Caenohalictus flammeus, Gonzalez-Vaquero, Rocio Ana & Roig-Alsina, Arturo, 2013

Gonzalez-Vaquero, Rocio Ana & Roig-Alsina, Arturo, 2013, Revision of the species of the bee genus Caenohalictus (Hymenoptera: Halictidae) occurring in Argentinean Patagonia, Zootaxa 3670 (4), pp. 493-515 : 505-507

Caenohalictus flammeus n. sp.

(Figs. 8, 20–22, 27–28, 34, 60)

Caenohalictus thauca: Rojas & Toro, 2000: 184 –185 (Not Schrottky 1909, misidentification).

Diagnosis. This species is easily distinguished by its shiny red mesoscutum, a bit faded or with green or coppery highlights in some males, and the compound eyes with brown hairs. Females have T3–T4 with a hairless marginal zone (as in Fig. 9), at most with a few hairs scattered on the sides, an unusual feature displayed only by this species and C. cyanopygus . The hind tibial spur is similar to that of C. opaciceps , but the teeth are rather parallel-sided instead of having a paddle-like shape ( Fig. 34 ). Male genital capsule (Figs. 20–22): see description below.

Description. Male (holotype). Length, 5.8 mm; forewing length, 4.7 mm (paratypes, length, 5.2–5.8 mm; forewing length, 4.4–4.7 mm).

Color: Head and mesosoma dark green with a metallic reddish tint on lower head area, mesoscutum, scutellum and metanotum. Following parts creamy-yellow: labrum, apical band of clypeus, anterior surface of flagellum and front of tibia I. Following parts dark brown to black: rest of antenna, malar area, mandible except reddish apex, tegula, legs and metasoma. Metasoma with a greenish tint on disk of terga. Wings light amber, with dark brown veins and pterostigma, base of costal vein light brown.

Pubescence: Whitish. Dark brown on compound eyes, lower area of face and frons. Compound eyes with hairs as long as MOD. Head with dense, short, plumose hairs on lower part of paraocular area; erect hairs on genal area as long as 1.7–2.5 times MOD; hairs on vertex as long as 2.3 times MOD. Thorax with plumose hairs on mesoscutum and scutellum (1.6–2.2 times MOD), longer on pleura and metanotum (up to 2.9 times MOD). Lateral side of propodeum with plumose hairs as long as 1.2–2.2 times MOD. Vestiture sparse on legs. Base of T1 with plumose hairs as long as 1–1.2 MOD. Terga with hairless marginal zones; disc of terga with very short erect simple hairs, as long as 0.2 times MOD, with slightly longer scattered plumose hairs, as long as 0.6 MOD; T2–T7 with some longer plumose hairs on lateral apical part, with their apices directed latero-posteriorly. S1 with plumose hairs up to 2.3 times MOD, shorter and very sparce on the following sterna.

Sculpture: Labrum impunctate. Clypeus with punctures separated by 1.5–2 PD, denser at sides, sparser apically. Lower paraocular area with punctation finer than that of clypeus, separated by 2–3 PD, sparser on supraclypeal area. Upper paraocular area with punctation even finer and sparser. Punctures on disc of mesoscutum, scutellum, pleura and propodeum separated by 6–7 PD; those on metanotum separated by 3–4 PD. Dorsal surface of metapostnotum and propodeum finely microareolate. Metasoma with fine, very sparse punctuation. Surface between punctures equally reticulate throughout the body, slightly finer on metasoma; marginal zones on metasoma substrigulate.

Structure: Head slightly broader than long, 1.04:1 (paratypes, 1.01–1.05:1). Proportion of lower to upper interocular distance 0.67:1 (paratypes, 0.66–0.71). Labrum twice broader than long, with a short apical median process; apical margin bearing a row of setae. Clypeus broader than long, 1.54:1 (paratypes, 1.36–1.52:1). Proportion of interantennal to antennocular distance, 1.7:1 (paratypes, 1.49–1.71:1). Proportion of posterior interocelar to ocelo-ocular distance, 1.03:1 (paratypes, 0.99–1.31:1). Proportion of length of scape, pedicel and first three flagellomeres 1.68:0.47:0.50:1.07:1 (paratypes, 1.53–1.78:0.40–0.61:0.43–0.61:1.01–1.22:1). Second flagellomere 1.74 times as long as its apical width (paratypes, 1.75–2.00). Pygidial plate apically rounded. S1 with a rounded apical median notch, the following sterna with their apical margin straight. S7 long and curved, with a median apical rounded process. S8 short, three times broader than long. Genital capsule (Figs. 20–22): igp reduced to a slender dorsal process with an acute apex, reaching the penis valve; penis valve with outer basal tooth; ogp not greatly expanded dorsally, with 3 setae, finely plumose apically; mgl half-moon shaped; va compressed, with its apical half tapering.

Female. Length, 5.6–5.9 mm; forewing length, 4.3–4.8 mm.

Color: dark green with a slightly golden tint on face, mesoscutum red. Black apical band of clypeus occupying more than half of its length, extending along the inner orbits up to level of antennal sockets. Sometimes disc of supraclypeal area dark purple. Following parts dark brown: labrum, mandible except reddish apex, scape, pedicel, posterior surface of flagellum, legs, sterna and marginal zone of terga. Anterior surface of flagellum light brown. Tegula translucid. Wings light amber with dark brown veins and pterostigma, base of costal vein light brown.

Pubescence: Whitish on paraocular area, gena, thorax except mesoscutum, and metasoma. Whitish to light brown on legs and T5. Dark brown on compound eyes, lower area of face, frons and mesoscutum. Compound eyes with hairs as long as MOD. Head with erect, plumose hairs; those on paraocular area and vertex as long as 1.7–2.9 times MOD; hairs on lower part of genal area 1.6–2.5 MOD. Thorax with plumose hairs on mesoscutum (0.8–1.4 times MOD), longer on pleura (2.1–2.8 times MOD) and metanotum (up to 2.1 times MOD). Lateral side of propodeum with very short, plumose hairs (0.2–0.3 times MOD) and intermixed longer hairs (up to 2.1 times MOD). Vestiture rather dense on legs. Terga with hairless marginal zones, at most a few hairs scattered on the sides of T3–T4; disc of terga with very short, erect hairs, laterally with some longer hairs with their apices directed latero-posteriorly. S2–S5 with long, simple hairs as well as rather long-barbed hairs, with their apices directed posteriorly.

Sculpture: Labrum with verrucose, median, basal elevation ( Fig. 60 ). Lower paraocular area with strong punctures, separated by 1–2 PD. Base of clypeus with punctures separated by 2 PD, slightly sparser on supraclypeal area; rest of face with punctation finer and sparser. Punctures on disc of mesoscutum, metanotum, pleura and propodeum separated by 6–7 PD. Scutellum with fine scattered punctures, and coarse punctures, even sparser. Dorsal surface of metapostnotum finely microareolate as propodeum. T2–T3 with punctures separated by 2–3PD, much sparser on T1, T4 and T5. Surface between punctures reticulate throughout the body, finer on clypeus, supraclypeal area and metasoma; marginal zones on metasoma substrigulate.

Structure: Head broader than long, 1.07–1.10:1. Proportion of lower to upper interocular distance 0.86–0.90:1. Clypeus broader than long, 1.77–1.91:1. Proportion of interantennal to antennocular distance, 0.65–0.71:1. Proportion of posterior interocelar to ocelo-ocular distance, 1.07–1.16:1. Inner hind tibial spur pectinate, with two to four straight teeth, the one which is nearer the apex bent down to the axis ( Fig. 34 ).

Etymology. This species is named flammeus, Latin word for fiery red, for the conspicuous, shiny red mesoscutum of the female.

Comments. Specimens of this species run, with some difficulties, to C. thauca in the key of Rojas and Toro (2000), a species name ascribed to Schrottky (1909) from Chubut. The original description of Oxystoglossa thauca mentions a green female with bluish reflections, terga with violaceous apical bands, and blue metasomal sterna. Schrottky describes a transverse carina bordering the posterior margin of the dorsal area of the metapostnotum, a feature absent in all the Chilean and Argentinean species of Caenohalictus seen by us. He also mentions a deep median sulcus on the mesoscutum and a total length of 7 mm. These features do not agree with the specimens studied by us, moreover, Schrottky does not mention a red mesoscutum, characteristic of C. flammeus . Moure (1944) and Rojas and Toro (2000) claimed to have studied the type of thauca , which nowadays seems to be lost ( Rasmussen et al. 2009) and we have not been able to locate it. The identity of Oxystoglossa thauca remains doubtful, until the type is located, or specimens agreeing with the original description are found.

Plants visited by C. flammeus n. sp.: Anacardiaceae : Lithraea caustica ; Asteraceae : Baccharis rhetinodes , Hypochaeris radicata , Matricaria inodora , Taraxacum officinale ; Fabaceae : Adesmia sp.; Iridaceae : Solenomelus sp.; Nothofagaceae : Nothofagus sp.

Distribution in Argentinean Patagonia. Humid to perhumid regions of Southwestern Neuquén, western Río Negro and northwestern Chubut. Also found in Chile: Valparaíso, Santiago Metropolitan Region, Bío Bío and La Araucanía.

Examined material. ARGENTINA : Holotype male: Nahuel Huapi: Valle del Challhuaco –41.242972 – 71.286694, 2–II–2011, R. González Vaquero, MACN –En 8254 ( MACN). Paratypes: Neuquén: 3M, Lago Moquehue, 28–I–2012, R. González Vaquero ( MACN). 3M, Villa Pehuenia, 27–I–2012, R. González Vaquero ( MACN). 1F, Lanín: Puerto Arturo Lago Lolog, 6–II–2012, pan trap, R. González Vaquero ( MACN). 1F, Lanín: Lago Curruhué Chico, 16–XII–2010, Compagnucci & González Vaquero ( MACN). 1M 1F, Camino Lagos Lolog- Curruhué, 7–II–2012, R. González Vaquero ( MACN). 4F, San Martín de los Andes Tr. Kura 1000m, 18/ 30–XI– 1985, M. & P. Gentili ( MACN). 1F, 8k N San Martín de los Andes 1000m, 16/ 22–XI–1997, Malaise trap, C. & M. Vardy ( MACN). 2F, 8k N San Martín de los Andes 1000m, 16/ 22–XI–1997, Malaise trap, C. & M. Vardy ( BMNH). 1F, 8k N San Martín de los Andes 900–1000m, 16/ 22–XI–1997, C. & M. Vardy ( BMNH). 1F, Nahuel Huapi: Cabecera E Lago Huechulafquen, 15–XII–1997, Roitman & Montaldo ( MACN). Río Negro: 3M, Nahuel Huapi: Valle del Challhuaco, 2–II–2011, R. González Vaquero ( MACN). 1M, Ñorquinco, 7–I–1965, A. Giai ( MACN). Chubut: 1F, INTA Trevelin, 3–XI–2006, A–I. Gravel ( PCYU). CHILE: Santiago Metropolitan Region: 1M, Cerro El Roble, 28–XI–2011, González Vaquero & Mondaca ( MACN). Valparaíso: 1F, Cerro Las Vizcachas, 1/ 12–XII–1982, L. Peña ( PCYU). Bío Bío: 4F, Las Trancas, Los Nirres, 3930ft, 11–XII–2006, L. Packer ( PCYU). 1M, Ñuble, Las Trancas, SE Recinto, 1200m, I–1984, L. Peña ( PCYU). La Araucanía: 1M, Lonquimay Lago Galletué , 2–II–1962 ( MLPA). 1M, Lonquimay Lago Galletué , 2–II–1962, Valencia ( MLPA). 2F, PN Nahuelbuta, Piedra del Aguila trail, 31–X–2001, Packer & Fraser ( PCYU). 1F, PN Nahuelbuta, 3860ft, 6/ 9–I– 2000, Webb & Yeates ( PCYU).

Figures

FIGURES 32 – 38. Hind tibial spur of the female. 32, C. opaciceps. 33, C. cyanopygus. 34, C. flammeus n. sp. 35, C. iodurus. 36, C. turquesa. 37, C. thamyris. 38, C. autumnalis. Scale 50 µm.

FIGURES 59 – 62. Labrum of the female. 59, C. cyanopygus. 60, C. flammeus n. sp. 61, C. turquesa. 62, C. thamyris. Scale 100 µm.