Caenohalictus autumnalis (Jörgensen)

(Figs. 38, 48–50, 57–58)

Halictomorpha autumnalis Jörgensen 1912:116 . Lectotype: male. Argentina, Mendoza, Chacras de Coria. Museo de La Plata, La Plata. Examined, present designation.

Caenohalictus autumnalis: Michener 1979: 188 .

Diagnosis. This species can be easily distinguished by the following combination of characters: body length 5.0– 5.5 mm, male very slender, head rounded, compound eyes with hairs shorter than 1/3 the diameter of the median ocellus. The metasoma is light brown, sometimes with greenish highlights at the base. The male has a creamyyellow apical band occupying more than half of clypeus, and a patch of appressed, very short plumose hairs on the lower paraocular area along the inner orbits (Fig. 57). The tarsi, foretibia, front side of the scape, pedicel and anterior surface of the flagellum of the male are yellow. Male genital capsule (Figs. 48–50): igp wide, entirely covered by short, flattened, truncated, specialized setae, plate not reaching the penis valve dorsally; penis valve with a smooth outer basal tooth; ogp without setae, extended dorsally with a rounded edge; mgl small, half-moon shaped; va compressed, elongate. Female with T3–T4 with hairy marginal zones and inner side of tibia I yellow.

Comments. The syntypes housed in the Museum of La Plata are a male with the left foreleg broken beyond femur, the antennae broken beyond first and second flagellomeres respectively, and only a basal stump left of the right forewing; a female with no metasoma is on the same pin. A male mesosoma and a female in good condition are on another pin. Both pins have the same labels: “ Argentina /Mendoza/ 30.V.1908 /P. Jörgensen” “ Halictomorpha / n. sp./ autumnalis ” (MLPA #2175). The syntypes match well with the original description, although the female legs and metasoma are mostly brown instead of green. The male specimen in the best condition on the first pin is designated here as the lectotype, and the remaining syntypes are designated here as the paralectotypes.

Caenohalictus autumnalis visits the plant species Geoffroea decorticans and Prosopis flexuosa (Fabaceae) . Jörgensen (1912) reported that this species also visits Baccharis salicifolia, Solidago chilensis, Taraxacum officinale (Asteraceae), Lobularia maritima (Brassicaceae) and Sphaeralcea bonariensis (Malvaceae) .

Distribution in Argentinean Patagonia. Arid regions of Río Negro. Also found in Catamarca, La Rioja, Mendoza, La Pampa and Buenos Aires ( Argentina).

Examined material. ARGENTINA: La Rioja: 2M, I–1925, M. Gómez (MACN). 1F, XI–1934, M. Gómez (MACN). 1M, Iliar, M. Gómez (MACN). Catamarca: 1M, Hualfin, 14–I–1981, A. Roig Alsina (MACN). Mendoza: 1F, Ciudad de Mendoza Zoológico, Roig & Debandi (IADIZA). 1F, Ñacuñán, 23–X–1994, G. Debandi (IADIZA). 1F, Ñacuñán, 7/ 9–XI–2001, G. Debandi (IADIZA). 1F, Ñacuñán, 2–X–2002, G. Debandi (IADIZA). 2F, Ñacuñán, 2–X–2002, G. Debandi (MACN). 1F, Ñacuñán, 14/ 16–VII–1997, S. Roig (IADIZA). Buenos Aires: 1M, San Blas, J.B. Daguerre (MACN). 2M, Algarrobo, 5–III–1958, A. Ogloblin (MLPA). La Pampa: 2M, Santa Rosa Laguna Don Tomás, 20–XII–2006, J.J. Martinez (MACN). 2M, Lihuel Calel, 13–II–2007, L. Compagnucci (MACN). 1F, Dique Las Carreras, 21/ 26–II–1993, S. Roig (IADIZA). Río Negro: 3M, Valcheta, II–1924, M. Gómez (MACN).