Stenopogon rufibarbis Bromley, 1931

Dennis, D. Steve, Barnes, Jeffrey K. & Knutson, Lloyd, 2008, Pupal cases of Nearctic robber flies (Diptera: Asilidae), Zootaxa 1868 (1), pp. 1-98 : 38-39

Stenopogon rufibarbis Bromley

The following description is based on two pupal cases with pinned females from the United States National Museum labeled "Crater Lake, Or.; July 28, 1920; H.G. Dyar coll." and "Azusa, Cal.; May 17, '25; S.W. Bromley Collection 1955."

Description: Greatest length, including anterior antennal processes, 14.6 mm; greatest width of thorax 4.4 mm; greatest width of abdomen 3.1 mm, tapering to 2.7 mm at greatest width of abdominal segment 8. Integument subshining pale whitish to golden brown on wing sheath; spines and other processes glistening reddish brown, darker apically, except for uniformly colored dorsal abdominal spurs and spines.

Head with pair of dorsally flattened, ventrally wedge­shaped anterior antennal processes not joined at base and group of 3 apically rounded to acute, basally fused posterior antennal processes about as long as anterior antennal processes, located ventrolaterally on each side; middle and outer posterior processes fused for greater distance, slightly closer together, thus appearing shorter than inner or first posterior process; outer or third posterior process elbowed, sometimes with outer, flattened area with posterior lip. Labral sheath swollen, smooth except for median grooves along entire length of sheath, lacking distinct keel. Proboscial sheath smooth to slightly rugulose, with median furrow running entire length and small posterior tubercle at end of furrow. Maxillary sheath smooth to slightly rugulose, extending down half length of proboscial sheath.

Anterior coxal sheath smooth to irregularly rugulose, with anterior, median, longitudinal split. Prothoracic spiracle oval, on slight callosity with small anterior tubercle, situated midlaterally at anterior margin of thorax. Side of thorax, above base of mid leg sheath, with pair of very short, usually subequal, rugose, apically rounded to blunt and furcate, straight anterior mesothoracic spines on small rugose callosity. Posterior mesothoracic callosity small, smooth, lacking posterior mesothoracic spine. Wing sheath smooth to rugulose, lacking median or basal tubercle. Thoracic area above wing sheath smooth to irregularly rugulose. Apex of hind leg sheath reaching between posterior margin of abdominal segment 2 and middle of abdominal segment 3.

Abdominal spiracles oval, almost flush with surface, light yellowish brown, often difficult to see.

Abdominal segment 1 with 2–3 straight to apically recurved, acuminate dorsal spurs on each side of midline; dorsolateral bristle­like spines absent; 3 yellowish lateral bristle­like spines behind each spiracle; venter obscured by wing and leg sheaths.

Segments 2–6 with dorsal transverse row of 13–16 alternating long, acuminate spurs and short, acuminate spines continued dorsolaterally with 3–7 short bristle­like spines; transverse row often with 2–3 median spines bifurcate or with other short spines sometimes in pairs.

Segment 7 similar to segments 2–6, but with dorsal transverse row of 12 alternating long spurs and short spines continued dorsolaterally by 0–2 short bristle­like spines.

Segments 2–7 lacking ventral bristle­like spines; 3 lateral bristle­like spines behind each spiracle.

Segments 8–9 somewhat bulbous. Segment 8 with 2–4 (usually 4) dorsal spurs of unequal length on each side of midline; lacking dorsolateral, lateral, or ventral spines or bristle­like spines; spiracle not visible. Segment 9 with pair of long spine­like dorsal posterolateral and shorter spine­like ventral posterolateral processes; processes straight or slightly curved dorsally; female lacking ventromedian tubercles.