Chilicola (Heteroediscelis) Toro & Moldenke, 1979

Monckton, Spencer K., 2016, A revision of Chilicola (Heteroediscelis), a subgenus of xeromelissine bees (Hymenoptera, Colletidae) endemic to Chile: taxonomy, phylogeny, and biogeography, with descriptions of eight new species, ZooKeys 591, pp. 1-144 : 6-26

Taxon classification Animalia Hymenoptera Colletidae

Chilicola (Heteroediscelis) Toro & Moldenke, 1979

Chilicola (Heteroediscelis) Toro & Moldenke, 1979: 98, 112. Michener 1992: 89. Michener 1995: 335, 337 (partim, as Chilicola (Oediscelis) ). Michener 2002: 11. Michener 2007: 182, 184 (partim, as Chilicola (Oediscelis) ). Packer and Genaro 2007: 41, 50. Packer 2008: 72-74, 77, 96. Almeida et al. 2008: 80-81. Moure et al. 2012. Monckton 2014: 234. Packer 2014: 254, 262. Ascher and Pickering 2015.

Type species.

Chilicola mantagua Toro & Moldenke, 1979, by original designation.

Diagnosis.

Males are readily diagnosable by S1 with a robust, elongate, ventrally directed process, with truncate apex having a well-defined (sometimes oblique) apical surface (other Chilicola that have such a process have it either spatulate as in Chilicola rubriventris or narrowing to a pointed apex as in some species of Oediscelis ). In females, the combination of protibia pale at least in basal half of dorsal surface, stigmal perpendicular basal to or interstitial with first recurrent vein (extending into basal quarter of second submarginal cell in some), and thorax ≤ 1.5mm wide separates this subgenus from all but three. From these, Heteroediscelis females are distinguished as follows: (1) from Unicarinicola by at least T1-T2 with apicolateral patches of white hair (lacking on all terga in Unicarinicola); (2) from Pseudiscelis by the pronotum not elongate, with medial length of collar at most one-quarter of anterior width of collar (at least one-third in Pseudiscelis ); (3) from Prosopoides by the absence of distinct and depressed facial foveae, although these are sometimes represented by a poorly delimited, not-depressed shiny area of reduced puncture density. The more mesal longitudinal depressions of the paraocular area in Chilicola neffi and Chilicola packeri partially accommodate the scape and are not homologous with facial foveae (for example, species of the subgenus Hylaeosoma possess both).

Redescription.

Small bees, length 4.2-6.8mm.

Colouration: Both sexes black to black-brown, margin of pronotal lobe yellow, tegula translucent yellow, wing veins brown to translucent yellow basally, tarsal segments II–IV of all legs variable from dark with apices yellow to entirely yellow, metasomal terga and sterna (T1-T6 & S1-S6 in males, T1-T5 & S1-S5 in females) with translucent yellow or amber marginal zones, wider on recurved lateral portion of terga, widened medially on sterna. Male antenna with ventral surface yellow to yellow-brown, and following parts yellow: labrum and most of mandible, markings on clypeus and lower paraocular area, and on all legs at least on femoral apex and tibial base. Female labrum variable but usually black-brown, mandible variable at least partially dark, face entirely dark (rarely with a yellow-brown or yellow spot on lower paraocular area below anterior tentorial pit, and a single specimen with a brown median spot on clypeus just above upper margin of anterior tentorial pits), ventral surface of antenna yellow or yellow-brown, and yellow on legs at least on tibial base of fore- and midleg, and following parts invariable: yellow apical ring on profemur, broader on anterior surface; yellow apicodorsal rim on mesofemur; yellow-brown apicoventral rim on coxa and trochanter of all legs.

Pubescence: White hairs generally short (0.5OD) and sparse, not especially plumose. Longer and denser on lower paraocular area and lateral margin of mesosomal dorsum. Mesal and lateral margins of scape with single row of long hairs forming a fringe. Genal beard longer and denser in males. Margin of pronotal lobe with short dense tomentum. Mesepisternum with long posteriorly curved hairs. Metasoma with apicolateral patches of white tomentum on at least T1-T2, apical margins of all terga otherwise with short and sparse appressed hairs and very sparse tiny setae medially. Male S1 with a few long, erect hairs basad of process, and S2 with long erect hairs dense, becoming shorter posteriorly. Female with scopae on metafemur and metatibia, corbiculate scopa on S2.

Surface sculpture: Microsculpture imbricate, integument generally dull; punctures generally small and deep. Mesosomal dorsum except metapostnotum densely punctate (i=0.5-1d), metapostnotum usually coarsely rugose. Legs variably puncticulate. Malar space microsculpture completely smooth, shiny, and moderately densely punctate (i=1-2d) along anterior ocular margin, becoming puncticulate-aciculate along posterior ocular margin, with dense minute punctures extending to middle of mandibular base in longer-faced bees. Male lateral surface of pronotum moderately densely punctate posteriorly (i=1-2d) densely punctate anteriorly (i≤d); in females moderately densely punctate throughout. Male metasomal T2-T5 basal depressed area coarsely microsculptured and punctures obscure; in females not coarsely microsculptured. Male metasomal sterna shallowly and sparsely punctate (i≥2d) punctures deeper and denser apicolaterally (i=1-2d); in females sparsely and minutely punctate throughout.

Structure: Anterior tentorial pits elongate, comma-shaped. Inner orbits of compound eye slightly convergent below. Length of pronotal collar medially ~1OD. Pronotum not elongate, at most one-quarter as long as anterior width. Probasitarsus elongate, ≥2.66 as long as maximum depth (usually ≥3). Metatibial spurs not unusually strongly sclerotized or curved. Metabasitarsus elongate, at least three times longer than maximum depth (usually ≥3.5). Stigmal perpendicular at first recurrent vein or in basal quarter of second submarginal cell. Male metafemur strongly swollen, weakly concave ventrally. Male metatibia robust and highly modified: shape approximately triangular in anterior view, with a ventral convexity leading to a rounded summit ventrally; deep longitudinal concavity on posterior surface; posterior surface with two longitudinal carinae: a ventral carina along inside of posterior concavity, and a posterior carina along lateral edge of posterior concavity (see Fig. 6B & D); apical lamina extending mediad from base of spurs, variable in shape and size, in part forming apical rim to posterior concavity. Metapostnotum well-defined, slightly depressed medially, longer than metanotum. Male S1 with a robust, elongate, ventrally directed process, with truncate apex with a well-defined and sometimes oblique apical surface.

Distribution.

Known from Chile, as far north as San Pedro de Atacama (Region II) and south to Cuesta Las Raíces (Region IX). Distributed throughout the Central Chilean sub-region, and found also in the Puna province (South American transition zone) and Maule province (Subantarctic sub-region); 0-3210m a.s.l.

Ecology.

Habitats range from Araucaria araucana Juss. forest to extreme desert. Recorded late August to late June, most abundant September to December.

Keys to the species of Heteroediscelis

Note: High magnification is required for some identifications; an ocular micrometer capable of distinguishing differences of 0.01mm is recommended. In frontal view, the perimeter of the median ocellus and the apex of the clypeus must be in the same plane of focus.

Males

Females