Andrena (Micrandrena) exigua Erichson, 1835

Dardón, María José, Torres, Félix & Ornosa, Concepción, 2014, The subgenus Andrena (Micrandrena) (Hymenoptera: Andrenidae) in the Iberian Peninsula, Zootaxa 3872 (5), pp. 467-497 : 477-479

Andrena (Micrandrena) exigua Erichson, 1835

Andrena exigua Erichson 1835:105 (Holotype examined)

Diagnosis. Individuals of this species are characterized by metasomal terga with evident PPs, and their BAPs have rough ornamentation over the entire surface. The clypeus, at least in females, has integument without ornamentation in the apical half, and although it is sometimes weak, it is always very shiny.

Redescription based on holotype. Female: Body length 6–7 mm. The body has dark brown integument, and the pubescence is usually whitish.

Head: The genal area has a shiny microsculpture without evident PPs, the pubescence is dense, whitish, and short, and the length is 0.5 that of the A1. The frons is striated, with rough ornamentation as in the supraclypeal and paraocular area, with the integument of the latter being smooth with PPs over the lower part. The area bounded by the apical margin of the compound eye, the lateral ocellus, and the top edge of the occiput have an evident, matte microsculpture. The facial fovea is large, extends beyond the lower edge of the antennal socket, and is covered with a velvety pubescence that is white or sometimes yellow. The width of the upper end is higher. The antennal basal part is darker than the apical region, and the A3 length is slightly less than A4 and A5 together. The clypeus is slightly arched, with microsculpture that is stronger in the basal area, which is normally smooth. In some specimens the microsculpture is weak, but it is always shiny, with scarce PPs which are greater in number in the distant apical part, E=3–4. The process of labrum is black and occupies, at its base, almost 0.3 of the lower margin of the clypeus. It is surrounded by slender yellow hair.

Mesosoma: The pronotum has a microsculpture with faint PPs. The scutum also has a microsculpture from the middle area, towards the posterior zone, although it is weaker and very shiny. The PPs are not deep, but they are evident, and are denser in the posterior region, E=1–3. The scutellum is almost entirely covered in a microsculpture that is very subtle and more lustrous than in the scutum; however, the PPs are similar to those in the scutum. The mesepisternum has a strong microsculpture, the PBHs are weakly bulky, E=2–4, and the hairs are brownish-white, reaching the length of A1 at the inferior region. The metanotum has a coarse microsculpture and the PPs are not evident. The basal area of propodeum has rough ornamentation, with no defined propodeal triangle. The propodeal corbicula is whitish-gray, dense, long, and plumose. The rest of the propodeum has a microsculpture, scarce hair, and no PPs. The wings are smoky and at rest are beyond the apex of the metasoma. The veins are yellow and the pterostigma yellowish-brown. The hind legs are dark; however, the basitarsus, mediotarsus, distitarsus, and tarsal claw are a hue paler. The tibia has a whitish-yellow pubescence and some darker hair in basal region, while the pubescence on the sides of the scutum, scutellum, and metanotum are large and brownish-gray.

Metasoma: The metasoma is regular, with shallow and smaller PPs than in the scutum. The discs of T1 have a weak microsculpture with evident marginal zones, and the PPs are obvious on the discs and marginal zones, E=2–3. T2 to T4 have a stronger microsculpture and more abundant PPs than T1, E=1–2. The marginal zones are broad, and are usually marked and occupy about 0.4 times the length of the terga. The metasomal bands are whitish and interrupted, and are present at up to 0.6 the width of each terga. T5 has a whitish-yellow pubescence, and the metasoma has reddish integument which is patent, especially towards the marginal zones. This is in contrast to the dark brown of the scutum or head.

Male: Body length 5–7 mm. The integument is brown with a reddish metasoma and legs. The pubescence is whitish-gray.

Head: The genal area has finely roughened ornamentation, and the pubescence is shorter than the length of A1, except at the upper edge of the compound eye where the hairs are longer. The vertex and frons are wrinkled, and the paraocular area is shiny with evident and oblique PPs. The area bounded by the apical margin of the compound eye, the lateral ocellus, and the top edge of the occiput have a strong and dull microsculpture that is parallel to the compound eye, which is weaker and brighter. The A1 to A3 are darker in color than the rest, and A3 and A4 are quadratic, with the same length, and are slightly shorter than A5. The clypeus could show a microsculpture (totally absent in the type of this species) and evident and dense PPs in the middle, with a smooth longitudinal line, E=0.5–2. It is covered with whitish-gray hairs that have a white hue in the distal border. The process of labrum is brown and surrounded by orange hairs, with a wider base than apex, and occupies (at its base) 0.3 of the lower margin of the clypeus. The head has a whitish-gray pubescence that is white in the genal area.

Mesosoma: The pronotum has a dull microsculpture. The scutum and scutellum have an opaque microsculpture, except in the middle where it appears weaker and shiny. In some specimens the whole scutellum is highly polished; however, in both, irregular PPs are present, E=0.5–3 to 5. The mesepisternum has an opaque microsculpture with abundant, bulky PPs, especially along the front, E=0.5–1, and a portion has a whitish-gray pubescence with hairs longer than the length of A1. The metanotum has a coarse and dull microsculpture. In the middle, the basal area of propodeum has thick and short folds at its base, while the apical portion is finer. The ornamentation on the sides is rough, and therefore, the propodeal triangle is defined. The wings are hyaline, and at rest do not reach the apex of the metasoma. The veins and stigma are of a yellow-white hue. The hind legs, including the basitarsus, mediotarsus, distitarsus, and tarsal claw, are orange in color, while the pubescence is whitish and also located inside of the basitarsus. The mesosoma has a pubescence of a conspicuous whitish-gray, and hairs are present on the sides of the scutellum and metanotum, however, they are more abundant than on the scutum.

Metasoma: The metasoma is lanceolate. T1 has a dull microsculpture and small, non-patent PPs, E=0.5–3. The marginal zones are weakly marked on the sides. T2 to T4 also have a dull microsculpture, that is weaker and shinier on the dorsolateral convexity, where the PPs are slightly evident and abundant, E=1–2. The marginal zones have obvious PPs, occupying, at most, 0.3 times the length of the terga. The metasomal bands are whitish, narrow, and widely interrupted in T2 and T3, while in T4 they are only hinted at. The male genitalia have a simple constitution, similar to that of Andrena minutula ( Kirby, 1802) .

Specimens examined. Holotype: Spain: Andalucía, 1 ♀, undated. No. 2489, 13/3.MBERLIN (as shown on the label). Other material: Iberian Peninsula: Spain: Alicante: 1 ♂, undated, Dusmet, J. leg., OLINZ. Almería: Las Negras, 50 Km E., 3 ♂, 27-IV-2003, Halada, J. leg., MJ. Dardón det., OLINZ; Sierra Alhamilla, Lucainena, 7 ♂, 25-IV-2003, Halada, J. leg., MJ. Dardón det., OLINZ. Castellón: 1 ♂, 18-IV-1921, Dusmet, J. leg., OLINZ. Ciudad Real: Pozuelo de Calatrava, 4 ♀, undated, La Fuente leg., MNCNM. Jaén: Sierra del Pozo, Puertollano, 1 ♀, 12-VI-2003, Kalfka, M. leg., MJ. Dardón det., OLINZ. Madrid: Aranjuez, 1 ♀, 01-IV-1926, Lindberg leg., OLINZ; Vicálvaro, 1 ♀, 02-IV-1926, Lindberg leg., OLINZ;Villaverde, 2 ♀, 26-III-1912 / 1 ♀, 25-III-1907 / 2 ♀, 10-IV-1907 / 1 ♀, 31-III-1908, Dusmet, J. leg., OLINZ; Villaverde, 2 ♀, undated, MNCNM. Málaga: Yunquera, 40 Km W, 1 ♂, 20-IV-2003, Halada, J. leg., MJ. Dardón det., OLINZ. Murcia: Sierra de Españula, 20 Km. SW, 2 ♂, 11-V-2003, Halada, J. leg., MJ. Dardón det., OLINZ. Valladolid: Zamadueñas, 1 ♀, 03-V-1979, Asensio, E. leg., USAL; 1 ♀, 03-V-1979, Asensio, E. leg., OLINZ. Zaragoza: Pina de Ebro, 10 Km E, 1 ♂, 18-V-1992, Osten, T. leg., OLINZ.