Oxytrigona sauronica, Lepeco, 2024

Lepeco, Anderson, 2024, Contribution to the taxonomy of Oxytrigona Cockerell, 1917 (Apidae, Meliponini), Zootaxa 5506 (3), pp. 369-395 : 386-388

Oxytrigona sauronica sp. nov.

( Figure 6 )

Type material. Holotype, RPSP, female worker “ Colombia, Casanare,\ Tamara , 1.iv.2007,\ J. Carreno \(M190)” . Paratypes, RPSP, six female workers, same label ; AMNH, a female worker, same label; LABUN, a female worker, same label.

Comments. The species is known from a single locality in the Western slope of the Andean range in Colombia. However, workers exhibit a set of characteristics not found in other species of the genus, as noted below. Given its absence in the recent checklist of the Colombian stingless bees ( Flórez-Gómez et al. 2023), it is likely that O. sauronica sp. nov. is rare or has a very restricted distribution.

Diagnosis. The new species is mostly dark brown to black, with dark pubescence, except for the ventral half of the head, which is marble white to yellowish ( Figure 6A ). It can be distinguished from O. obscura by the shorter marginal cell, about 3.7 times longer than its maximum width (~4.7 times longer than the maximum width in O. obscura ); wings mostly hyaline with yellowish veins, brownish spots absent; and by the distal corner of the dorsal margin of the hind tibia with a dense tuft of densely branched brown setae ( Figure 6D ). It is the only species known with the mesoscutum with very few erect setae, mostly restricted to the anterior portion.

Description. Holotype female worker. Measurements. Approximate body length: 5.8 mm; maximum head width: 2.3 mm; length of forewing: 5 mm; maximum width of T2: 1.7 mm. Color. Ventral half of face marble white, becoming progressively dark towards vertex. Gena brown. Mandible predominantly light brown, with lighter spot proximally and black spot distally.Antennal scape dorsally black and ventrally yellow. Pedicel dark brown. Flagellum mostly dark brown, F1 yellow. Mesosoma predominantly dark brown. Mesoscutum entirely black. Mesepisternum lighter brown ventrally. Metanotum with yellowish spot medially. Legs predominantly dark brown, with lighter spots scattered. Tegula dark brown. Wing veins mostly brownish, becoming bright yellow distally. Pterostigma yellow. Forewing membrane light yellowish infumate on proximal half, becoming almost hyaline distally. Hind wing membrane hyaline. Metasoma predominantly dark brown, terga without distinct lighter areas posteriorly. T1 and S1 lighter brown. Pubescence. Predominantly dark brown on entire body, except for tiny white setae on face. Labrum with erect setae about 0.8 MOD long. Frons with tiny decumbent setae scattered, with few long erect setae on dorsal fourth of frons. Surface between mid and lateral ocelli with branched short setae. Erect setae of vertex up to 1.5 MOD in length. Antennal scape with erect dark setae restricted to distal end, up to 0.3 MOD in length. Pedicel with black erect setae with up to 0.2 MOD in length. F2 without distinctly long setae. Mesoscutum with erect setae with up to 1.5 MOD in length, becoming virtually absent posterior to mid-level of tegula; decumbent setae brownish, becoming branched on surface anterior to mid-level of tegula. Scutellum with long erect setae up to 4 MOD in length, shorter on anterior half. Mesepisternum with erect setae with up to 3 MOD in length; decumbent setae whitish, branched. Propodeum with whitish branched setae on lateral surfaces. Legs mostly with black setae, except for brownish setae scattered throughout. Distal corner of dorsal margin of hind tibia with dense tuft of densely branched brown setae. Wings with yellowish erect setae on veins and membrane. Metasoma with black erect setae among whitish shorter setae. Posterior region of T2 with dense erect setae with up to 0.3 MOD in length. Posterior region of T3 with dense erect setae with up to MOD in length; posterior margin lined with simple setae up to 0.2 MOD in length. Posterior region of T4 with dense erect setae with up to 2 MOD in length; posterior margin lined with simple setae up to 0.4 MOD in length. S4 and S5 with sparse black erect setae among dense shorter dark brown setae. T6 with dense erect setae up to 3 MOD. Integumental sculpturing. Head integument predominantly shiny, with scattered weak punctures, except for clypeus and paraocular area ventrad antennal socket with denser punctation. Mesosoma shiny, with relatively dense punctures, except for medial surface of propodeum, smooth and lacking punctures. Metasomal terga mostly loosely reticulate, becoming punctate on posterior surface. T2 smooth on anterior two-thirds. Structure. Head 1.2 times wider than its medial length; clypeus 2.3 times wider than its medial length; malar space 1.5 times longer than width of F3; distance between antennal sockets about 0.8 times socket diameter; minimum distance between lateral ocellus and eye about 1.2 times distance between lateral ocelli. Antennal scape 4.7 times longer than socket diameter. Scutellum 0.6 times longer than minimum distance between axillae. Fore femur 3.9 times longer than its maximum width, ventral margin not carinate; mid basitarsus 2.5 times longer than its maximum width; hind tibia 2.6 times longer than its maximum width, distal margin strongly incurved; hind basitarsus 0.8 times as wide as maximum hind tibial width, 1.3 times longer than its maximum width, posterior margin evenly curved, distal corner strongly projecting and forming an obtuse angle, distal margin straight. Marginal cell 3.7 times longer than its maximum width. Posterior margin of S6 widely rounded.

Male. Unknown.

Variation. The type series is composed of rather homogeneous specimens. Minimal differences can be noted in the length of the pubescence on the mesoscutum and scutellum.

Etymology. The name is a reference to Sauron, an evil figure from the fictional universe created by J. R. R. Tolkien (e.g., Tolkien 1977). The Latin suffix -ica indicates “pertaining to”. Fire bees are often related to “evil” figures due to their particular defensive behavior, as is an example Oxytrigona daemoniaca named by J. M. F. Camargo.

Distribution. Currently the species is only known from the type series, which was collected in the eastern slope of the Cordillera Oriental in Colombia (Tamara, Casanare).

Figures

FIGURE 6. Holotype worker of Oxytrigona sauronica sp. nov. (RPSP 09.0361) from Tamara (Casanare, Colombia).A) habitus, lateral view, scale bar: 2 mm; B) head and mesosoma, dorsal view, scale bar: 0.5 mm; C) head, frontal view, scale bar: 0.5 mm; D) hind leg, scale bar: 0.5 mm.