Megachile (Litomegachile) pankus, Bzdyk, Emily L., 2012

Bzdyk, Emily L., 2012, A revision of the Megachile subgenus Litomegachile Mitchell with an illustrated key and description of a new species (Hymenoptera, Megachilidae, Megachilini), ZooKeys 221, pp. 31-61 : 46-48

Megachile (Litomegachile) pankus sp. n.

Type material.

Holotype female: MEXICO: Hidalgo, Pachuca, 11 Jun 1935, R. M. and G. E. Bohart (BBSL). Paratypes: 1 female: MEXICO: Sonora, Alamos, 4 Sep 1991 (AMNH), 1 female: MEXICO: Sinaloa, Mazatlan 28 Oct 1969 (BBSL); 1 female: MEXICO: Sinaloa, 4 mi NW Choix, 31 Aug 1968 (BMEC); 1 female: MEXICO: Sinaloa, 6 mi NW Choix, 6 Aug 1968 (BMEC).

Diagnosis.

Megachile pankus is unique among Litomegachile species because the female has a mandible with an angulation between teeth 3 and 4, and T6 is basally convex and apically concave. No other species in the subgenus has this combination of characters. The female Megachile onobrychidis has similar metasomal features, but has more black setae on S6, while Megachile pankus has only a few black setae on T6. It can also be further distinguished from Megachile onobrychidis and Megachile brevis by the angulation between teeth 3 and 4 of the mandible. T6 is convex basally and concave apically in profile, and concave laterally in dorsal view, which distinguishes it from Megachile mendica or Megachile gentilis .

Female description.

Body length 10 mm. Forewing length 7 mm. Head: HL 0.7 × HW; compound eyes convergent below, with upper inner margins slightly convergent above; lateral ocelli closer to margin of vertex than edge of compound eye; compound eye width 1.1 × width of genal area in lateral view; clypeus twice as wide as high (Figure 3B); clypeus and supraclypeal area slightly convex; punctation fine, with larger punctures on clypeus, becoming smaller on supraclypeal, paraocular area, vertex and rest of head; punctures never separated by more than 0.3 × puncture diameter; labrum width 0.8 × length; AD 3 × width of antennal socket, ID 0.6 × ASO; ID 1.36 × length of scape; mandible with recessed cutting edges between teeth 3 and 4 and incomplete recessed cutting edge that forms rough right angle between teeth 3 and 2; surface between teeth 3 and 4 angulate (Figure 2C, 4B); scape length 4.3 × width, with white setae; pedicel and F1 width 0.8 × length; pedicel length 0.8 × F1; F2-6 length equal to width; F7-8 length 0.9 × width; F9 length 0.8 × width; F10 length 0.7 × width; Mesosoma: mesepisternum convex, large and pronounced, twice as wide as pronotum; scutum length 0.8 × width; scutellum length 0.3 × scutum length, scutellum width 0.4 × scutellum length; tegula twice as long as wide; scutum 7.2 × width of tegula. Wings: forewing length 2.7 × width; WCL 0.8 × length of wing; SL 0.2 × MCL; with two submarginal cells, first submar ginal crossvein angled parallel to medial vein, second submarginal crossvein angulate; distance from distal edge of stigma to wing base 0.7 × distance from wing base to distal edge of marginal cell; hindwing with jugal lobe that does not extend past cubital cell; LTJ 0.3 × HWL; LTV 0.5 × HWL (Figure 3A). Legs: ratio of segment length of foreleg (compared to FL): CL 0.6 ×, TL 0.3 ×, FL 1 ×, TBL 0.9 ×, TRL 1.2 ×, BTL 0.5 ×, DTL 0.3 ×; foreleg with tibial spur modified as antennal cleaner, TSL 0.2 ×; midleg segment ratios: CL 0.7 ×, TL 0.4 ×, FL 1 ×, TBL 1 ×, TRL 1.3 ×, BTL 0.7 ×, DTL 0.3 ×; foreleg with tibial spur, TSL 0.3 × TBL; hindleg segment ratios: CL 0.5 ×, TL 0.3 ×, FL 1 ×, TBL 0.9 ×, TRL 1.4 ×, BTL 0.7 ×, DTL 0.3 ×; tibia with two spurs, TSL 0.4 × TBL; hindleg with basitarsus dilated 4.5 × width of distitarsus (Figure 3C). Metasoma: T2-4 with shallow transverse basal grooves; T1-5 with apical fringes of white hair covering marginal zone, T1-2 fringe widths 0.2 × width of discal surface medially, T3-5 fringe widths 0.3a width of discal surface medially; T1-2 apical fringes of white hair more sparse, marginal zone slightly visible between hairs; T1-5 with white discal pubescence; T6 discal surface with black appressed pubescence and black erect setae; T6 convex basally and concave apically in profile, and concave laterally in dorsal view;S1-5 with yellow setae; S6 with yellow setae and some black setae apically (Figure 5F). Color: Body black, legs brownish distally, wing membrane slightly tinted brown, veins brown (Figure 2A-B). Pubescence: White on head except ocellar region black; paraocular area, supraclypeal area and clypeus with dense pubescence obscuring view of integument; vertex with sparse pubescence with integument visible beneath; genal area with pubescence sparse beginning at dorsal surface, progressively more dense toward malar area. Mesosomal pubescence white; dense around tegula and behind scutellum, sparse on scutum, dense on ventral mesosomal surface.

Male.

unknown

Etymology.

The species name ‘pankus’ is a nonsense combination.

Distribution.

Megachile pankus has only been collected in Mexico (Figure 14).

Flower records.

Petalostemon sp. ( Fabaceae ).