Simopone trita, Bolton & Fisher, 2012

Bolton, Barry & Fisher, Brian L., 2012, Taxonomy of the cerapachyine ant genera Simopone Forel, Vicinopone gen. n. and Tanipone gen. n. (Hymenoptera: Formicidae) 3283, Zootaxa 3283 (1), pp. 1-101 : 66-67

Simopone trita Bolton & Fisher sp. n.

( Figs 73–75 )

WORKER (holotype in parentheses). HL 1.56–1.94 (1.68), HW 1.14–1.46 (1.26), SL 0.54–0.68 (0.56), EL 0.44– 0.55 (0.50), PW 0.95–1.16 (1.02), AIIW 0.91–1.18 (0.98), AIIL 0.85–1.06 (0.90), AIIIW 1.09–1.38 (1.17), AIIIL 1.00–1.22 (1.04), WL 1.82–2.20 (2.00), MFL 1.12–1.46 (1.18), CI 73–79 (75), SI 44–48 (44), EL/HW 0.36–0.40 (0.39), EP 1.15–1.55 (1.48), AIIW/AIIL 1.07–1.18 (1.09), AIIIW/AIIIL 1.06–1.19 (1.12) (15 measured).

In full-face view anteriormost points of frontal lobes are slightly posterior to the level of the midpoint of the convex anterior clypeal margin. Eyes located behind the cephalic midlength (EP 1.15–1.55). Leading edge of scape with 3–5 projecting setae that are curved or inclined toward the scape apex. In full-face view sides of head in front of eyes often with one or two projecting short setae, but behind eyes only with minute pubescence that is appressed or very nearly so. In profile frontal carinae with relatively long setae and cephalic dorsum with 2–3 standing short setae above the eye, and usually also with a very few setae that are located more posteriorly. Cephalic dorsum between eyes densely punctate, the punctures adjacent or nearly so. Anterior and dorsal surfaces of pronotum separated by an angle or weak margination, but without a strongly defined carina. Propodeal dorsum meets declivity through a blunt angle, without a transverse carina. Promesonotal suture weakly impressed; metanotal groove vestigial to absent. Mesosoma in dorsal view very obviously narrowest across mesonotum, much broader across pronotum and propodeum (in holotype PW 1.02, maximum width across mesonotum 0.80, maximum width across propodeum 1.00). Dorsum of mesosoma densely finely punctate everywhere. Mesosoma with a single pair of short setae, close to the pronotal humeri (easily abraded away, missing from holotype); mesosoma otherwise without setae but entire dorsum with appressed pubescence. Dorsal (outer) surfaces of mesotibiae and metatibiae mostly without projecting setae but one or two usually present close to their apices. Dorsal surface of AII (petiole) meets anterior surface in a fine transverse carina. Posteriorly the dorsum of AII lacks a sharp carina but a weak, arched ridge is present above the foramen. In dorsal view the posterior corners of AII are extended into stout triangular teeth that project posterolaterally. Lateral surface of AII, below the dorsolateral margin and above the level of the spiracle, with a longitudinal ridge or carina that extends the length of the sclerite. In dorsal view AII and AIII distinctly broader than long; AIV also broader than long. Abdominal tergites from AII to AIV often without setae, but a few may be present along the extreme apical margins of AIII and AIV; all three segments with quite dense, greyish appressed pubescence. Setae distinct on sternites of AIII and AIV. Abdominal tergites AII to AIV sculptured only with small punctures. Full adult colour black, appendages blackish brown to black; clypeus usually dull reddish; sides of pronotum and sides of abdominal tergites AIII and AIV often with a dull reddish spot, but this is variably developed and may be inconspicuous or absent on any sclerite.

Holotype worker (top specimen of three on pin), Madagascar: Prov. Antsiranana, Forêt Anlabe, 30.0 km 72° ENE Daraina , 30 m, 13°05.0’S, 49°54.5’E, 27–29.xi.2003, BLF9486, CASENT0499410, ex dead twig, above ground, littoral forest (B.L. Fisher) ( CASC).

Paratypes. 2 workers on same pin, below holotype; 2 workers from same series as holotype but labelled only BLF9486, CASENT0499410-RES ; 3 workers with same data as holotype but CASENT0499411 ; 3 workers with same data but CASENT0499412 ( CASC) .

S. trita and dignita form a small complex of species that in Madagascar is morphologically intermediate between the silens and emeryi complexes. They combine the reduced pilosity of the latter with the stocky AIII and posteriorly shifted eyes of the former. The two species are easily differentiated by the characters noted in the key, but in addition the posterior margins of tergites AIII and AIV in trita have a few short setae at most, whereas in dignita these margins each have a fringe of distinct setae that are obviously curved towards the midline.

Non-paratypic material examined. Madagascar: Ranomafana Nat. Park (E. Rajeriarison); Nosy Komba (G.D. Alpert); Prov. Antsiranana, Rés. Spéc. Ankarana, SW Anivorano Nord (B.L. Fisher); Prov. Antsiranana, Forêt Orangea, SE Remena (B.L. Fisher); Prov. Antsiranana, Nosy Be, Rés. Lokobe, ESE Hellville (B.L. Fisher); Prov. Antsiranana, Forêt Ampondrabe, NNE Daraina (B.L. Fisher); Prov. Antsiranana, Forêt Anlabe, ENE Daraina (B.L. Fisher); Prov. Antsiranana, Montagne Français, SE Diego Suarez (B.L. Fisher) .

Figures

FIGURES 73–75. Lateral, full face and dorsal view of body. Simopone trita holotype worker CASENT0499410.