Trigona (Nostotrigona) juvenili, Ribeiro & Nogueira & Oliveira & Oliveira, 2023

Ribeiro, Cristiano Feitosa, Nogueira, David Silva, Oliveira, Favízia Freitas De & Oliveira, Marcio Luiz De, 2023, Review of Trigona (Nostotrigona) Engel, 2021 from Brazil with description of three new species (Hymenoptera: Apidae: Meliponini), Zootaxa 5306 (3), pp. 349-366 : 357-359

Trigona (Nostotrigona) juvenili sp. nov. Ribeiro

( Fig 4A–D ; 6G–I )

Trigona recursa: Camargo et al. 2013 : [partim, catalog, geographic distribution].

Diagnosis: Integument predominantly black. Clypeus with abundant silvery decumbent hair on the lower paraocular area, and sparse and slightly brown on the upper half of the face. Mandible brownish black with a reddish-brown band near the apical edge, with five blackened teeth. Clypeus with erect setae of length approximately 0.17 mm, about 1.2× the diameter of the scape. Scape reddish brown on the dorsal surface and light brown on the ventral surface, with long erect setae (0.10 mm), about 0.7× the scape diameter. Clypeus with short distance between the epistomal suture and inferior tangent of the antennal socket, approximately 0.3× the scape diameter. Malar area with a length of approximately 0.8× the diameter of the scape. Carina post-ocellar low and smooth. Vertex with setae of lengh approximately 0.27 mm, about 1.9× the diameter of the scape. Mesoscutum with setae approximately 0.26 mm, approximately 1.9× the scape diameter, scutellum with longer setae (0.38 mm), approximately 2.7× the scape diameter. Metatibia relatively narrow and shallow, approximately 3× longer than wide. Metabasitarsus with posterior margin distinctly widened on apical half, apex with sharp angulation. Wing membrane hyaline, slightly smoky in the fifth apical and marginal cell. Veins and pterostigma brown. Metasoma elongated, approximately 2× longer than wide. Total body length approximately 5.3 mm of length.

Description: Coloration: Integument predominantly black. Clypeus black. Labrum brown blackened. Mandible brownish-black with a reddish-brown band near the apical edge, teeth blackened. Scape reddish brown on the dorsal surface and light brown on the ventral surface. Pedicel reddish-brown. Radicle light brown. Flagellum brown. Pronotal lobe, mesoscutum, axilla, scutellum, propodeum and mesepisternum black. Legs reddish-brown. Tegula reddish-brown. Wing membranes hyaline, slightly smoky in the fifth apical and marginal cell. Veins and pterostigma brown. T1 reddish-brown, T2–T6 brown-blackened. Sterna reddish-brown.

Pubescence: Clypeus and supraclypeal area with erect, black and branched setae (0.17 mm), approximately 1.2× the diameter of the scape, mixed with branched hairs of about 0.08 mm, approximately 0.6× the diameter of the scape. Clypeus and paraocular area with decumbent silvery hairs, on the denser lower than on the upper face towards the vertex. Scape with erect, black, branched setae, approximately 0.10 mm, about 0.7× the scape diameter, evenly distributed. Frons upper with erect branched setae, black, about 0.14 mm, mixed with branched hairs of about 0.07 mm. Vertex with erect branched, black setae, approximately 0.27 mm. Mesoscutum covered by erect branched setae, black and relatively long (0.26 mm), evenly and sparsely distributed on the disc and abundant on the anterior edge and on the sides. Mesoscutellum with erect branched, black setae, approximately 0.38 mm. Metatibia with simple erect setae on the posterior margin of about 0.41 mm, mixed with branched setae of approximately 0.35 mm. Metasoma: T1 smooth and polished; T2 with very fine, decumbent, and short setae forming a narrow apical band; T3–T5 with black, erect, and sparse setae. Sides of apical fourth of T3-T6 with abundant setae, forming a wide band; Simple setae T3 (0.09 mm), T4 (0.13 mm), T5 (0.16 mm) and T6 (0.18 mm). Sterna with simple setae (0.22 mm: 0.29 mm: 0.28 mm: 0.20 mm: 0.20 mm = length of S1-S5, respectively).

Punctation: Integument smooth and polished at the spaces between the piliferous punctures.

Proportions: Compound eye length 2.4× its width; inner orbits of the compound eyes concave, slightly converging downwards; compound eye length shorter than the upper and maximum interorbital distance, longer than the lower interorbital distance (1.34 mm: 1.44 mm: 1.51 mm: 1.19 mm = compound eye length and interorbital distances upper, maximum and lower, respectively). Malar area with 0.11 mm, about 0.8× the diameter of the scape. Clypeus length less than half its width (0.47 mm: 1.12 mm = clypeus length and width, respectively); clypeus slightly convex in lateral view; supraclypeal area slightly more prominent than the clypeus, at the level of the face. Labrum simple. Mandible with five well-defined teeth. Interalveolar distance greater than the diameter of the antennal socket and much shorter than the alveolorbital distance (0.25 mm: 0.15 mm: 0.40 mm = interalveolar distance, antennal socket diameter and alveolorbital distance, respectively). Frons slightly depressed along the midline. Vertex slightly convex, with post-ocellar carina. Interocellar distance (0.12 mm) is much smaller than the ocellorbital distance (0.40 mm). Scape length 5.7× its width (0.80 mm: 0.14 mm). Pedicel width slightly less than the diameter of the second flagellomere (0.13 mm: 0.15 mm). Paraboloid scutellum slightly projecting backwards. Metatibia approximately 3× longer than wide (2.15 mm: 0.71 mm). Metabasitarsus approximately 1.6× longer than wide (0.81 mm: 0.51 mm) with slightly convex anterior margin, distinctly widened posterior margin in apical half, concave distal margin. Metasoma elongated.

Male: Unknown.

Etymology: The epithet is homage to Juvenil Ferreira Ribeiro (in memoriam), father of the first author.

Geographic distribution ( Fig. 8 ): Brazil (Acre and Rondônia).

Biological note: Life history unknown.

Type material: Holotype (worker). Label data: Brasil, Acre, Acrelândia, 10°04’S / 67°25’W / 02–04/XI/2001, Oliveira, Morato & Cunha leg. ( INPA).

Paratypes (73 workers): BRAZIL, Acre: Acrelândia, 10°04’S / 67°25’W / 02–04/XI/2001, Oliveira, Morato & Cunha leg., 58 ( INPA); Brasiléia, 16.xii.1994. F.J.A. Peralta, 4 ( INPA); Cruzeiro do Sul , Serra do Divisor , 25/xi–08/ xii/2019, I. Junqueira leg., 1 ( MPEG); RBr [ Rio Branco ]—UFAC/PZ. Data 29/08/1995 / A.H. Machado, E.M. Santos / 0140, 1 ( INPA); idem, except “Data 17/08/1995 / 1258 / T.R. SMIT ”, 1 ( RPSP); Rio Branco , 10.09.94, E.M. Santos, 1 ( RPSP); idem, except “11”, 1 ( INPA); 04—R. Branco–AC , BRAS.— 10/09/94 / A.H. Machado, 1 ( RPSP); idem, except “N241”, 1 ( INPA); idem, except “ Trigona recursa Smith, Det. Camargo , 199 [?]”, 1 ( INPA); Rio Branco. 09°58’S, 67°48’W / 06/IX/2001, Em Coussapoa, M.L. Oliveira leg., 2 ( MPEG) ; Rondônia: Campo Novo, 01/x/2002, Tânia Sanaiotti leg. Terra Firme Forest , 1 ( INPA) .

Comments: We assume here that the following characters are strong indications for separating this specie from others in the subgenus: a distinctly enlarged metabasitarsus on the apical half of the posterior margin, forming an acute angle, and relatively long length of the erect mesoscutum setae, about 1.9× the diameter of the scape.

Figures

FIGURE 4. Holotype of Trigona (Nostotrigona) juvenili sp. nov. A—Lateral habitus. B—Head, frontal view. C—Dorsal habitus. D—Metatibia and metabasitarsus. Scale bars: 1 mm.

FIGURE 6. Heads, scape and metatibia of the T. (Nostotrigona) species. A–C—Trigona (Nostotrigona) recursa Smith, 1863: A, head, frontal view (red arrow indicating the area between the epistomal suture and the inferior tangent of the antennal socket); B, scape; C, metatibia, lateral view; D–F—Trigona (Nostotrigona) daianeae sp. nov.: D, head, frontal view; E, scape; F, metatibia, lateral view; G–I—Trigona (Nostotrigona) juvenili sp. nov.: G, head, frontal view; H, scape; I, metatibia, lateral view; J–L—Trigona (Nostotrigona) permodica Almeida, 1992: J, head, frontal view; K, scape; L, metatibia, lateral view; M–O—Trigona (Nostotrigona) mandaloriana sp. nov.: M, head, frontal view; N, scape; O, metatibia, lateral view Scale bars: 0.5 mm.

FIGURE 8. Geographical distribution of Trigona (Nostotrigona). Scale bar: Kilometers.