Echinopla angustata, Zettel, Herbert & Laciny, Alice, 2015

Zettel, Herbert & Laciny, Alice, 2015, Contributions to the taxonomy of the ant genus Echinopla Smith, 1857 (Hymenoptera, Formicidae), Deutsche Entomologische Zeitschrift 62 (1), pp. 101-121 : 105-106

Taxon classification Animalia Hymenoptera Formicidae

Echinopla angustata sp. n. Figs 13-16

Type material.

Holotype (worker, NMM) from the Philippines, Negros Island, Negros Oriental Province, Valencia, Apolong, Casaroro Falls, slopes of Cuernos de Negros, 9-13.III.2005, leg. H. Zettel (420), in the National Museum of the Philippines, Manila; two paratypes (workers, ZCW) from the same locality, 3-4.III.2008, leg. H. Zettel (513).

Diagnosis

(worker). Predominantly black, small, slender species, TL = 4.6-4.8. Surface polyporous, pronotum with one pair of sharp tubercles, otherwise tubercles on mesosoma hardly developed. Head longer than wide (CI = 93-94). Mesosoma almost twice as long as pronotal width, with sharp, narrow mesometanotal suture. Pronotal width distinctly smaller than head width, if eyes excluded. Propodeum slightly shorter than promesonotum. Petiole with one pair of dorsal spines, without dentition below prominent lateral spines. Gaster tergite 1 anteriorly with relatively large pores and very narrow interspaces. Setae on dorsal surface, legs and scape relatively short. Short setae on tibia not reaching base of distally following setae.

Description.

Measurements of holotype worker: TL 4.6; HW1 1.10; HW2 0.93; HL 1.17; EL 0.23; SL 1.04; SW 0.13; HaL 0.11; PML 0.87; PMW 0.83; PpL 0.72; PpW 0.73; PH 0.50; PL 0.41; PW 0.83; GL 1.41; GW 1.15. Indices: CI 94; SI 95; MI 192.

Measurements of paratype workers: TL 4.8, 4.8; HW1 1.13, 1.16; HW2 0.98, 1.00; HL 1.22, 1.24; EL 0.25, 0.24; SL 1.11, 1.11; SW 0.14, 0.13; HaL 0.13, 0.10; PML 0.93, 0.93; PMW 0.87, 0.91; PpL 0.76, 0.76; PpW 0.76, 0.80; PH 0.55, 0.56; PL 0.42, 0.44; PW 0.87, 0.91; GL 1.54, 1.50; GW 1.24, 1.25. Indices: CI 93, 94; SI 98, 95; MI 195, 186.

Structures: Head longer than wide, subovate, with convex sides; dorsally and laterally polyporous, with closely set, relatively large pores, posterolaterally with a very few indistinct tubercles, matt; ventral surface smooth and shiny. Compound eye relatively small, strongly protruding, positioned slightly behind mid-length of head. Frons with prominent median carina; frontal lobes chiefly horizontally oriented, in dorsal aspect covering antennal fossae only in part, maximum distance of margins clearly behind mid-length, slightly greater than half of HW2. Clypeus with short, angularly elevated median carina, anterior margin straight. Mandibles striate, masticatory margin with five teeth. Antennal scape moderately long, almost straight, steadily widened from base to apex; antennomeres 8-10 approximately as wide as long.

Mesosoma slender, length roughly 1.9 times pronotum width; propodeum much shorter than promesonotum. Surface polyporous, with closely set, relatively large pores, dorsal margins with very few small tubercles. Pronotum rounded, but with distinct lateral teeth, distinctly narrower than head excluding eyes. Promesonotal suture absent. Mesometanotal suture sharp, narrow and deep. “Waist” in front of propodeum weakly developed. Legs moderately long, relatively slender.

Petiole stout, moderately wide, subtriangular in lateral, transverse in dorsal aspect; surface structure as on mesosoma; dorsal apex not sharply crested, bearing one pair of sharp, rather long teeth and occasionally a small medial denticle; below strongly developed lateral teeth without further dentition. Gaster tergite 1 considerably longer than wide, completely covering the following tergites; hind margin convex, serration blunt, in one paratype almost absent; surface polyporous, interspaces smooth and shiny; distances of pores everywhere clearly smaller than their relatively large diameters.

Pilosity: Entire trunk dorsally and laterally with dense, appressed white pilosity and moderately long white and grey standing setae; some standing setae on clypeus and on anterior declivity of gaster tergite 1 longer. White standing setae on scape about as long as the setae on head. Legs with fine appressed pilosity. Femora with only 0-2 standing setae on flexor side. Tibiae and first tarsomeres of middle and hind leg with oblique white setae; on tibiae their length greater than their distance.

Colour: Trunk black, without metallic shimmer, appearing grey by whitish pilosity. Antenna black or very dark brown, funiculus slightly paler towards apex. Mandible basally black, distally brown; other mouthparts yellowish. Legs chiefly black to dark brown; middle and hind coxa, all trochanters, and bases of femora yellowish to pale testaceous; tarsi towards apical tarsomeres reddish brown.

Comparative notes.

Echinopla angustata sp. n. differs from the previous three species by the much more slender body. The tubercles on the mesosomal sides are poorly developed except for one prominent pair on the pronotum. The petiole has no teeth below the lateral spines, and the pits on gaster tergite 1 are relatively coarse.

Etymology.

From the Latin adjective angustatus meaning narrow and referring to the slender body.