Leptogaster flavipes Loew, 1862

Dennis, D. Steve, Barnes, Jeffrey K. & Knutson, Lloyd, 2008, Pupal cases of Nearctic robber flies (Diptera: Asilidae), Zootaxa 1868 (1), pp. 1-98 : 19-20

Leptogaster flavipes Loew

The following redescription is reworked from Malloch’s (1917) and Bromley’s (1946) descriptions to conform to our format. It is based mainly on a male specimen studied by Malloch (1917). The larva was found in soil under a rotten log at Cottonwood Grove, Urbana, Illinois on April 23, 1916. It pupated on May 5, and the adult emerged on May 19, indicating an approximate two­week pupal stage for this species. Melin (1923) observed that L. cylindrica and L. guttiventris Zetterstedt have pupal periods of about 14– 45 and 24 days, respectively.

It should be noted that we have not been able to locate the specimens upon which Malloch (1917) and Bromley (1946) based their descriptions. Thus, we have not been able to determine if their reference to “bristle” is our “spine” or “spur,” in particular on the abdominal segments.

Redescription: Length 7 mm. Integument subshining light yellowish; spines and other processes dark brown. Head with poorly developed, tuberculate, ventrally ridged anterior antennal processes, each with a lateral or dorsal bristle; distinct posterior antennal processes absent, but ridged callosity present. Facial area with 3 small, median callosities in vertical row between posterior antennal callosities; center of facial area with small callosity slightly higher than posterior antennal callosities; median bristles present on each side of midline. Prothoracic spiracle small, round, distinctly elevated. Posterior mesothoracic callosity absent, but 2 bristles present. Dorsal surface of thorax with anterior and posterior bristles on each side of midline forming the corners of a square or rectangle. Apex of hind leg sheath reaching slightly beyond posterior margin of abdominal segment 3. Abdominal spiracles minute.

Abdominal segment 1 with dorsal transverse row of 6 median slender spines, with bristles between first and second spine and second and third spine counting from each side and 4–5 bristles on each side lateral to outermost spine.

Segment 2 with 5 long, posteriorly curved, hook­like spines; bristles present between each pair of spines. Segments 3–7 similar to 2, but with 6 spines, which become smaller posteriorly. Abdominal bristles longer than each segment.

Segment 9 with small processes. All abdominal segments with 4 bristles laterally behind each spiracle and 3 long bristles ventrally on each side of midline.