Prionopelta opaca Emery

Shattuck, S. O., 2008, Revision of the ant genus Prionopelta (Hymenoptera: Formicidae) in the Indo-Pacific region., Zootaxa 1846, pp. 21-34 : 29-30

Prionopelta opaca Emery

(Figs 6-7, 14-16, 22)

Prionopelta opaca Emery , 1897: 596 (larva described by Wheeler and Wheeler, 1964: 447).

Prionopelta mocsaryi Forel , 1907: 1 (junior synonym of P. opaca by Brown, in Wilson, 1958: 149).

Types. Prionopelta opaca Emery : Worker, queen and male syntypes from Papua New Guinea ( MHNG, MSNG, examined). Prionopelta mocsaryi Forel : Worker syntypes reported from Paraguay but probably in error for a SE Asian locality (see Brown, in Wilson, 1958: 149 for details) ( MHNG, not examined).

Diagnosis. Anterolateral corners of head, near mandibular insertions, rounded. Dorsal mesosomal sculpturing composed of foveae which are only slightly more dense on the pronotum than on the mesonotum and propodeum, and which are uniformly distributed across the width of the propodeum. Body small, head width less than 0.48mm but petiole relatively broad, PetW greater than 0.21mm.

Description. Anterolateral corners of head, near mandibular insertions, rounded and lacking a tooth. Dorsal pronotal sculpturing consisting of foveae which are only slightly more dense than on the mesonotum and propodeum. Foveae on dorsum of propodeum uniformly distributed across its width. Lateral mesosomal sculpturing consisting of small foveae on pronotum and anterior region of mesopleuron, ventral regions of mesopleuron and propodeum weakly striate, posterodorsal region of mesopleuron and majority of propodeum smooth. Fenestra present but weakly developed within subpetiolar process. Colour yellow-red to red-brown.

Measurements. (n=12) CI 76-80; HL 0.47-0.52; HW 0.37-0.41; ML 0.54-0.62; PetL 0.16-0.20; PetW 0.21-0.24; PI 110-136; SI 65-70; SL 0.24-0.27; T 1W 0.31-0.36.

Material examined (in ANIC unless otherwise noted). Palau: Peleliu I., E coast (Baker,R.H.). Micronesia: Pohnpei: Agric. Exp. Stn, Colonia (Clarke,J.F.G.; Gressitt,J.L.); Mt. Peipalap, Ponape Id. (Adams,P.A.); Mt. Tamatamansakir, Ponape (Gressitt,J.L.); Nanpil, Nett Dist., Ponape Is. (Dybas,H.S.); Ponape I., Colonia (Clarke,J.F.G.); SE Nanponmal (Gressitt,J.L.); Tolen Kiuh, Ponape Id. (Adams,P.A.); Kosrae: Kusaie I. (Gressitt,J.L.); Kusaie, Hill 1010 (Clarke,J.F.G.) ( ANIC, MCZC); Mt. Matante, Kusaie (Clarke,J.F.G.) ( ANIC, MCZC); Mt. Tafeayat, Kusaie (Clarke,J.F.G.) ( ANIC, MCZC); Mutunlik, Kusaie (Clarke,J.F.G.). Papua New Guinea: Central: Bisianumu, nr. Sogeri (Wilson,E.O.) ( ANIC, MCZC); Brown River (Woodward,T.E.); Brown River near Port Moresby (Balogh,J.) ( MCZC); Karema, Brown River (Wilson,E.O.) ( MCZC); East New Britain: Bainings, St. Pauls, Gazelle Peninsula (Gressitt,J.L.) ( MCZC); East Sepik: Kairiru (Okada,T.) ( MCZC); Yawasora nr. Wewak (Taylor,R.W.); Madang: Baitata, 30km NW Madang (Anderson,R.S.) ( CASC); Uho Village, 20km SW Madang (Anderson,R.S.) ( CASC); Morobe: 18km NW Wau (Anderson,R.S.) ( CASC); 22km NW Wau (Anderson,R.S.) ( CASC); 24km NW Wau (Anderson,R.S.) ( CASC); Bulolo (Lowery,B.B.); Bubia, 13km NW Lae (Wilson,E.O.) ( MCZC); Kilolo Creek, Wau (Balogh,J.) ( MCZC); Lae (collector unknown; Balogh,J.) ( ANIC, MCZC); lower Busu River, Huon Peninsula (Wilson,E.O.) ( MCZC); Nadzab (Wilson,E.O.) ( MCZC); Simbang, Huon Gulf (Biro) ( ANIC, MCZC); Timber Track, c.16km NW Lae (Taylor,R.W.); Wamuki, Mongi Watershed, Huon Peninsula (Wilson,E.O.) ( MCZC); Wau, north on Bulolo Road (Peck,S.) ( MCZC); New Britain: Keravat, Rabaul (Balogh,J.) ( MCZC); Northern: 8km S Kokoda (Taylor,R.W.); 8km S Kokoda (Taylor,R.W.); Dobuduru (Lowery,B.B.); nr. Kokoda (Taylor,R.W.); Popondetta (Room,P.M.); Sandaun: Bewani Road nr. Vanimo (Brown,W.L.) ( MCZC); nr. Vanimo (Taylor,R.W.); West New Britain: Kimbe District, Kavui Subdivision (Brown,W.L.) ( MCZC); Western Highlands: Baiyer River Sanctuary (Balogh,J.) ( MCZC). Solomon Islands: Bellona Is. (Greenslade^.); Kolombangara, near Kuzi (Roy.Soc.Exped.Brit.Mus.1966-1); Kolombangara, S Kusi (Greenslade,P.J.M.); Nila, Shortlands (Greenslade,P.); Guadalcanal: Koela, Sava Is. (Greenslade,P.); Kukum (Greenslade,P.); Mt. Austen(Greenslade,P.); nr. Malukuna Greenslade,P.); Visale (Greenslade,P.); New Georgia: Munda (Greenslade,P.); Mbarakoma, Vella Lavella Is. (Greenslade,P.); Nggela: Soso (Greenslade,P.); Rennell Is.: Hongaika (Greenslade,P.); Lughu Bay (as Kanggava Bay) (Greenslade,P.); Luka (Greenslade,P.); Magaegar (Greenslade,P.).

Comments. This species has so far only been found in rainforests with workers being collected from leaf litter on the forest floor. Nests occur in soil under objects and in rotten wood. P. opaca and robynmae have been collected from the same litter sample in PNG.