Aphaenogaster picena

Identification
Boer (2013) - In the Adriatic region A. picena is the largest species. Workers: The shorter scape and head, especially the relation between CI and SI and the less rugulose sculpture on the mesosomal dorsum are characteristic. Gynes: Compared with the other Adriatic species Aphaenogaster balcanica and Aphaenogaster campana, A. picena has a smaller petiole in relation to the postpetiole and the petioles are wider in these species, just like A. semipolita. However the latter has shorter propodeal spines and a shinier gaster. Males: The CI corresponds with A. campana, but A. picena is distinctly different from this species by the propodeal shape.

Distribution based on Regional Taxon Lists
Palaearctic Region: Albania, Croatia, Italy, Slovenia.

Nomenclature

 *  picena. Aphaenogaster picena Baroni Urbani, 1971a: 32, figs. 1-9 (w.q.m.l.) ITALY. [Aphaenogaster picena Baroni Urbani, 1966: 69. Nomen nudum.] See also: Baroni Urbani, 1971c: 41.

Description
Boer (2013):

Worker
Lateral sides of mesosoma with some longitudinal rugulae, usually weak or complete absent. Dorsal side of mesosoma (weakly) scabriculous. Head with longitudinal rugulae on frons, on the rest of the head less distinct, with some cross-connections. Terminal side of propodeum, beneath the propodeal spines smooth. Petiolar nodes punctate. Dorsal side of postpetiole punctate, with longitudinal costulae. First gastral tergite with microstriae. Mesosoma matt, with glossy punctation. Dorsal side of gaster matt to matt satin, beneath the propodeal spines glossy. Lateral sides of petioles and petiolar node glossy. Dorsal side of postpetiole and first gastral tergite matt. Lateral sides of first gastral tergite and legs wax glossy. Antennal club 4-segmented. Petiole with rounded top.

Measurements (n = 37). CI 77–84 (81); CL 1.32–1.64 (1.51) mm; CW 1.01–1.36 (1.21) mm; PHI 29–33 (31); PI 65–88 (75); PPPI: 49–58 (53); PSI 120–173 (153); PSLWI 96–160 (123); PWI 20– 25 (22); RPH 117–153 (135); RPSI 17–64 (43); SI 126–146 (135); SI/CI 154–190 (169); SL 1.43–1.77 (1.64) mm; SPD 1–2 (1.5); SPL 1–5 (2.9).

Queen
Longitudinal rugulae on clypeus, head, mesoscutum, scutellum and anterior side of postpetiole. Transverse rugulae on pronotum, propodeum and posterior sides of the petioles. Punctation distinct on head, weak on mesosoma and petioles. Less than ten transverse microstriae near base of first gastral tergite. Mesosoma slightly glossy, petioles and gaster satin. Anterior side of petiole smooth. Antennal club 4-segmented. Scutellum rises distinctly above mesoscutum and bends almost entirely over metanotum.

Measurements (n = 2). CI 88–91; CL 1.53–1.60 mm; CW 1.39–1.41; PHI 41–42; PI 67–68; PPPI 75–80; PSI 185–200; PSLWI 98–102; PWI 30–32; RPH 126–139; RPSI 47–49; SI 107–110; SI/CI 118–125; SL 1.48–1.55 mm; SPD 1–2; SPL 1–2.

Male
Rugulae are absent from the entire body, except for transverse rugulae (not in all individuals) on dorsal side and longitudinal ones on lateral sides of the propodeum; partly rugulose on mesoscutum and scutellum. Head, mesonotum and petioles punctate. Dorsal side of gaster microreticulated, longitudinal microstriae on base. Head, mesoscutum and petioles matt. Dorsal side of gaster wax glossy. Mesosoma matt with more or less glossy pits. Antennal club 5-segmented. Scape and legs microreticulated, shiny. Pubescence on scape and hind tibia decumbent, their length shorter than diameter of scape/tibia. Scutellum slightly erect above mesoscutum, partly bent over metanotum. With or without frontal midline. One large apical tooth, two or three smaller teeth, four denticles on masticatory margin of the mandibles. A groove between the two knobs at the terminal side of the propodeum. A distinct transverse groove in middle of propodeal dorsum, the posterior part of the propodeum is raised.

Measurements (n = 11). CI 91–100 (94); CL 0.87–1.06 (92); CW 0.82–0.96 (87); EYI 42–46 (44); OCI 41–44 (43); SL/CL 49–54 (51); SL 0.45–0.52 (47).

Type Material
Paratypes: Italy, Sirolo (Marche), 31.viii.1964, 12 workers, 2 males and 16.ix.1964, 1 male (Baroni Urbani; MSNV).