Megachile (Callomegachile) impressa Friese, 1903

Chatthanabun, Nontawat, Ascher, John S., Pinkaew, Nantasak, Thanoosing, Chawatat, Traiyasut, Prapun & Warrit, Natapot, 2020, Resin bees of genus Megachile, subgenera Callomegachile and Carinula (Hymenoptera, Megachilidae) from Thailand with description of a new species, ZooKeys 997, pp. 95-144 : 95

Megachile (Callomegachile) impressa Friese, 1903 Figs 11 , 12

Megachile impressa Friese, 1903: 358. Male holotype (MFNB, not examined) Tenasserim (Kayin: Thandaung), Myanmar.

Diagnosis.

The species superficially resembles M. (Callomegachile) binghami Meade-Waldo, 1912, in terms of its overall appearance and size: black hairs on paraocular area; thorax with white hairs except central area of mesoscutum and scutellum; metasomal terga covered with ferruginous hairs; scopa ferruginous except white basal area; apical margin of clypeus with one medioapical tubercle and two lateral tubercles (Fig. 12b, c ); meso- and metatarsi with ferruginous hairs (Fig. 12a ). These characters are used to associate male and female bees.

Description.

Female. Length. Total body length 14.28-15.90; wingspan 23.40-26.54; fore wing 10.01-11.34. Structure and color. Head black; paraocular area with dense black hairs; central area of clypeus with strong median carina; apical margin of clypeus with medioapical tubercle and two lateral tubercles; subtriangular supraclypeal area with sparse punctures, apical and median area with strong carina; mandible with two stout apical teeth at apex and three small teeth basally, without cutting edge; outer surface of mandible minutely roughened with long black hairs; labrum rectangular, with surface minutely roughened and brimmed with erected long brown hairs along margins, conspicuously at apex; gena with sparse punctures; almost bare vertex with sparse punctures, ID shorter than OD, ID/OD = 0.50 ± 0.01; antennae with ten flagella, first flagellomere wider than long but shorter than the second; body parallel-sided, thorax covers with white hairs except central area of mesoscutum and scutellum; mesoscutum and lower part of mesepisternum with coarsely striate puncture pattern; procoxal base with conspicuous small carina, covered with sparse white hairs; pro- and mesotibiae with two spines at apices; metatarsus with one small spine at apex; protarsus covers with dense brown hairs; meso- and metatarsus cover with dense brown hairs on outer side, with dense ferruginous hairs inner side; wing brown with dark brown vein; T1 covers with sparse ferruginous hairs, with sparse punctures; T2-T5 cover with dense ferruginous hairs, dense punctures on pregradular area, sparse punctures on marginal zone; T6 covers with dense ferruginous hairs, with sparse punctures and round shape at apex; scopa ferruginous except the basal area with white.

Literature records.

Laos. Houaphan ( Ascher and Pickering 2020); Malaysia. Kelantan ( Ascher and Pickering 2020); Myanmar. Kayin, Tangdong, Tenasserim. ( Friese 1903; Ascher and Pickering 2020). Also recorded based on images on iNaturalist on two occasions from Huai Mae Priang, Kaeng Krachan District, Phetchaburi Province (credit: djhiker 2016; pam-piombino 2017).

Material examined.

Thailand. Chiang Mai Province: 1♀, Chom Thong district, Doi Inthanon Nat. P., Wildfire Control Station, 18°37'7.0590"N, 98°36'29.7606"E, Alt. 779 m, 20-VII-2015, coll. Warrit et al. (leg. NC and NW). Phitsanulok Province: 2♀, Phuhinrongkla Nat. P., 16°59'49.3008"N, 101°0'40.6772"E, Alt. 1303 m, 17-VI-2017, coll. N. Warrit et al. (leg. NC and NW).

Floral record.

Specimens from Phitsanulok province were collected on Craspedolobium unijugum (Gagnepain) Z. Wei & Pedley at Phuhinrongkla National Park along with M. umbripennis and Megachile (Creightonella) fraterna Smith, 1853.

Comments.

In the field, M. impressa can be confused with Megachile (Creightonella) fraterna since that species also has a black head and ferruginous hairs on abdomen. However, M. fraterna can be easily discriminated by characters in the mandible and cutting edge between interspaces.

Remarks.

Known sites for this species are in the highlands.

Figures

Figure 11. Thai distribution of Megachile (Callomegachile) impressa.

Figure 12. Megachile (Callomegachile) impressa Friese, 1903, female a lateral view b frontal view c clypeus and mandible d dorsal view of metasoma e lateral view of metasoma.