Scaptotrigona rosellae Engel, 2022

Engel, Michael S., 2022, Notes on South American stingless bees of the genus Scaptotrigona (Hymenoptera: Apidae), Part II: Subgroup A of the postica species group, Journal of Melittology 2022 (110), pp. 1-51 : 20-22

Scaptotrigona rosellae Engel , new species

ZooBank: urn:lsid:zoobank.org:act:115BA1F9-566A-43A4-B717-6130B3324BCD

( Figs. 26–28 )

DIAGNOSIS: This species is currently known only from the lower Anchicayá River Valley of Colombia, an area known for its considerable biodiversity and endemism. The species superficially resembles a lighter form of S. ederi but is immediately distinguished by the presence of a genal tooth, the presence of weak striping on the mesoscutum, and the generally yellow to fulvous bristles.

DESCRIPTION: As described for S. ederi (vide supra), with the following modifications: ⚲: Total body length approximately 6.1–6.2 mm, forewing length (to base of humeral sclerite) 6.0– 6.1 mm. Head wider than long, width 2.42–2.48 mm, length 1.97–2.03 mm; compound eye length 1.36–1.42 mm; upper interorbital distance 1.52–1.58 mm, lower interorbital distance 1.45–1.52 mm. Scape length 0.91 mm, about as long as torulocellar distance, torulocellar distance 0.88–0.91 mm. Clypeus approximately 1.7–1.8× as wide as long, length 0.64 mm, width 1.11–1.15 mm. Malar area approximately 1.8× flagellar diameter or 0.82× basal mandibular width. Preoccipital ridge carinate, lamellate dorsally, with bordering medial and lateral indentations deep, carina interrupted laterally by deep concavity, lower margin of concavity with carina forming acutely rounded angle projecting upward as a sharp, lamellate tooth, upper margin of concavity with lamella extending ventrally a third to half of concavity.

Integument of labiomaxillary complex yellow orange; labrum yellow orange; mandible yellow to reddish orange; clypeus yellow orange, epistomal sulcus well delineated by orange brown to brown; supraclypeal area yellow orange; malar space yellow orange; face below upper tangent of antennal toruli yellow orange; lower frons yellow orange blending to reddish orange to brown on upper frons, separated from inner and upper orbit by strip of yellow orange to reddish orange; vertex reddish brown to dark brown; ocellocular area reddish brown to dark brown except laterally where separated from upper orbit; posterior of head orange with strips of reddish brown to dark brown extending from ocellocular area to preoccipital carina, preoccipital carina dark brown to black; gena and postgena yellow orange to orange; scape yellow orange except sometimes with brown dorsoapically; pedicel and flagellum brown, with flagellum more orange ventrally. Mesosoma largely yellow orange to orange except mesoscutum black with reddish brown laterally and posteriorly, faint longitudinal strips of reddish brown from notauli to posterior border; mesepisternum with brown to dark brown patch ventrally; basal area and posterior surface of propodeum reddish brown to dark brown; metepisternum sometimes stained brown; tegula wholly yellow orange and semi-translucent; legs yellow orange. Metasoma generally brown to dark brown except anterior-facing surface of tergum I yellow orange, dorsal-facing disc of tergum I largely yellow orange with yellow brown laterally, sometimes lateral areas dark brown and more encroaching on yellow orange disc; tergum II largely yellow orange with small areas of brown laterally, although sometimes largely dark brown and blending to orange posteriorly before broad yellow marginal zone; terga III – IV brown to dark brown with broad yellow marginal zones, largely obscured by tomentum; sterna largely yellow orange to yellow brown.

As for S. ederi except areas of short, plumose setae yellow to pale yellow instead of white; metepisternum and lateral surface of propodeum obscured by dense, plumose, yellow setae; dorsal-facing surface of tergum I with largely simple setae. Bristles of vertex erect, simple, yellow to fulvous; pronotal dorsolateral margin near and anterior to pronotal lobe with long, arched, yellow bristles; mesoscutum anterior and lateral borders with erect bristles, those on lateral border short, anterior margin with largely fulvous bristles, sometimes intermixed with yellow to dark fulvous bristles; tegula with short, suberect, yellow bristles anteriorly; mesoscutellum with abundant, elongate, erect bristles posteriorly, such bristles minutely pectinate apically, discal bristles shorter, mesoscutellar bristles yellow to fulvous; mesepisternal bristles as in S. ederi except yellow to fulvous. Legs with abundant bristles, bristles typically yellow to fulvous except sometimes noticeably intermixed with fuscous to black bristles on prolateral surface of mesotibia apically, prolateral surface of mesobasitarsus, metafemur at extreme apex; corbicular bristles fuscous to black, marginal bristles intermixed with some yellow to fulvous bristles; prolateral surface of metabasitarsus with scatered fine, simple, yellow setae (noticeably thinner than marginal bristles), but without black setae, margins with black bristles intermixed with yellow to fulvous bristles; penicillum dark fulvous to fuscous; rastellum fulvous. Metasoma with numerous, subdecumbent, yellow bristles on terga III – V arising from tomentum, similar bristles sparser on tergum II.

♀: Latet.

♂: Latet.

HOLOTYPE: ⚲, Colombia: Prov. Valle, Rio Anchicaya , 400 m, 11 Feb. 1977, M.D. Breed & C.D. Michener ( SEMC).

PARATYPE: ⚲, Colombia: Prov. Valle, Rio Anchicaya , 400 m, 10 Feb. 1977, M.D. Breed & C.D. Michener ( SEMC) .

ETYMOLOGY: The specific epithet honors my goddaughter, Ms. Rosella Amparo Betancourt, a brilliant young poet and budding scholar.

Figures

Figures 26–28. Worker of Scaptotrigona rosellae, new species. 26. Lateral habitus. 27. Facial view. 28. Dorsal view of vertex and mesosoma.