Cephalotes quadratus

Identification
A member of the fiebrigi clade differing from the two species of its sister subclade, Cephalotes guayaki and Cephalotes fiebrigi, in the worker and soldier by the absence of erect hairs on the head, mesosoma and pedicel. (de Andrade and Baroni Urbani 1999)

Key to Cephalotes Workers

Distribution
Argentina, Paraguay.

Distribution based on Regional Taxon Lists
Neotropical Region: Argentina.

Nomenclature

 *  quadratus. Cryptocerus quadratus Mayr, 1868b: 175 (s.) ARGENTINA. Emery, 1896h: 634 (w.q.). Combination in Paracryptocerus (Harnedia): Kempf, 1958a: 33; in Zacryptocerus: Brandão, 1991: 388; in Cephalotes: De Andrade & Baroni Urbani, 1999: 660. Senior synonym of convexus: Kempf, 1958a: 33.
 * convexus. Cryptocerus convexus Santschi, 1916e: 382, fig. (w.) ARGENTINA. Junior synonym of quadratus: Kempf, 1958a: 33.

Worker
de Andrade and Baroni Urbani (1999) - Head broader than long and strongly convex dorsally. Vertexal angles round and with an obtuse denticle medially. Vertexal margin narrowly concave. Frontal carinae concave in front of the eyes and sinuous over the eyes. Mandibles laterally carinate.

Mesosoma strongly convex in side view. Scapular angles visible in dorsal view. Pronotum with a narrow lateral lamella bearing three pairs of irregular teeth, the first pair larger and obtuse and the second and third ones round. Sides of mesonotum with a pair of small denticles. Promesonotal suture poorly impressed. Propodeal suture impressed. Propodeum with differentiate basal and declivous faces and with the sides narrowing backwards; sides of the basal face of the propodeum with two pairs of teeth, the first pair simply angulate and the second one larger and pointed; sides of the declivous face of the propodeum unarmed, or with one or two small pairs of denticles.

Petiole anteriorly truncate; its anterior border weakly concave medially. Petiolar dorsum with a transversal carina separating its anterior face from the posterior one. Petiolar spines well developed arising from the anterior face of the petiole, pointed and strongly curved backwards. Postpetiole slightly broader than the petiole; its lateral expansions broad, spiniform, developed and directed anteriorly, strongly curved and pointed backwards.

Gaster suboval, with a pair of broad, anterolateral lobes.

Mid and hind femora not angulate; mid and hind basitarsi flat and with subparallel sides.

Sculpture. Body slightly shining, minutely and superficially reticulate-punctate. Head, mesosoma, pedicel and outer face of the femora and tibiae superficially foveolate, the foveae more impressed close to the vertexal margin and on the pronotum, irregular on the lower pleurae, on the pedicel and on the outer face of the femora and tibiae, rare or absent on the frontal carinae, on the declivous face of the propodeum, on the propleurae and on the upper meso- and metapleurae. Propleurae with additional thin, longitudinal rugosities.

Pilosity. Body with four types of hairs: (1) appressed and generally originating from each fovea; similar hairs on some body parts without foveae; (2) subclavate and rare on the border of the frontal carinae and on the legs; (3) subtruncate and rare on the dorsum of the first gastral tergite, sparse on the corresponding sternite; similar hairs but longer on the posterior borders of the gastral segments; (4) long, pointed and rare on the posterior borders of the sternites.

Colour. Brown. Frontal carinae dark yellow-orange.

Measurements (in mm) and indices: TL 4.26-4.56; HL 1.00-1.08; HW 1.06-1.16; EL 0.30-0.36; PW 0.92-1.00; PeW 0.58-0.62; PpW 0.60-0.65; HBaL 0.36-0.39; HBaW 0.07-0.08; CI 106.0-107.4; PI 115.2-116.0; PPeI 158.6-161.3; PPpI 153.3-153.8; HBaI 19.4-20.5.

Soldier
Kempf (1958) - Total length about 6.4 mm (not accurately measured when type was available); maximum length of head 1.62 mm; of thorax 1.80 mm. Fuscous-brown to black; anterolateral portions of head disc and shoulders reddish-brown; antennae and legs rufo-testaeeous. First gastral tergite quadrimaculate, the spots being yellow, rather small, the posterior pair at some distance from the apical border. Integument slightly shining.

Head subquadrate but slightly longer than broad (67:65), surmounted by an incompletely marginate disc, i e. anteriorly, anterolaterally and posteriorly the disc is sharply marginate, forming a slightly raised crest, which is distinctly crenulate anterolaterally. Postero-laterally, above eyes and the occipital lobes, the border is obsolete and the upper face is continuous with the sides of the head. In profile, the head is strongly convex above. Transversely, the disc is concave in front, gently convex behind. Clypeal sutures vestigial. Eyes situated behind and slightly above the antennal scrobe. Penultimate funicular segment nearly twice as long as the preceding segment. Occipital angles subrectangular and slightly crested. Head disc, occiput and sides coarsely reticulate-rugose and foveolate, with suberect, slightly curved and spatulate hair arising from each pit.

Thorax longer than broad (74:59). Shoulders distinctly dentate. Promesonotum conspicuously convex, as seen in profile. Transverse pronotal carina distinct at the sides, obsolete in the middle. Lateral border of dorsal face of pronotum distinctly marginate in front of the transverse carina, immarginate and rounded behind. Promesonotal suture vestigial at the sides, absent in the middle. Lateral borders of mesonotum forming a rounded, projecting lobe on each side. Mesoepinotal suture impressed, rather deeply laterally, more superficially in the middle. Sides of basal face of epinotum immarginate, with a projecting tubercular swelling. The posterior corner with an obtuse, stout, tubercular tooth. Posterior border, between the teeth, gently emarginate, not forming a marginate edge between the basal face and the declivity, which forms about a right angle with the former. Sculpture of dorsum of thorax almost as on head disc, but the pits are sparser, and the hairs arising from them are decumbent, silvery. Sides of thorax with still more scattered foveolae and the intervening spaces reticulate-rugose, the intervals between the rugosities being finely punctate. Extensor face of tibiae rugulose. Femora fusiform, tibiae and tarsi subcylindrical.

Petiole, in dorsal view, with evenly curved anterior border, which continues laterally as the anterior border of the recurved spines. In the middle, the body of the petiole has a gently impressed longitudinal furrow, flanked on each side by a vestigial swelling. From spine to spine, across the body of the segment extends a bluntly edged, sinuate, transverse carina. Postpetiole slightly broader than petiole, its lateral spines in the form of a pigeon wing, pointing obliquely cephalad at base, strongly recurved caudad. Transverse, blunt carina present, forming a feeble tooth middorsally. Both peduncular segments irregularly rugose, with longer, appressed scalelike hair.

Gaster deeply excised anteriorly, between the projecting, more or less rounded, anterolateral lobes, the border of which is neither crested nor lamellate. Gaster elongate, almost twice as long as broad, its sides subparallel. First tergite finely and densely punctate, with long, appressed, scalelike hair at base, the rest being subglabrous. The apical end of the following tergites and the sternites bear short, sparse, suberect hairs.

de Andrade and Baroni Urbani (1999) - Measurements (in mm) and indices: TL 6.48; HL 1.48; HW 1.48; EL 0.34; PW 1.40; PeW 0.72; PpW 0.76; HBaL 0.39; HBaW 0.10; CI 100.0; PI 105.7; PPeI 194.4; PPpI 184.2; HBaI 25.6.

Type Material
de Andrade and Baroni Urbani (1999):

Soldier. Type locality: Estancia Salvador near San Luis (San Luis, Argentina). Type material: Holotype soldier labelled “Salvador, Strobel. 9., Collect. G. Mayr, quadratus, G. Mayr Type” in (Kempf, 1958 a: 34), examined.

Cryptocerus convexus. Worker. Type locality: Estacion Sosa (Entre Rios, Argentina). Type material: 3 syntype workers labeled “Argentine, Entre Rios, Estacion Sosa, Mac Donagh”, in ; 1 worker (probably syntype) labelled “Est. Sosa, Cryptocerus convexus”, in, all examined.