Xenochilicola mamigna Toro and Moldenke

Genaro, Julio A. & Packer, Laurence, 2005, A revision of the genus Xenochilicola (Hymenoptera: Apoidea, Colletidae), with the description of a new species, Zootaxa 1054, pp. 1-14 : 3-5

Xenochilicola mamigna Toro and Moldenke

(Figs. 1, 4, 10–12)

Xenochilicola mamigna Toro and Moldenke, 1979 . An. Mus. Hist. Nat. Valparaíso 12: 145. Female and male.

Diagnosis. This species is easily separated from the other two by its linear malar space, this gives the head a rounded shape in anterior view such that the greatest length is slightly less than the greatest width. It differs from X. diminuta in lacking yellow bands on the metasoma in the male and by the absence of extensive areas of yellow, orange or red on the metasoma in the female. It can be differentiated from X. haroldotoroi n. sp. by the malar space character noted above, denser punctation on the mesoscutum and the genitalic characters noted in the key.

Description. Male. Body length 2.40–2.60 mm, forewing length 2.00– 2.04 mm (Fig. 4).

FIGURES. 1–3. Xenochilicola male heads in frontal view: 1. X. mamigna; 2. X. diminuta; 3. X. haroldotoroi n. sp.

Colouration. Black, with yellow as follows: labrum, mandible (except apex brown), clypeus, anterior spot on malar area which is variable in size, scape (ventrally), spot on tegula and pronotal lobe, apical 1/4 of all femora, dorsal surface and apex of foretibia, apices of mid and hind tibiae, tarsi (except last tarsomeres of mid and hind legs, brown).

Following parts brown: antenna (except scape ventrally), wing veins, marginal zones of terga and apical margins of sterna.

Surface sculpture. Microsculpture imbricate throughout except: labrum, clypeus, supraclypeal area, frons and vertex shiny, lacking microsculpture. Labrum densely punctured (i<d); frons, upper paraocular area and vertex with sparse punctures (i=1–4d), clypeus with denser punctures towards apex (i<d); lower paraocular area with small, more evenly spaced punctures (i~d); supraclypeal area with dense small punctures (i<d), gena with punctures longitudinally effaced (i>d); mesoscutum densely punctate­reticulate (i<<d, on disk, i<d laterally); mesoscutellum irregularly punctate (i<d); propodeum with basal area reticulate, posterior surface reticulate lateroventrally, imbricate with sparse irregular punctures elsewhere; hypoepimeral area rugulose with sparse punctures (i> 2d); preepisternum and mesepisternum sparsely punctured (i>d); metepisternum reticulatepunctate. T1 irregularly punctate on disc (i=0.5–3d), punctures large and dense laterally (i<d), acarinarium impunctate; T2 with sparse punctures, i>d, those on T3–T6 and S2 small and very sparse, remaining sterna impunctate.

Pubescence. White. Dense and apressed on paraocular area, dorsal surface of pronotum and anterior margin of mesoscutum (<MOD); long sparse hairs on clypeus, frons and vertex (>1.5MOD); shorter and denser on gena and sides of T1 (<MOD); short and sparse on metasomal terga and legs (<MOD). Lateral brushes of long hairs on apical margin of S5 (~2MOD).

Structure. Head almost as long as broad (0.92–0.97 mm: 0.90–0.95 mm). Labrum transverse, width:length 3:1, lateral margin almost straight, apical margin convex; stipes and cardo very long (~ 5.5–6.0 MOD), stipes slightly longer; clypeus convex, projecting approximately 0.4 of its length below lower ocular tangent (Fig. 1), apical margin weakly concave, lacking median longitudinal sulcus; antennal flagellomere I slightly expanded apicoventrally, remaining flagellomeres unmodified, length and breadth increasing proportionally from flagellomere II to XI; eye wider than gena in lateral view (2.7:2.0). OOC: IOC (1:2), UOD:LOD (5:3). Malar space short LMA:MW (1:2). Basal area of propodeum as long as metanotum half as long as mesoscutellum, in dorsal view (1:1:2). S5 with posterior margin concave, lateral margins angulate and hirsute; S6 produced medially.

Terminalia . S7 with large disc bearing one pair of broad apical lobes, apodemal arms triangular ( Fig. 10 ). S8 broad, abruptly narrowed towards base, apical process slender, hairy at apex; lateral apodeme slender, expanded anterolaterally ( Fig. 11 ). Genital capsule as in Fig. 12 . Digitus of volsella does not extend posteriorly beyond cuspis.

Female. Body length 3.32–3.48 mm, forewing length 2.44–2.60 mm.

Colouration. Black, except yellow as follows: spot on margin of pronotal lobe and tegula, apices of femora, foretibia dorsally and apicoventrally, apical 1/4 of mid­ and hind tibia, tarsi; variable amounts of yellow on mandibles, labrum and ventral surface of scape and flagellum; following parts brown: dorsal surface of flagellum, spot on disc of pronotal lobe, wing veins, marginal zones of terga. Sterna variable, generally reddish­brown, apical impressed areas translucent.

Pubescence. Similar to male except: apressed pubescence on paraocular area sparser; without lateral brushes of long hairs on S5, sterna with long hairs forming scopa on S1–S3 (>2.5 MOD). Hind leg scopa not developed, with sparse hairs ~1 MOD.

Surface sculpture. Similar to that of male except: clypeus variably punctate­reticulate. Sterna with large, sparse punctures, each bearing a scopal hair.

Structure. As in male except as follows: clypeus projecting approximately 0.5–0.6 of its length below lower margin of eyes; basal width of mandible longer than length of malar area LMA:MW 8.5:13.0. OOC:IOC (11:21), UOD:LOD (55:41). Antennal flagellomere I not expanded.

Holotype: CHILE, Tarapacá, Mamiña, 30.i.1972, coll. H. Toro, male, in collection H. Toro (AMNH).

Other Material Examined: ( Fig. 13 ). In addition to the holotype, the type series included additional specimens from the type locality as well as: CHILE, Región II: Tarapacá (Mamiña) and Antofagasta (Chiu­Chiu). Additional records are as follows: Región I, Hwy 687– 50.5 km, 83.5 km ESE of Pozo Almonte, S20º 18' 21 W69º 03' 13, 3930 m, pans, 8–20, iv.2004, coll. L. Packer (50 females; 5 males); Hwy 687– 46.8 km, 79.8 km ESE of Pozo Almonte, pans, 8–21, iv.2004, coll. L. Packer (7 females; 4 males); 12 km N of Belen, S18º24' 62 W69º30' 83 3735 m, 15.iv.2004, coll. L. Packer (1 female); Hwy 1, 111 km marker, S of Putre, S18º16' 18 W69º34' 21 3530 m, 14.iv.2004, coll. L. Packer (2 females); Tambo, 4 km W of Zapahuira, 4.iv.2000, coll. L. Packer (3 females); Pukara de Copaquilla, SW of Zapahuira, iv.2004, coll. L. Packer, pans (3 females); W of Zapahuira, 83 km mkr Hwy 11, iv.2004, coll. L. Packer, pans (1 female); Región II, 30 km E of San Pedro de Atacama, 3200 m, 24.iii.2000, coll. L. Packer, pans (3 females) and Gautín, near San Pedro de Atacama, S22º 45 W06º804, 3255 m, pan traps, iv.2004, coll. L. Packer (3 females). This material is in the AMNH and Packer bee collection at York University, Canada, most of the paratype series remains at the Universidad Católica de Valparaíso, Chile.

Comments. The sculpture of the disc of the clypeus in females is variable; in some specimens the reticulation is stronger, others have sparser punctation (i=1–1.5d) sometimes even with an impunctate area medially. This species has the weakest microsculpture of the mesoscutum and mesoscutellum in the genus. This small bee seems to be most easily collected using pan traps (for pan trap methodology see Droege, 2005).

Figures

FIGURE 13. Distribution of Xenochilicola species. X. mamigna; X. diminuta; X. haroldotoroi n. sp.

FIGURES 10 – 12. Male of Xenochilicola mamigna: 10. S 7; 11. S 8; 12. genitalia. Dorsal views to left, ventral to right.