Diacamma generali

Identification
D i a g n o s i s : Large species (TL 12.7–15.7mm). Trunk with moderate or weak, greenish or bluish-green metallic shimmer. Mandibles brown, antennae and legs blackish. Erect setae abundant; fine pilosity well developed. Trunk strongly striate from genae to gaster tergite 1. Head (Fig. 54) moderately long, sides posteriorly of eye strongly convex. Posterior of head longitudinally striate until narrowly truncated hind margin; occipital margin ventrally terminating in very short, blunt teeth (Fig. 52). Eyes rather small. Clypeus (Fig. 54) entirely and usually very densely punctured, in some specimens with longitudinal rugae; apex forming a distinct, obtuse angle. Mandible with fine striation. Pronotum (Fig.53) with transverse-elliptical rugae. Striation on propodeum horizontal (Fig.52). Petiole (Figs.52, 53) very stout, its teeth relatively short and distant; subpetiolar process moderately concave between acute anterior and posterior corners, with oblique pilosity. Gaster tergite 1 (Figs. 52, 53) with coarse semi-circular striation.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Philippines.

D i s t r i b u t i o n : Philippines: northern and central Luzon, with records from the following provinces: Abra, Benguet, Zambales, Manila, Cavite, Batangas, Laguna.

Nomenclature

 *  generali. Diacamma generali Laciny, Pal & Zettel, 2015: 125, figs. 52-57 (w.) PHILIPPINES (Luzon I.).

Description
Structures: Head (Fig. 54) moderately elongate; sides strongly convex behind small eyes. Very coarse rugae present from genae to gaster tergite 1. Posterior of eyes, longitudinal rugae reaching narrow occipital margin. On ventral side of head occipital margin ending in a small, blunt tooth (Fig. 52). Clypeus (Fig. 54) densely punctured, almost matt except on apex; anterior margin medially forming a distinct obtuse angle. Mandibles usually with well-developed fine striation. Pronotum (Fig. 53) centrally with transverse rugae that are surrounded by slightly transverse-elliptical rugae. Rugae on mesopleura and propodeum sides almost horizontal (Fig.52). Posterior face of propodeum separated from sides by distinct carinae. Petiole (Figs.52, 53) stout, with rather short and distant spines; subpetiolar process moderately concave, both teeth acute, not strongly protruding; in lateral view, outline with rather short oblique pilosity; in ventral view narrow, carinae not very distinct. Gaster tergite 1 (Figs.52, 53) with thick, concentric, semi-circular or semi-elliptical rugae; along posterior margin finely punctured. Gaster tergite 2 (Figs. 52, 53) with fine, dense puncturation, weakly shiny. Pilosity (Fig. 52): Standing setae on trunk long and numerous, on mesosoma slightly shorter than on head and gaster. Short appressed pilosity abundant, but reduced on head posteriorly, pronotal disc, and sides of propodeum, densest on hind margin of pronotum, mesonotum, dorsal face of propodeum, and petiole. Standing setae on legs about as long as those on mesosoma, setae on scape distinctly shorter. Colour (Fig.52): Trunk with moderate or weak, greenish or bluish-green shimmer; gaster at apex and posterior margins of tergites pale brownish. Mandibles medium to dark brown, antennae and legs blackish, without metallic shimmer; tarsi dark brown. Notes: Diacamma generali sp.n. is a relatively common species in central Luzon and was frequently sampled by various collectors on Mount Makiling near the campus of the University of the Philippines, Los Baños, Laguna. Specimens usually have a greenish metallic shimmer that is reduced by a dense, short pilosity, but some specimens – chiefly from the more northern populations – tend to be almost black. A distinct blue or purple shimmer as in D. viridipurpureum was never observed. Diacamma generali sp.n. can be most easily distingushed from D. viridipurpureum and D. caeruleum sp.n. by the entirely punctured clypeus that forms an obtuse but distinct anterior angle. An additional character to distinguish it from D. viridipurpureum is its smaller eye size (EI 23–25 vs. 25–28, see Fig.56). Diacamma baguiense differs from D. generali sp.n. by a finer striation of gaster tergite 1; it is smaller (TL 9.8–11.6mm vs. 12.7–15.7mm) and never greenish. One of the D. generali paratypes in NHMW was used by Mayr (1862) for the description of the genus Diacamma, under the name D. rugosum.