Strumigenys europs Fisher, 2000

Bolton, B., 2000, The ant tribe Dacetini. With a revision of the Strumigenys species of the Malgasy Region by Brian L. Fisher, and a revision of the Austral epopostrumiform genera by Steven O. Shattuck., Memoirs of the American Entomological Institute 65, pp. 1-1028 : 680-681

Strumigenys europs Fisher sp. n.

HOLOTYPE WORKER. TL 3.5, HL 0.85, HW 0.59, CI 69, ML 0.45, MI 53, SL 0.57, SI 96, PW 0.36, AL 0.95. Characters of scotti-complex. Mandibles in full-face view with outer margins very shallowly and evenly convex, the width approximately constant from the level of the proximal preapical tooth to near the base. Upper scrobe margin evenly and shallowly convex in full-face view, not bordered by a rim or flange, the eyes visible, the apices of the upper scrobe margins confluent with the sides of the occipital lobes through an even curve, without an angle separating the two. Maximum diameter of eye slightly greater than maximum width of scape, with 5 - 6 ommatidia in longest row. Scape narrow and subcylindrical, shallowly and gently curved; hairs on leading edge narrow and decumbent, sharply bent at basal third and flattened or spoon-shaped apically. Cephalic dorsum densely clothed with rows of appressed, narrow, spatulate or spoon-shaped groundpilosity, the upper scrobe margin fringed with hairs which are longer but similar in shape as those on the dorsum. Cephalic dorsum with 6 stout standing hairs arranged in a transverse row of 4 close to the occipital margin and a more anteriorly situated pair. Pronotal humeral hair flagellate; humeral angles rounded, lateral margin of posterior pronotum with a marginate projection. Mesonotum with a pairs of stout filiform hairs on the anterior margin. Propodeum with two pairs of short, fine, posteriorly curved hairs immediately anterior of propodeal spines. Dorsal alitrunk with sparse ground-pilosity that is similar in shape to pilosity on head. Dorsum of alitrunk in outline convex anteriorly and more or less flat posteriorly. Metanotal groove represented by a raised transverse ridge across the dorsum. Anterior mesonotum with a narrow flange above the mesothoracic spiracle; mesopleural hair organ set in a large circular notch. Propodeal tooth broadly triangular, spongiform, lamellate, pointed apically, subtended by a moderate lamella on declivity. Pronotal dorsum shiny, longitudinally rugulose with superficial punctures laterally. Mesonotal and propodeal dorsum densely reticulate-punctate. Sides of alitrunk smooth, reticulate-punctate peripherally and along vertical groove above mesopleural gland. Dorsum of petiole node smooth with faint punctate sculpture that appears almost effaced; postpetiole disc smooth and shiny. Spongiform appendages of waist segments greatly expanded, petiole with a well developed ventral strip. Basigastral costulae sharply defined, radiating on each side of a central clear area. Dorsal surface of petiole without standing hairs, postpetiole disc with a pair of filiform hairs on posterior margin only. Dorsal gaster with standing filiform hairs. Colour light brown.

PARATYPE WORKERS. TL 3.4 - 3.6, HL 0.79 - 0.85, HW 0.53 - 0.56, CI 65 - 67, ML 0.42 - 0.45, MI 52 - 55, SL 0.53 - 0.58, SI 100 - 108, PW 0.34 - 0.36, AL 0.88 - 0.94 (3 measured). One specimen with a less developed propodeal lamella, otherwise as holotype.

Holotype worker, Madagascar: 38 km. S Ambalavao, Res. Andringitra, 22 ° 12 ' S, 46 ° 58 ' E, 1680 m., 23. x. 1996, sifted litter (leaf mold, rotten wood), montane rainforest, # 820 (29) - 6 (B. L. Fisher) (MCZ). Paratypes. 3 workers with same data as holotype but coded (21) - 4, (35) - 4, (48) - 5 (BMNH, SAM).

NON-PARATYPIC MATERIAL EXAMINED. Madagascar: Massif de l'ltremo, 1630 m. (J. - M. Betsch); Res. Andringitra 1990 m. (S. RazafimantUmby); Massif d'Andringitra, Anjavidilava, 2060 m. (J. - M. Betsch).

Measurements of this material extend the range shown by the type-series: HL 0.78 - 0.86, HW 0.52 - 0.57, CI 62 - 68, ML 0.40 - 0.45, MI 51 - 55, SL 0.51 - 0.57 (8 measured). One of the three specimens from Itremo differed from the type-material by having a pair of standing hairs on the petiolar disc.

S. europs is most similar to finator and both can be distinguished from other species in the scorn-complex by having the mesonotum with one pair of stiff hairs and dorsum of petiole more or less smooth and shiny. S. europs and finator differ as follows.

S. europs

1 Postpetiole disc with a pair of hairs on posterior margin only.

2 Dorsum of petiole usually without hairs.

3 In full-face view hairs on upper scrobe margin decumbent and sharply bent at basal third.

4 Propodeal lamella well developed, widest section usually distinctly greater in width than eye.

5 Head longer and broader, HL 0.78 - 0.86, HW 0.52 - 0.59.

S. finator

1 Postpetiole disc with three pairs of filiform hairs.

2 Dorsum of petiole always with a pair of hairs.

3 In full-face view hairs on upper scrobe margin subdecumbent to suberect, curved through entire length.

4 Propodeal lamella represented by an inconspicuous, very narrow lamellate ridge.

5 Head shorter and narrower, HL 0.57 - 0.64, HW 0.44 - 0.50.