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Siricidae (Hymenoptera: Symphyta: Siricoidea) of the Western Hemisphere
CJAI 21, July, 2012
doi: 10.3752/cjai.2012.21
Nathan M. Schiff, Henri Goulet, David R. Smith, Caroline Boudreault, A. Dan Wilson, and Brian E. Scheffler

Genus Sirotremex Smith

Fig. C18.1 (male lateral habitus)

Sirotremex Smith, 1988: 244. Type species: Sirotremex flammeus Smith; monotypic.

Diagnostic Combination

Both sexes of Sirotremex probably (female unknown) are recognized by the fore wing with a broadly rounded apex and a short 3R1 cell (2.2 times as wide as long), and the flagellum with 10 or 11 short flagellomeres (middle flagellomeres 1.5 times as long as wide).


Color. Surfaces dark brown and without metallic reflections.

Head. Antennal sockets with distance between their inner edges 2.5 times distance between inner edge of eye and outer socket edge (Fig. C18.2, in black). Distance between inner edges of lateral ocelli 1.1 times as long as distance between outer edge of lateral ocellus and nearest edge of eye (Fig. C18.2, in white). Maximum distance between outer edges of eye longer than maximum width of head (thus, in frontal view, genal edge intersected by outer edges of eyes) or slightly shorter (Figs. C1.18, C18.2). Minimum distance between inner edges of eyes 1.6 times maximum eye height (Fig. C18.2, in red). Gena without ridge behind eye and without white spot, with large pits, each pit not elevated along posterior edge as low tooth. Head with setae sharp at apex. Antenna with 10 or 11 flagellomeres, and middle flagellomeres in dorsal view 1.5 times as long as high; middle flagellomeres with sensory pits on ventral surface, and apical 5 or 6 flagellomeres each with sensory pits on inner surface only, but without oval impression on inner dorsal and inner ventral surfaces.

Thorax. Pronotum smooth or pitted over less than 0.5 of anterior vertical surface. Mesoscutum densely pitted over median 0.5–0.7 only. Mesotarsomere 1 in lateral view enlarged, its dorsal and ventral edges quite divergent in basal half and base of tarsomere about 0.5 times its maximum width. Metatibia with two apical spurs, in male in lateral view metatibia 3.7–4.1 times as long as maximum width. Metatarsomere 2 length and height not described as female unknown. Metatarsomere 5 shorter than metatarsomeres 2 + 3. Fore wing with apex broadly rounded (Fig. B1.49), with vein 2r–m joined to cell 2M (as in Fig. B1.71), with vein 2r–m present, with cell 1Rs2 about as wide as long (Fig. B1.51), with cell 3R1 2.2 times as long as wide (Fig. B1.53), with vein 2r-rs joining stigma near middle, with stigma gradually attenuated even distal to junction with vein 2r-rs (as in Fig. B1.25), with vein Cu1 usually present, with vein 1cu–a joining vein Cu about mid way between veins 1m–cu and M, with vein 2A extending along wing posterior edge for 0.4 times length of cell 1A length (as in Fig. A3.30), and with vein 3A absent. Hind wing with anal cell.

Abdomen. Cornus, median basin, sheath, and ovipositor not described as female unknown.

Diversity and distribution

One species known only from two males is recorded from northwestern Mexico (Smith 1978; Taeger and Blank 2011, Taeger et al. 2010).

Species List

One species treated: