Anthidiellum (Pycnanthidium) coronum (Wu, 2004)

Tran, Ngat Thi, Engel, Michael S., Nguyen, Cuong Quang, Tran, Duong Dinh & Nguyen, Lien Thi Phuong, 2023, The bee genus Anthidiellum in Vietnam: descriptions of five new species and the first male of Anthidiellum coronum (Hymenoptera, Megachilidae), ZooKeys 1144, pp. 171-196 : 171

Anthidiellum (Pycnanthidium) coronum (Wu, 2004)

Figs 8A-H , 9A-G , 10A, B

Trachusa (Paraanthidium) coronum Wu, 2004: 545 [holotype ♀]; Wu 2006: 177.

Anthidiellum (Pycnanthidium) coronum (Wu); Niu et al. 2016: 337.

Material examined.

Vietnam: 1♂, Gia Lai, Mang Yang, Ayun , Kon Ka Kinh NP, 14°12'11"N, 108°18'58"E, alt. 834 m, 25.iii.2022 [25 March 2022], Lien Thi Phuong Nguyen, Ngat Thi Tran, Cuong Quang Nguyen leg. [IEBR] ; 3♀♀ 2♂♂, Gia Lai, Mang Yang, Ayun , Kon Ka Kinh NP, 14°12'11"N, 108°18'58"E, alt. 834 m, 26.iv.2022 [26 April 2022], Lien Thi Phuong Nguyen, Ngat Thi Tran leg. [2♀♀ 2♂ in IEBR, 1♀ in AMNH] ; 1♂, Gia Lai, Mang Yang, Ayun , Kon Ka Kinh NP, 14°12'11"N, 108°18'58"E, alt. 834 m, 27.iv.2022 [27 April 2022], Lien Thi Phuong Nguyen, Ngat Thi Tran leg. [AMNH]

Description

(hitherto undescribed). ♂: body length 7.0 mm, forewing length 6.0 mm.

Structure. Head broader than long, about 1.2 × as broad as long (Fig. 9C ). Compound eyes about 2.1 × as long as broad, about 1.7 × genal width. Mandible tridentate, first two teeth short, subequal in length, third tooth longest (Fig. 9C ). Clypeus flat, about 1.8 × as broad as long. Supraclypeal area slightly convex. Antennal scape short, about 3 × as long as broad, pedicel about 1.3 × as broad as long and subequal in length of F1, F1 short, broader than long and approximately 0.6 × length of F2, F2-F9 subequal in length, F10 longest flagellomere, about 2.2 × as long as broad. Mesoscutum approximately 1.2 × as broad as long; mesoscutellum slightly convex, with mediolongitudinal depression apically (Fig. 9B ). Forewing with two submarginal cells, first submarginal cell broader than second submarginal cell. Metatibia and metabasitarsi enlarged (Fig. 9F ); metapretarsal arolium present (Fig. 9G ). Anterior surface of metasomal T1 concave; T7 with a short spine medially; apical margin of S5 with comb of stiff, black, peg-like setae (Fig. 9E ). Male genitalia with gonostylus forked into two unequal branches, inner branch long, swollen, lateral margins curved, outer branch shorter, slender, nearly straight (Fig. 10A, B ).

Sculpturing and texture. Mandible from base with sparse, faint, wrinkled punctures except small punctures apically. Clypeus, supraclypeal area, and paraocular area from base to above tangent above antennal toruli with shallow, wrinkled punctures. Frons with coarse, dense punctures. Vertex with round, dense punctures, punctures larger than those on frons. Mesoscutum with round, dense punctures, punctures larger than those on vertex; mesoscutellum with dense, wrinkled punctures (Fig. 9D ). Metasomal T1-T2 with small, round punctures; T3-T5 with sparse punctures basally and dense punctures on remainder of terga; T6 with shallow, dense punctures.

Color. Body black except as follows: clypeus yellow except yellow brown transparent on apical margin; mandible yellow except brownish black on apically; paraocular area with yellow marking extending along the inner margin to above the antennal socket; supraclypeal area with yellow marking as Fig. 8C ; antennal space apico-ventrally with small yellow marking; gena with yellow markings extending from the two-third of the eye to exceed the top of eye (Fig. 9C ). Pronotal lobe yellow, except yellow transparent in apical margin and a yellow brown transparent spot on the median area; in dorsal view, mesoscutum lateral margin with thin, short, paint yellow markings (or absent in some specimens); tegula basally with yellow markings; mesoscutellum with yellow marking and interrupted on apico-medially, apical margin of yellow to yellow to yellow transparent marking; axilla black (or with small, yellow spot in some specimens) (Fig. 9D ). Profemur latero-apical with small yellow markings; outer surface of protibia and mesotibia with thin, yellow marking, posterior and apical margins of metatibia with yellow marking and presence of two small brown marks embedded on yellow marking apically; all basitarsus yellow, tarsi dull tawny yellow. Metasomal T1-T2 laterally with small yellow markings, T3 basally with yellow band and interrupted medially, T4-T5 basally with yellow bands, T6-T7 with yellow, except baso-laterally (Fig. 9A, B ).

Pubescence. Clypeus with some short, yellowish setae on apical margin; paraocular area and supraclypeal area with some sparse, short, yellowish setae; scape with short yellowish setae; face above antennal torulus and frons with tufts of long, white, plumose setae (Fig. 9C ); vertex with sparse, short, yellowish setae. Margins of mandible with short, yellowish setae intermixed with some longer setae. Mesoscutum and mesoscutellum with short yellowish setae. Propodeum with dense, long, plumose, white setae. Prolateral surfaces of metabasitarsus and metatarsus with dense, erect, white setae; retrolateral surfaces of these same podites with tawny yellow setae. Metasomal S3 medio-apical margin with tuft of long, tawny yellow setae; surface of S6 with long, yellowish setae and apical margin of S6 with long, yellowish, plumose setae.

Figures

Figure 8. Anthidiellum (Pycnanthidium) coronum (Wu, 2004), female A lateral habitus B dorsal habitus C facial view D mandibles E mesosoma in dorsal view F dorsal oblique view of metasoma G prolateral surfaces of metatibia and metatarsus H metatarsus and metapretarsus, red arrow indicating arolium. Scale bars: 1 mm (A-C, E, F); 0.5 mm (D, G, H).

Figure 9. Anthidiellum (Pycnanthidium) coronum (Wu, 2004), male A lateral habitus B dorsal habitus C facial view D mesosoma in dorsal view E metasomal apex in ventral view, red arrow indicating thick peg-like and scale-like setae F prolateral surfaces of metatibia and metatarsus G metadistitarsus and metapretarsus, red arrow indicating arolium. Scale bars: 1 mm (A, B, D, F); 0.5 mm (C, E, G).

Figure 10. Male genitalia of two Vietnamese species of Anthidiellum Cockerell (Anthidiini) (dorsal views at left, ventral views at right) A, B Anthidiellum (Pycnanthidium) coronum (Wu, 2004) C, D A. (P.) cornu Tran, Engel & Nguyen, sp. nov. Scale bars: 0.5 mm.