Habropoda tumidifrons Lieftinck, 1974

Tran, Ngat Thi, Engel, & Michael S., 2025, A contribution to the knowledge of Habropoda from Vietnam (Hymenoptera: Apidae), Raffles Bulletin of Zoology 73, pp. 125-152 : 143-147

Habropoda tumidifrons Lieftinck, 1974

( Figs. 15–18 )

Habropoda tumidifrons Lieftinck, 1974: 182 .

Material examined. VIETNAM: 2 females, 3 males, Cao B ằng Province, Nguyên Bình District, Quang Thành Commune , Hoài Khao Village , 22°36ʹ57ʺN, 105°56ʹ59ʺE, alt. 628 m, coll. Liên Th ị PhƯƠng Nguy ễn, Ngát Th ị Tr ần, CƯờng Quang Nguy ễn, 10.v.2021 [1 female, 2 males in IEBR, 1 female, 1 male in AMNH] ; 2 females, Cao B ằng Province, Nguyên Bình District, Thành Công Commune , Phia Oắc – Phia Đén National Park , 22°34ʹ18ʺN, 105°52ʹ34ʺE, alt. 1052 m, coll. Ngát Th ị Tr ần, 24.vii.2024 ; 3 females, Cao B ằng Province, H ạ Lang District, Đ ức Quang Commune , 22°45ʹ39ʺN, 106°37ʹ36ʺE, alt. 517 m, coll. Liên Th ị PhƯƠng Nguy ễn, Ngát Th ị Tr ần, CƯờng Quang Nguy ễn, 19.v.2023 ; 2 females, Tuyên Quang Province, Hàm Yên District, Yên Thu ận Commune , Cao ĐƯ ờng Village , Chạm Chu Natural Reserve , 22°20′16.4″N, 103°51′09.4″E, alt. 670 m, coll. Lam Xuân TrƯƠng, Liên Th ị PhƯƠng Nguy ễn, CƯờng Quang Nguy ễn, Ngát Th ị Tr ần, Thái Văn Mai, 12.v.2019 ; 8 females, Tuyên Quang Province, Hàm Yên District, Yên Thu ận Commune , Cao ĐƯ ờng Village , Chạm Chu Natural Reserve , road to the top, 22°17′26.6″N, 104°59′09.7″E, alt. 695 m, coll. Lam Xuân TrƯƠng, CƯờng Quang Nguy ễn, Ngát Th ị Tr ần, Thái Văn Mai, 13.v.2019 ; 1 female, Tuyên Quang Province, Hàm Yên District, Yên Thu ận Commune , Cao ĐƯ ờng Village , Chạm Chu Natural Reserve , way to waterfall, 22°17′32.5″N, 104°59′28″E, alt. 643 m, coll. Lam Xuân TrƯƠng, CƯờng Quang Nguy ễn, Thái Văn Mai, 15.v.2019 ; 2 females, 22°17′32.5″N, 104°59′28″E, alt. 643 m, coll. Liên Thị PhƯƠng Nguyễn, CƯờng Quang Nguyễn, 16.v.2019; 9 females, 1 male, Tuyên Quang Province, Hàm Yên District, Yên Thu ận Commune , Cao ĐƯ ờng Village , Chạm Chu Natural Reserve , 22°17′08.6″N, 104°59′27.4″E, alt. 691 m, coll. Lam Xuân TrƯƠng, Ngát Th ị Tr ần, Thái Văn Mai, 16.v.2019 [ IEBR].

Diagnosis. In both sexes, body robust; clypeus convex in profile, labrum subrectangular and with minute medio-apical emargination; mesosoma uniformly covered with dense, long, ochraceous-orange setae; metasomal terga I covered by ochraceous-orange setae; apical margin of terga I–III with thin linear, ochraceous-orange setal bands. In females, clypeus with inverted T-shaped yellow to chrome-yellow maculation medially; pygidial plate with lateral margins gradually narrowed to basal half, then slender on the remaining part and apex nearly rounded. In general, male gonostylus similar to that of H. pierwolae except the dorsal process not so expanded apically; sternum VII narrowed near midlength, apical disc hexagon-shaped, apical margin concavely emarginate medially, dense setae laterally and apically; sternum VIII expanded horizontally, round apically, with dense setae medio-apically.

Description (hitherto undescribed). Male: Total body length 11.5–12 mm, forewing length 8.5–9 mm. Body robust. Head broader than long, approximately 1.6× as broad as long ( Fig. 17A ). Compound eyes large and bulging ( Fig. 17A ). Mandible bidentate, preapical tooth extremely short, apical tooth long and slightly pointed apically ( Fig. 17B ). Clypeus convex, approximately 1.6× as broad as long. Supraclypeal area slightly convex ( Figs. 15C , 17A ). Labrum broader than long, approximately 1.7× as long as broad, shiny tubercles baso-laterally, with minute emargination medio-apically ( Fig. 17B ). Scape rather short, approximately 2.6× as long as broad, flagellomere I longer than broad, flagellomere I 1.1× length of flagellomere II; flagellomeres III–X subequal in lengths and longer than flagellomere II; flagellomere XI longest flagellomere ( Fig. 17C ). Sterna IV–VI as in Fig. 18A–C . Sternum VII narrowed near midlength, apical disc hexagon-shaped, apical margin concavely emarginate medially, dense setae laterally and apically ( Fig. 18D ); sternum VIII expanded horizontally, round apically, with dense setae medio-apically ( Fig. 18E ). Male gonostylus with the dorsal process relatively slender, apically little expanded with a setal tuft, and the ventral process plate-shaped, apical margin nearly straight with abundant setae on mesal corner. ( Fig. 18F, G ).

Clypeus shiny, with small, shallow, sparse, wrinkled punctures, punctures separated by 1–3× puncture width except dense, coarser punctures laterally ( Fig. 17A ). Labrum mostly with dense, contiguous, wrinkled punctures, basolateral tubercles smooth and shiny. Mandible with small, sparse punctures half basally and shiny, smooth, impunctate on remainder ( Fig. 17B ). Paraocular area, supraclypeal area, frons, vertex with coarse, dense punctures. Mesoscutum, mesoscutellum with round, dense, near contiguous punctures. Metasomal terga with round, dense punctures separated by 0.5–1× puncture width, size of punctures smaller than those on mesoscutum ( Fig. 17E, F ).

Clypeus yellow except black apico-laterally and drop-shaped mark baso-laterally, with brownish red apical margin ( Fig. 17A ). Labrum dark yellow except brownish red baso-laterally, laterally, and apically ( Fig. 17B ). Basal half of mandible yellow, then brownish red to brownish black ( Fig. 17B ). Labiomaxillary complex ferruginous ( Fig. 15C ). Flagellomeres II–XI dark brownish red ventrally ( Fig. 17C ). Legs largely dark brownish red to brownish red, claws black. Sterna apically brownish red.

Setae on body plumose except for simple setae mostly found on clypeus and labrum. Clypeus with some short, sparse, yellow setae except short, ochraceous-orange setae mixed some long, black plumose setae laterally ( Fig. 17A ). Labrum with yellow setae, setae longer and denser than those on clypeus. Mandible with long, yellowish setae half baso-ventrally ( Fig. 17B ). Paraocular area with short, yellowish orange setae from base to below antenna socket and the remaining part of paraocular area, supraclypeal area and scape with short, dense, ochraceous-orange setae. Frons, the inner space between and laterally of ocellus with long, ochraceous-orange setae mixed black setal tufts ( Fig. 17A ). Gena from base to half-length of compound eyes with long, dense, white setae, then to the top of compound eyes with dense, ochraceous-orange setae ( Fig. 15C ). Mesosoma with abundant, ochraceous-orange setae mixed some black setae dorsally; setal colour paler laterally and ventrally ( Fig. 15C ). Setae on metasomal terga similar to female except terga VI–VII apically with black setal bands ( Fig. 17E ). Ventral surface of profemur and mesofemur with long, dense, pale ochraceous-orange setae. Outer surface of protibia, probasitarsus, mesotibia, and mesobasitarsus with short, dense ochraceous-orange setae; retrolateral surface of metabasitarsus with stiff, ochraceous-orange setae. Prolateral surface of metatibia with brownish black setae. Sternum IV with near straight apically and with long, blackish setae latero-apically; sternum V slightly concave apically and with long, blackish setae latero-apically; sternum VI with short, blackish setae apico-laterally ( Fig. 18A–C ).

Distribution. Vietnam (Northern and Central Highlands).

Remarks. H. tumidifrons has been recorded in the Central Highlands, Vietnam (Lam Dong province). This species is most similar in the Vietnamese fauna to H. pierwolae owing to the form of the body and shape of the male gonostylus, but can be separated from the latter based on the following: 1) in both sexes, clypeus gently convex in profile (clypeus profile strongly convex in H. pierwolae ), 2) in females, apical margins of terga I–III with thin linear, ochraceous-orange setal bands and of tergum IV with black setal band (apical margins of terga I–IV with thick, uniform, bright yellow setal bands in H. pierwolae ), 3) sternum VII of males narrowed near midlength, apical disc hexagon-shaped (sternum VII of males not expanded medially nor hatchet-shaped, tapering slightly from midlength to apical margin with broad medioapical lobe in H. pierwolae ); 4) sternum VIII of males expanded horizontally, round apically (sternum VIII of males with lateral margins of disc almost straight, converging to apical margin with broad medial concavity between to apical angles, concavity with minute, bluntly rounded lobe in H. pierwolae ), and 5) the dorsal process of male gonostylus slightly expanded apically (the dorsal process of male gonostylus much expanded apically in H. pierwolae ). This species was described by Lieftinck (1974) based on a unique female collected in the Central Highlands of Vietnam (Lam Dong Province). The present paper describes the male of H. tumidifrons for the first time.

Floral association. This species was collected at flowers of Rubus multibracteatus Levl. and Rubus pyrifolius Sm. ( Rosaceae : Rosoideae ) ( Fig. 20E, F ).

Nesting biology. In Cham Chu Natural Reserve (Tuyen Quang Province), six nests were found within an area of about 3 m 2 and were constructed into the soil (in some areas with a layer of moss) floor of a stilt house ( Fig. 19D ). The nests were only observed during the earliest stages of the nest building process, with nest entrance diameter and nest length of about 1.5 cm and 15 cm, respectively ( Fig. 19C ). During the nesting process, the bees’ excavation produced small humus particles around the nest entrance ( Fig. 19A ). In Quang Thanh Commune (Cao Bang Province), four nests were found on the ground of an abandoned house, and were also only early in development.

Figures

Fig. 15. A–D, Habropoda tumidifrons Lieftinck, 1974, female and male; A, lateral habitus, female; B, dorsal habitus, female; C, lateral habitus, male; D, dorsal habitus, male. Scale bars = 1.0 mm.

Fig. 16. A–G, Habropoda tumidifrons Lieftinck, 1974, female; A, head, frontal view; B, labrum and mandible, frontal view; C, left antenna; D, head and mesosoma, dorsal view; E, left wing; F, metasoma, dorsal view; G, pygidial plate, dorsal view. Scale bars = 1.0 mm (A, C–F), 0.5 mm (B, G).

Fig. 17. A–E, Habropoda tumidifrons Lieftinck, 1974, male; A, head, frontal view; B, labrum and mandible, frontal view; C, left antenna; D, head and mesosoma, dorsal view; E, metasoma, dorsal view; F, metasomal terga V–VII, dorsal view. Scale bars = 1.0 mm (A, C–E), 0.5 mm (B, F).

Fig. 18. A–G, Habropoda tumidifrons Lieftinck, 1974, male; A, metasomal sternum IV; B, metasomal sternum V; C, metasomal sternum VI; D, metasomal sternum VII; E, metasomal sternum VIII; F, genitalia, dorsal view; G, genitalia, ventral view. Scale bars = 1.0 mm (A, B), 0.5 mm (C–G).

Fig. 20. A–F, Floral associations of Vietnamese Habropoda species in Vietnam; A, flowers of Rubus alceifolius Poir. (family Rosaceae), at which females of H. mimetica disconota were collected; B, flowers of Rubus sp., at which males of H. mimetica disconota were found; C, flowers of Pogostemon cablin (Blanco) Benth. (family Lamiaceae), at which females of H. sutepensis were collected; D, flowers of Hedyotis capitellata Wall. ex G. Don (family Rubiaceae), at which males of H. sutepensis were found; E, F, flowers of Rubus multibracteatus Levl. and Rubus pyrifolius Sm. (family Rosaceae), respectively, at which females of H. tumidifrons were found.

Fig. 19. A–D, Nest and habitat of Habropoda tumidifrons Lieftinck, 1974; A, nest entrance in outside view; B, entry activity; C, inside of the nest (the rightmost piece is the end of the tunnel, the two remaining pieces are the sides of the tunnel); D, habitat where the nests were found, red rectangle indicates area where nests were found.