Scaptotrigona caduceus 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 : 35-36

Scaptotrigona caduceus Engel , new species

ZooBank: urn:lsid:zoobank.org:act:EF8500B6-79DB-49AF-8DFE-BAA722A896D5

( Fig. 50 )

DIAGNOSIS: This is a species easily confused with S. ederi , but occurring to the East of the Andes. A distinct genal tooth is present and among such species it is perhaps most similar to S. illescasi (vide infra) but differing in the wholly black mesepisternum, the black tegular bristles, and the bristles along the entire mesoscutal margin black.

DESCRIPTION: As described for S. ederi (vide supra), with the following modifications: ⚲: Total body length approximately 5.9–6.0 mm, forewing length (to base of humeral sclerite) 5.5–5.6 mm. Head wider than long, width 2.27–2.33 mm, length 1.88–1.97 mm; compound eye length 1.33–1.39 mm; upper interorbital distance 1.39–1.45 mm, lower interorbital distance 1.33–1.36 mm. Scape length 0.85–0.88 mm, about as long as torulocellar distance, torulocellar distance 0.85–0.88 mm. Clypeus approximately 1.7–1.9× as wide as long, length 0.55–0.61 mm, width 1.06–1.08 mm. Malar area approximately 1.2–1.4× flagellar diameter or 0.55–0.65× 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 sharp, lamellate tooth; upper margin with lamella extended ventrally one third into concavity.

Integument of labiomaxillary complex yellow orange; labrum orange; mandible reddish orange; clypeus largely yellow orange to orange with brown along apical margin except sometimes with brownish stain on disc, triangular brown stain mediobasally, brown at apicolateral corners, epistomal sulcus well delineated by dark brown to black; supraclypeal area orange with stain of brown at epistomal sulcus; malar space often dark brown; face below tangent of antennal toruli orange, orange extending upward along inner orbit as narrow strip until about one antennal torular diameter above upper tangent of antennal toruli, remainder of face dark brown to black; scape orange, sometimes with brown dorsally; pedicel and flagellum brown above, flagellum orange underneath; vertex dark brown to black; posterior of head dark brown to black; upper third of gena dark brown to black, remainder of gena orange; postgena orange to yellow orange. Mesosoma black except pronotum orange to brown, mesoscutellum dark fulvous to ferruginous; tegula orange and semi-translucent; legs largely yellow orange to orange except dark brown on prolateral surface of protibia, posterior surface and anterior and dorsal surfaces apically on mesofemur, prolateral surface of mesotibia, prolateral surface of mesobasitarsus, metafemur apically, prolateral surface of metatibia except extreme base of fundus, superior and inferior margins of retrolateral surface of metatibia, and prolateral surface of metabasitarsus. Wing membranes hyaline clear to lightly parchment colored; veins light brown. Metasoma generally dark brown to black except anterior-facing surface of tergum I orange brown to brown, dorsal-facing disc of tergum I posteriorly coppery orange, tergum II posteriorly coppery orange, with narrow yellow marginal zone; terga III – IV with narrow apical marginal zones of light brown to yellow, typically obscured by tomentum; sterna dark brown to brown.

Areas of short, white, plumose setae in S. ederi instead yellow. Vertex with numerous erect, simple, dark fulvous bristles, a few short black bristles laterally near upper orbit; pronotal dorsolateral margin near and anterior to pronotal lobe with yellow and black bristles; mesoscutum anterior and lateral borders with largely black bristles, laterally black bristles intermingled with fulvous bristles; tegula with suberect black and fulvous bristles anteriorly; mesoscutellum with abundant, elongate, erect fulvous bristles posteriorly; mesepisternum with scatered, subdecumbent fulvous bristles, longer ventrally, along rounded anterior border with preëpisternum a line of abundant, suberect to subdecumbent black to dark fulvous bristles extending ventrally from pronotal lobe; lateral surface of propodeum with scatered, long, erect, fulvous bristles emerging amid dense, appressed, yellow, plumose setae. Legs with abundant black bristles except yellow to fulvous on coxae, trochanters, femora except metafemur apically, and distitarsomeres; metabasitarsus with erect black bristles on prolateral surface and margins. Metasoma with numerous, prominent, suberect to subdecumbent, yellow to fulvous bristles on terga III – V arising amid tomentum, such bristles sparser on tergum II.

♀: Latet.

♂: Latet.

HOLOTYPE: ⚲, Colombia: Meta, San Martin , 11-XI-1975 [11 November 1975], Monccuta leg. ( SEMC).

PARATYPE: ⚲, Colombia: Meta, San Martin , 11-XI-1975 [11 November 1975], Monccuta leg. ( SEMC) .

ETYMOLOGY: The specific epithet is the Latin noun cādūceus , meaning, “herald’s staff” and specifically the famed staff of the Roman god Mercury (Ancient Greek Hermês / Ἑρμῆς), and from which the name of the neighboring Reserva El Caduceo is derived.

Figures

Figures 49–50. Workers of Scaptotrigona Moure. 49. Lateral habitus of Scaptotrigona macarenensis, new species. 50. Lateral habitus of S. caduceus, new species.