Scaptotrigona santiago 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 : 42-43

Scaptotrigona santiago Engel , new species

ZooBank: urn:lsid:zoobank.org:act:B250EC5E-B712-4D57-850A-EE821FEFE6BE

( Fig. 58 )

DIAGNOSIS: This is another species lacking a genal tooth and similar to S. ederi in its overall darker coloration. It can be distinguished from S. ederi by the wholly brown genae ( Fig. 58 ) and the uniquely bicolored bristles of the mesoscutum and corbicula, where the majority of the rachis is black before blending to off white apically.

DESCRIPTION: As described for S. ederi (vide supra), with the following modifications: ⚲: Total body length approximately 6.1 mm, forewing length (to base of humeral sclerite) 6.1 mm. Head wider than long, width 2.42 mm, length 1.94 mm; compound eye length 1.39 mm; upper interorbital distance 1.52 mm, lower interorbital distance 1.42 mm. Scape length 0.91 mm, about as long as torulocellar distance, torulocellar distance 0.88 mm. Clypeus approximately 1.6× as wide as long, length 0.67 mm, width 1.06 mm. Malar area approximately 1.8× flagellar diameter or 0.80× 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 rounded angle, without sharply acute lamellate tooth.

Integument of labiomaxillary complex orange; labrum yellow; mandible orange; clypeus largely yellow orange with stains of orange paramedially, epistomal sulcus delineated yellow orange; supraclypeal area orange; malar space yellow; face below tangent of antennal toruli yellow; scape yellow to yellow orange below, brown dorsally; pedicel and flagellum brown, with narrow underside of flagellum orange; face above antennal toruli brown, vertex, ocellocular, and posterior of head as on upper frons; gena and postgena as on upper frons except area immediately bordering malar space yellow orange to orange. Mesosoma largely dark brown to black except mesoscutellum, metanotum, and basal area and posterior surface of propodeum yellow; tegula brownish orange and semi-translucent; legs largely dark brown except coxae and trochanters orange, apices of femora and tibiae orange including corbicular surface, and apical tarsomeres orange. Wing membranes parchment colored; veins orange. Metasoma generally dark brown except anterior-facing surface of tergum I brown, dorsal-facing disc of tergum I yellow posteriorly; tergum II yellow posteriorly; terga III – V dark brown with yellow apical marginal zones; tergum VI dark brown; sterna brown to dark brown.

Vertex with numerous erect, simple, fuscous bristles, typically with off white tips, some bristles near upper orbits black; pronotal dorsolateral margin near and anterior to pronotal lobe with yellow to dark fuscous bristles; mesoscutum anterior and lateral borders with fuscous bristles, typically with off white tips; tegula with suberect fuscous bristles anteriorly; mesoscutellum with abundant, elongate, erect fuscous to dark fulvous bristles; mesepisternum with scatered, erect to subdecumbent pale yellow to off white bristles, longer ventrally, along rounded anterior border with preëpisternum a line of abundant, suberect to subdecumbent fuscous bristles with off white tips extending ventrally from pronotal lobe; lateral surface of propodeum with scatered, long, erect, yellow bristles emerging amid dense, appressed, white, plumose setae. Legs with abundant fuscous, dark fulvous, or fulvous bristles; corbicular bristles dark fulvous to black with pale yellow to off white apical halves, profundal bristles fuscous to black, marginal bristles dark fulvous to fuscous, some with off white tips; metabasitarsus with dark fulvous to fuscous bristles, sometimes with off white tips, prolateral surface with fine, erect, simple, fuscous to black setae. Metasoma with numerous, prominent, suberect to subdecumbent, yellow bristles on terga III – V arising amid tomentum, intermixed with a few fuscous to dark fulvous bristles with yellow tips.

♀: Latet.

♂: Latet.

HOLOTYPE: ⚲, Ecuador, Morona-Santiago, Santiago , II-86 [February 1986], legit L. Coloma ( SEMC).

ETYMOLOGY: The specific epithet is taken from both the province in which the holotype was collected (i.e., Morona-Santiago), as well as the middle name of Jesus Santiago Moure (1912–2010), who established the genus Scaptotrigona .

Figures

Figures 57–58. Workers of Scaptotrigona Moure. 57. Lateral habitus of Scaptotrigona baldwini, new species. 58. Lateral habitus of S. santiago, new species.