Mimesa infossa Ma, Li and Chen

Ma, Li, Li, Qiang & Chen, Xue-Xin, 2008, The genus Mimesa in China with descriptions of two new species (Hymenoptera: Apoidea: Crabronidae), Zootaxa 1745, pp. 19-29 : 22-24

1. Mimesa infossa Ma, Li and Chen , sp. nov.

( Figs. 1–5 )

Diagnosis: The male of this species can be distinguished from the similar M. equestris (Fabricius, 1804) and other species of the genus by the following combination of characters: lower frons with deep depression; antennal segments IV–XI beneath with linear carinae; mesopleuron alutaceous, with contiguous, slender, longitudinal rugae; dorsum and posterior surface of propodeum with dense, slender, longitudinal rugae; free margin of clypeus with two semicircular prominences medially; and interantennal tooth conspicuous.

Description: Male. Body length 5.0–7.0 mm. Black, weakly shiny; mandible apically bright reddish brown; tibial spurs fulvous; gastral tergum I posteriorly, tergum II wholly, terga III and IV posteriorly, and sternum II reddish brown. Setae on clypeus silvery, dense, on frons, vertex, thorax, propodeum, leg and petiole silvery, long, somewhat sparse.

Clypeus with dense, fine punctures; free margin with two semicircular prominences medially; area near apex without tubercle ( Fig. 1 ); basal half of clypeal disk moderately elevated. Mandible bidentate apically. Interantennal tooth conspicuous ( Fig. 1 ). Antenna slender, segments IV–XI beneath with linear carinae, carinae on segments IV–VIII longer than those on segments IX–XI ( Fig. 2 ); segment III about 2 ×, segment IV about 1.3 ×, segment XII about 1.1 × as long as wide apically, respectively. Lower frons with deep depression, upper frons with dense, fine punctures, and with slender, longitudinal ridges; ocellar area moderately elevated, with very fine, contiguous punctures; vertex flat, vertex and gena with very dense, slender, transverse ridges. HW: HLD: HLF = 73: 29: 59; POD: OOD: OCD = 11: 13: 11.

Mesoscutum alutaceous, with sparse micro-punctures. Scutellum with fine, sparse punctures. Metanotum with dense, slender, irregular rugae. Mesopleuron alutaceous, with contiguous, slender, longitudinal rugae. Propodeal enclosure not delimited by carina, with shallow depression; dorsum and posterior surface of propodeum with dense, slender, longitudinal, regular rugae; lateral surface of propodeum with slender, longitudinal, irregular ridges. First recurrent vein of forewing ending in second submarginal cell, or interstitial between first and second submarginal cell; second recurrent vein ending in second submarginal cell. Legs normal, hind tibia with one row of yellowish spines on outer surface, spines slender, slightly longer than adjacent pubescence.

Dorsal surface of petiole moderately convex, with longitudinal carina medially; basal width of petiole, in dorsal view, nearly equal to its apical width ( Fig. 3 ); petiole with several slender longitudinal carinae on its apical half laterally; ventral surface of petiole flat, without keel. PL: PW: LTI: WTI: HFL: HTL = 32: 10: 40: 35: 45: 50. Hind trochanter not reaching end of petiole, hind femur far exceeding end of petiole. Gastral segments shiny, without punctures. Male genitalia ( Figs. 4, 5 ).

Female: Unknown.

Specimen examined: Holotype: ɗ, China: Tibet, Mangkang, Rongxi, 29°36'N 98°30'E, 27.vi.1976, coll. Yinheng Han.

Paratype. 3 ɗ, China: Tibet, Mangkang, Rongxi, 29°36'N 98°30'E, 27.vi.1976, coll. Yinheng Han; 2 ɗ, China: Tibet, Mangkang, 3800m, 29°36'N 98°30'E, 21.vi.1976, coll. Yinheng Han.

All type specimens are deposited in the Institute of Zoology, Chinese Academy of Sciences, Beijing, P. R. China.

Distribution: China: Tibet.

Etymology: The name, infossa , derived from the Latin infossa (= with depression), refers to the lower frons with a deep depression, which is one of the main recognition characters of this species.

Figures

FIGURES 1 – 5. Mimesa infossa Ma, Li and Chen, sp. nov. (Male). 1 Frontal view of head; 2 Lateral view of antennal segments III – XIII; 3 Dorsal view of gastral tergum I; 4, 5 Lateral view of male genitalia (scale line for figures 2 and 3: 1 mm; for 1: 1.18 mm; for 4 and 5: 1.82 mm).