irregular length.

Segment 8 with 3 long dorsal spurs on each side of midline; spiracle not visible; with 6–8 lateral bristlelike spines of irregular length; and ventral transverse row of 16 bristle­like spines on posterior margin.

Segment 9 with pair of short dorsal posterolateral processes; pair of still shorter ventral posterolateral processes; pair of very small posteroventral tubercles; and pair of small ventromedial tubercles; male with pair of larger, widely separated anteroventral tubercles.

Figures

FIGURE 45. Efferia triton (Osten Sacken), thorax, ventrolateral view. Abbreviations: amsp = anterior mesothoracic spine, pmc = posterior mesothoracic callosity, wsh = wing sheath.