Laphria canis Williston

Dennis, D. Steve & Barnes, Jeffrey K., 2013, Pupal cases of four Nearctic species of Laphria (Diptera: Asilidae), Zootaxa 3681 (4), pp. 478-492 : 479-481

Laphria canis Williston

( Fig. 1 )

Laphria canis Williston, 1883: 31 .

The following description is based on two pupal cases. One case with a pinned female is labeled, “Harrisburg PA June -30-13, H.B. Collector, USNMENT00876523”; a separately pinned case on a point is labeled, “”1550e Hopk. U.S., Tryon NC, W.F. Fiske Collector, USNMENT00876741”. The latter is believed to be the pupal case of a female that has crusted material on abdominal segments 8 and 9.

In the USNM there is one Hopkins record card that indicates the following collection and identification information for specimen (i.e., pupal case) 1550e, “ Laphria canis Will. Det. C.T.G. ; Chestnut, Saluda, N.C., May 20, 1903 ”. We believe that the reference to “Chestnut” indicates that the pupal case was recovered from a chestnut tree. The town of Saluda in North Carolina is approximately 6 miles from Tryon and both towns are often referred to as the Saluda/Tryon area.

Description. Pupal cases mostly straight. Greatest length, including anterior antennal processes 10.0–11.0 mm; greatest width of thorax 2.0– 2.1 mm; greatest width of abdomen 1.5–2.0 mm, tapering to 1.0– 1.1 mm at greatest width of abdominal segment 8. Integument subshining light golden brown, becoming darker apically on wing sheaths and to a lesser extent on leg sheaths. Spines and other processes glistening reddish brown; spines uniformly colored or either darker basally or on apical half; processes of head and abdominal segment 9 darker apically ( Fig. 1 ).

Head with pair of basally rugose, recurved, dorsally rounded, ventrally wedge-shaped anterior antennal processes, these processes not joined at base; with group of 4 basally rugose, dorsally rounded, ventrally wedgeshaped posterior antennal processes curving and becoming shorter posteriorly; inner or first posterior process longer than and separated from outer processes by flattened area of cuticle; outer 3 posterior processes basally fused and very close together, becoming shorter posteriorly; sensory pore on outermost process not visible. Facial area with 3 small, basally fused median spines on each side of midline; middle spine shortest, with basal, small posterior bristlelike spine; with single, larger, lateral spine. Labral sheath narrow, elongate, smooth with median furrow. Palpal sheaths not visible on each side of labral sheath. Proboscidal (=proboscial, olim, incorrect spelling) sheath smooth, with median furrow, posteriorly elongate and extending over posterior coxal sheath. Maxillary sheath smooth, extending 1/2 –2/3 length of proboscidal sheath, with posterior, inner, darker sclerotized area.

Anterior coxal sheath smooth, with anteromedian longitudinal split. Posterior coxal sheath smooth, folded inward. Prothoracic spiracle light reddish brown, spherical, on slight callosity, situated midlaterally at anterior margin of thorax. Anterior mesothoracic spines present on each side of thorax above bases of and extending over mid leg sheaths, consisting of anterior pair of basally broad and fused, dorsoventrally flattened to rounded, ventrally wedge-shaped, straight to posteriorly curved spines with sclerotized edges, and single, short basally broad, dorsally flattened, ventrally wedge-shaped, straight, posterior spine widely separated from anterior pair. Posterior mesothoracic callosity at base of wing sheath bulbous, with short, broadly rounded posterior mesothoracic spine consisting of sclerotized posterior ridge. Wing sheath smooth, with elongate grooves. Thoracic area above wing sheath smooth. Apex of hind leg sheath (leg sheath 3) reaching to between middle and posterior margin of abdominal segment 3. Leg sheaths apically bilobed with median projection.

Abdominal segments 1–6 each with dorsomedian transverse row of long spines alternating with 1–3 short spines, becoming larger and longer posteriorly; segments 4–5 with 2 long spines on either side of midline curving anteriorly; segment 7 with more subequal, longer spines. Dorsolateral and ventral subequal bristlelike spines becoming longer posteriorly; long, lateral bristlelike spines becoming longer towards venter.

Spiracles of abdominal segments 1–7 situated along midline laterally, light reddish brown, very small, spherical, flush or almost flush with cuticle.

Abdominal segment 1 with dorsal transverse row of 23–26 spines; median 2–4 spines short; lateral 3–8 spines long, with 1–3 short spines between long spines; 4–6 short dorsolateral spines present; dorsolateral bristlelike spines absent; 3 long postspiracular bristlelike spines present; venter obscured by wing and leg sheaths.

Abdominal segment 2 with dorsal transverse row of 21–24 spines consisting of 2–3 short median spines, flanked on each side by 5–6 long lateral spines with 1–2 short spines between each pair of long spines, then 3–8 dorsolateral short spines (some vestigial); with 3–4 dorsolateral bristlelike short spines; with 3 long bristlelike postspiracular spines; and with 1–3 ventral bristlelike spines on each side of wing and leg sheaths.

Abdominal segment 3 with dorsal transverse row of 21–24 spines consisting of 2–3 short median spines (one bifurcate, the other vestigial) and 5–7 spines on each side, some alternating long and short, then 5 short dorsolateral spines; with 3–4 short dorsolateral bristlelike spines; with 3–4 long bristlelike postspiracular spines; with 13–14 long and short ventral bristlelike spines, some median spines very short or rubbed-off by wing and leg sheaths.

Abdominal segment 4 with dorsal transverse row of 19–21 spines consisting of 2–3 short median spines, flanked by 3–5 spines on each side, some alternating long and short, then 4–5 dorsolateral short spines; with 3–4 short dorsolateral bristlelike spines; with 3 long postspiracular bristlelike spines; with ventral transverse row of 13– 15 long and short bristlelike spines with a median space

Abdominal segment 5 with dorsal transverse row of 20 spines consisting of 2–3 short median spines, flanked by 2–5 spines on each side, some alternating long and short, then 3–7 dorsolateral short spines; with 4 dorsolateral bristlelike spines; with 2–4 long postspiracular bristlelike spines; with ventral transverse row of 15–18 long and short bristlelike spines with a median space.

Abdominal segment 6 with dorsal transverse row of 11–14 spines consisting of 2 short spines, 3–6 long and short spines, and 1–4 short outer spines on each side of median space; with 4–5 short dorsolateral bristlelike spines; with 3–4 long postspiracular bristlelike spines; with ventral transverse row of 13–15 long and short bristlelike spines divided by a slight to obvious median space.

Abdominal segment 7 with dorsal transverse row of 6–10 spines consisting l short spine and 2–5 long and short spines on each side of a median space; with 3–5 dorsolateral bristlelike short spines; with 3–4 long postspiracular bristlelike spines; with ventral transverse row of 15–16 long and short bristlelike spines, including 2–3 median short spines.

Segments 8 and 9 slightly curved ventrally. Segment 8 with 1 dorsal spine on each side of midline; dorsolateral, lateral and ventral bristlelike spines absent; with midventral callosities forming a “V” on centerline; spiracle small, spherical to oval, light reddish brown, flush with cuticle.

Segment 9 with small, short, basally rugulose dorsolateral processes curved towards each other, each with outer surface flat to rounded, inner surface slightly flattened to wedge-shaped; with larger, longer, straight, basally rugulose ventrolateral processes, each with outer surface flat, inner surface wedge-shaped.

Figures

FIGURE 1. Laphria canis Williston female pupal case, lateral view with abdominal segments numbered, Dauphin County, Pennsylvania. Abbreviations: aap = anterior antennal process, amsp = anterior mesothoracic spine, dpp = dorsal posterolateral process, pap = posterior antennal process, pmc = posterior mesothoracic callosity, pthsr = prothoracic spiracle, vpp = ventral posterolateral process, wsh = wing sheath.