Microsphecodes dominicanus (Stage, 1972)

Gibbs, Jason, 2016, Bees of the family Halictidae Thomson, 1869 from Dominica, Lesser Antilles (Hymenoptera: Apoidea), European Journal of Taxonomy 180, pp. 1-50 : 31-34

Microsphecodes dominicanus (Stage, 1972)

Figs 15 A–C, 16A–C

Sphecodes (Microsphecodes) dominicanus Stage in Eickwort & Stage, 1972: 509 , figs 17–27.

Type locality

DOMINICA: S Chiltern, 1600 ft., 19 Feb. 1965, coll. H.E. Evans (holotype, Ƌ, NMNH).

Material examined

Type material

DOMINICA: 1 Ƌ, paratype, St. Joseph Parish, Clarke Hall, Layou Valley, 4–7 Feb. 1965, coll. H.E. Evans ( NMNH); 1 Ƌ, paratype, Clarke Hall, Layou Valley, 2–13 Mar. 1965, coll. H.E. Evans ( NMNH).

Other material

DOMINICA: 1 ♀, St. Paul Parish, ATR[E]C, Springfield, Fifi Trail, ‘site 2’, 15°21’ N, 61°22’ W, 442 m, 24 May–4 Jun. 2003, coll. T. Decker & W. Wells, Malaise trap, voucher #645 ( TAMUIC).

Description

Female

MEASUREMENTS (n = 1). Length 3.4 mm; head length 0.9 mm; head width 1.1 mm; intertegular distance 0.6 mm.

COLOURATION. Head blackish-brown, except clypeal distal margin, labrum, mandible and anterior surface of scape testaceous. Flagellum dark reddish brown. Mesosoma including tegula and legs testaceous, except mesonotum reddish orange, mesoscutellum with dark brown patch. Wing membrane faintly dusky, with dark setae, venation and pterostigma dark brown. Metasoma testaceous, except apex of T1–T4 reddish orange, T5–T6 and apex of T4 dark brown.

PUBESCENCE. Dull white. Sparse erect setae throughout. Subappressed tomentum on face below eye emargination. Mesofemur and mesotibia without pollen brush. Metafemur without scopa. Metatibia with thick setae on dorsal edge. Penicillis absent. Metasomal sterna without scopa.

SURFACE SCULPTURE. Face polished, punctation fine. Clypeus punctation dense (i = 1–1.5 pd). Supraclypeal area, lower and upper paraocular areas and frons densely punctate (i ± pd). Ocellocular area punctate (i ± pd). Postgena weakly imbricate, gena finely punctate-lineolate. Mesoscutum polished; punctation moderately coarse, relatively dense laterad of parapsidal lines (i = 1–1.5 pd), sparser on posterior and medial area of disc (i = 1–3 pd); mesoscutellum similar. Metanotum rugulose. Preëpisternum reticulate rugulose. Hypoepimeral area finely punctate. Mesepisternum below scrobe finely rugulose, ventral half smooth. Metepisternum with longitudinal carinulae. Metapostnotum reticulate-rugose. Propodeum posterior and lateral surfaces reticulate rugulose. T1–T6 polished, T3–T5 weakly coriarious basally. Metasomal sterna coriarious and finely, sparsely punctate (i = 2–4 pd).

STRUCTURE. Head wide (length/width ratio = 0.8). Eyes weakly convergent below. Labrum broad, without apical projection or dorsal keel. Clypeus ½ below suborbital tangent. Mandible simple, without preapical tooth. Gena narrower than eye. Hypostomal carinae diverging towards mandible. F1 much broader than long, shorter than pedicel. Pronotal dorsolateral angle acute. Pronotal ridge carinate, interrupted by sulcus. Tegula ovoid. Submarginal cells three (1rs-m present), 2 nd submarginal cell narrow, posterior length slightly less than anterior length of 3 rd submarginal cell. Distal hamuli arranged 2-2. Inner metatibial spur minutely serrate. Legs slender. Basitibial absent. Metatarsus 2 narrow at base, length as long as metatarsus 3. Propodeum with lateral carina, reaching ½ distance to dorsal margin; oblique carina fine. T5 without evident pseudopygidial area, T6 with narrow pygidial plate.

Remarks

The female of Microsphecodes dominicanus is described above for the first time. Both sexes can be distinguished easily from the two Sphecodes described above by the presence of yellow-testaceous colour on the legs and mesosoma ( Figs 15B , 16B ) and the reticulate rugae present on the metapostnotum and posterior propodeal surface ( Figs 15C , 16C ; see also Eickwort & Stage 1972: figs 17–18). The host of M. dominicanus is unknown, but Microsphecodes are known to parasitize both Habralictus and Lasioglossum ( Michener 1978; Michener et al. 1979). The single female specimen was collected at the same site as were seven specimens of H. gonzalezi and a single specimen of L. kalinago sp. nov., but L. dominicense sp. nov. is also known from nearby sites.

The use of Microsphecodes at the generic level is questionable. Sphecodes (Austrosphecodes) is evidently rendered paraphyletic by Microsphecodes based on molecular phylogenetic results ( Habermannová et al. 2013). The implication of these results is that some or all Austrosphecodes should be synonymized with Microsphecodes . The latter name has priority, but if Austrosphecodes is treated at only the subgeneric level, then Microsphecodes should also be treated as a subgenus of Sphecodes . The current phylogenetic hypothesis would allow for Austrosphecodes and Microsphecodes combined to be treated at the generic level since together they form the sister group to other species included in the phylogeny ( Habermannová et al. 2013). Full taxon sampling of major sphecodine groups has not been completed. The West Indian genus Nesosphecodes Engel, 2006 , for example, also needs to be included in future studies of sphecodine bees. Until a more complete revision of the higher level systematics of the Sphecodini is completed, Microsphecodes is used as a genus following current usage ( Michener 2007) despite the apparent synonymy.

Tribe Caenohalictini Michener, 1954

Genus Habralictus Moure, 1941

Habralictus Moure, 1941: 59 (type species: Habralictus flavopictus Moure, 1941 , by original designation).

Zikaniella Moure, 1941: 57 (type species: Zikaniella crassiceps Moure, 1941 , by original designation).

Figures

Fig. 15. Microsphecodes dominicanus (Stage, 1972), ♀. A. Face. B. Lateral habitus. C. Dorsum of mesosoma. Scale bars = 1 mm.

Fig. 16. Microsphecodes dominicanus (Stage, 1972). Paratype, Ƌ. A. Face. B. Lateral habitus. C. Dorsum of mesosoma. Scale bars = 1 mm.