Trigona ( Necrotrigona ) rondoniensis, Ribeiro & Nogueira & Oliveira & Oliveira, 2024

Ribeiro, Cristiano Feitosa, Nogueira, David Silva, Oliveira, Favízia Freitas De & Oliveira, Marcio Luiz De, 2024, Two new species of Trigona Jurine, 1807 with an illustrated key for the species occurring in Brazil (Hymenoptera: Apidae: Meliponini), Zootaxa 5458 (4), pp. 524-546 : 531-535

Trigona ( Necrotrigona) rondoniensis sp. nov. Ribeiro

( Fig. 5 A-D)

Trigona hypogea : Camargo et al. 2023: [ partim, catalog, geographic distribution].

Diagnosis. This species differs from other species of the subgenus mainly in the metabasitarsus with a protuberant posterior corner, projecting downwards, overcoming the line where it meets the next tarsus ( Fig. 5D ). In related species, metabasitarsus not shows protuberant posterior corner and does not project downwards ( Figs. 7A and 8A ). This species also differs from T. ( Ne.) crassipes by the relatively larger erect setae of the scape, about 0.9x the diameter of the scape (erect scape setae are relatively short, about 0.6x the scape diameter in T. ( Ne.) crassipes ). T. ( Ne.) rondoniensis sp. nov. it is also distinguished from T. ( Ne.) hypogea by the length of the erect setae of the mesoscutum relatively shorter, about 1.7x the diameter of the scape, in T. ( Ne.) hypogea these setae reach about 2.3x the diameter of the scape. Total body length approximately 6.0 mm.

Description

Coloration. Integument predominantly black; clypeus black; labrum reddish-brown; scape reddish brown on the dorsal surface and light brown on the ventral surface; pedicel reddish-brown; mandible brownish-black with a reddish-brown band near the apical edge, teeth blackened; radicle light brown; flagellum brown; pronotal lobe black; mesoscutum, axilla, and scutellum black; propodeum reddish-brown; mesepisternum black; legs reddish-brown; tegula reddish-brown; wing membrane hyaline; venation and pterostigma brown; TI-II brown–reddish, TIII-VI brown–blackened; SI-II reddish-brown, SIII-V brown-blackened.

Pubescence. Clypeus and supraclypeal area with black erect setae, approximately of same size ( 0.19 mm), approximately 1.2x of scape diameter, in clypeus setae simple and in supraclypeal area setae with two branches, interspersed with branched hairs of about 0.06 mm, approximately 0.4x of scape diameter; scape with erect, black, and branched setae, approximately 0.14 mm, approximately 0.9x the scape diameter, evenly distributed; upper frons with erect, black, and branched setae about 0.18 mm, interspersed with feathery hairs of about 0.06 mm; vertex with erect, black, and branched setae, approximately 0.26 mm; lower paraocular area with denser decumbent silvery hairs than clypeus and upper face towards of vertex; mesoscutum covered by erect branched black setae, with approximately 0.27 mm, evenly and sparsely distributed in disc and denser on anterior edge and close to pronotal lobes and sides; mesoscutellum with erect branched black setae, approximately 0.33 mm; metatibia with simple erect setae on posterior margin of about 0.43 mm, interspersed with branched setae of approximately 0.41 mm; TI smooth and polished; II-V with very fine, decumbent and short setae forming a narrow apical band; III-V with black erect, and sparse setae on apical fourth, denser and forming a wider band on sides (0.12: 0.16: 0.23 mm = length of TIV-VI, respectively); sterna with erect black setae (0.30: 0.24: 0.23: 0.20 mm = length of SIII-VI, respectively).

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

Proportions. Length of compound eyes 2.3x their width; shorter than upper and maximum interorbital distance, longer than lower interorbital distance ( 1.50 mm: 1.62 mm: 1.73 mm: 1.40 mm = compound eye length and interorbital distances upper, maximum, and lower, respectively); inner orbits concave, slightly converging downwards; malar area with 0.12 mm, about 0.7x of scape diameter; clypeus length less than half its width ( 0.57 mm: 1.33 mm = clypeus length and width, respectively); slightly flat in lateral view; supraclypeal area slightly more prominent than clypeus, at face level; labrum simple; mandibles with five well-defined teeth; interalveolar distance greater than diameter of antennal alveoli and much shorter than alveolorbital distance ( 0.29 mm: 0.18 mm: 0.43 mm = interalveolar distance, antennal alveoli diameter and alveolorbital distance, respectively); frons slightly depressed along the midline; vertex slightly convex, with smooth post-ocellar carina; interocelar distance ( 0.12 mm) much smaller than ocellorbital distance ( 0.46 mm); scape length 5.5x its width ( 0.88 mm: 0.16 mm); pedicel width slightly less than diameter of second flagellomere ( 0.14 mm: 0.17 mm); scutellum paraboloid slightly projecting backward; metatibia narrow, approximately 3.6x longer than wide ( 2.51 mm: 0.70 mm); metabasitarsus approximately 1.9x longer than wide (1.0 mm: 0.54 mm), with straight anterior margin and convex posterior margin on distal half, posterior corner protruding, projecting downwards, overcoming the line meeting the next tarsus; metasoma subtriangular.

Etymology. The specific epithet is a homage to the State of Rondônia, Brazil, where the holotype and other specimens were collected.

Geographic distribution ( Fig. 6 ). Brazil (Amazonas, Rondônia).

Biological Note. Life history unknown.

Type material. Holotype ( worker). Label data: BRA, Rondônia, Ouro Preto do Oeste, 10°43’07.80”S 62°13’33.90”O / 28.vii.2017, C.F. Ribeiro Leg. Eugenol, Copa, 13B / as Trigona hypogea Silvestri, 1902 , Det. Nogueira, 2018 / N°. 99, ( INPA) .

Paratypes ( 40 workers): BRAZIL, Amazonas: Manaus, PDBFF—Faz Esteio, 02°23’58”S – 59°52’20”W, 11– 15.i.2009, D. Storck–Tonon Leg. / Ponto 1 Nº. 86, 1 (MPEG); Benjamin Constant, 13.vi.2019, Malaise; Xavier, F.F. & Carmo, D. Leg., 1 (INPA); Rondônia: Itapuã do Oeste. FLONA do Jamari. Novo Mundo, NSA—2500, 09°15’16.15”S 062°54’12.49”W, IAG—Óleo de Cravo, 20.V.2013, M.A.P.A. Silveira / 2, nos. 357 e 352 (INPA); idem, except “331”, 1 (MPEG); idem, except “ 9°4’0”S 63°7’0”W 25.V.2013 / 382”, 1 (INPA); idem, except “NSB— 500, 9°5’0”S 63°7’30”W / 440”, 1 (INPA); idem, except “Potosi, NS1—4500, 09°14’16.15”S 62°54’12.49”W, IAG—Óleo de Cravo, 18.V.2013 / 56”, 1 (INPA); idem, except “Potosi, NS1—1500, 09°15’55.3”S 62°54’14.4”W / 8, nos. 19, 14, 12, 11, 20, 18, 13 e 55 (INPA); idem, except “10”, 1 (MPEG); idem, except “IAG—Óleo de Eucalipto / 70”, 1 (INPA); idem, except “Santa Maria, NSA—1500, 9°8’30”S 62°54’0”W, 29.V.2013 / 9, with consecutive numbers: 227, 226, 236, 225, 222, 224, 228, 223 e 229 (INPA); idem, except “230”, 1 (RPSP); idem, except “NSA—4500, 9°7’30”S 62°55’0”W, IAG—Cinamato de Metila, 29.V.2013 / 273”, 1 (INPA); idem, except “Novo Mundo, NSA—2500, 9°3’30”S 63°7’30”W, IAG—Óleo de Cravo, 20.V.2013 / 2, with consecutive numbers: 358 e 359 (RPSP); idem, except “353, 354, 329, 63 e 64, 5 (INPA); idem, except “Santa Maria, NSA—500, 9°9’30”S 62°54’0”W, 23.V.2013 / 207, 206 e 209, 3 (INPA); idem, except “NSA—2500, 9°9’0”S 62°54’30”W, IAG—Óleo de Cravo, 23.V.2013 / 135”, 1 (INPA).

Comparative Material Examined. Trigona ( Ne.) crassipes ( Fabricius, 1793) ( Fig. 7 ): Holotype (worker) was examined through of digital image. Label data: crassipes.

Trigona ( Ne.) hypogea ( Fig. 8 ): Paralectotype (worker) was examined through of digital image. Label data: “S. Terrestri, nido, Cochipó, 11.ix.1900 ”, Silvestri leg. / Trigona hypogea Silvestri, 1902 , Des. Camargo, 1984.

Trigona ( Ne.) necrophaga ( Fig 9 ): Paratype (worker) was examined through of digital image. Label data: Colon Prov. Panamá, Portobelo, 15 Km SW, “Santa Rita Ridge” / Road, Km 20. IV-85-Roubik, 850833 / Trigona necrophaga Camargo & Roubik, 1986 , PARATYPE.

Comments and Discussion. Trigona ( Ne.) necrophaga has a restricted distribution in Central America ( Costa Rica and Panama), being the only species of the subgenus that does not occur in Brazil. However, T. ( Ne.) crassipes and T. ( Ne.) hypogea have distributions restricted to South America, with a more frequency of occurrence in the Amazon region.

The holotype of Trigona ( Ne.) crassipes has only one label ( Fig. 7D ), according to Moure (1960) bearing “crassipes ” in Fabricius’ handwriting. In the original description, the habitat is “Americae meridionalis Infulis.”

Figures

FIGURE 5. Holotype of Trigona (Necrotrigona) rondoniensis sp. nov. A—Lateral habitus. B—Head, frontal view. C—Dorsal habitus. D—Metatibia and metabasitarsus. Scale bars: 1 mm.

FIGURE 6. Geographical distribution of Trigona (Necrotrigona). Scale bar: Kilometers.

FIGURE 7. Holotype of Trigona (Necrotrigona) crassipes (Fabricius, 1793). A—Lateral habitus. B—Dorsal habitus. C— Ventral habitus. D—Specimen label. Scale bars: 1 mm. Source: (Image copyright: NHMD—Natural History Museum of Denmark, Copenhagen, Denmark).

FIGURE 8. Paralectotype of Trigona (Necrotrigona) hypogea Silvestri, 1902. A—Lateral habitus. B—Head, frontal view. C—Dorsal habitus. D—Specimen labels. Scale bars: 1 mm. Source: (Image copyright: RPSP—Coleção Entomológica “Prof. J.M.F. Camargo” (RPSP), FFCLRP/USP”).

FIGURE 9. Paratype of Trigona (Necrotrigona) necrophaga Camargo & Roubik, 1991. A—Lateral habitus. B—Head, frontal view. C—Dorsal habitus. D—Specimen labels. Scale bars: 1 mm. Source: (Image copyright: RPSP—Coleção Entomológica “Prof. J.M.F. Camargo” (RPSP), FFCLRP/USP”).