Melophorus kuklos Heterick, Castalanelli & Shattuck

Heterick, Brian E., Castalanelli, Mark & Shattuck, Steve O., 2017, Revision of the ant genus Melophorus (Hymenoptera, Formicidae), ZooKeys 700, pp. 1-420 : 98-100

Melophorus kuklos Heterick, Castalanelli & Shattuck sp. n.

Types.

Holotype minor worker from Simpson Gap 23.43S, 133.43E, Northern Territory, 6 October 1972, J. E. Feehan, [ANIC32-900095] (ANIC). Paratypes: major worker from slopes above Baroalba Springs 12.47S, 132.51E, Northern Territory, 13 June 1973, R.W. Taylor, Accession 73.608, [ANIC32-900094] (ANIC); dealate queen and 3 minor workers from c. 5 km S of Tor Rock 11.59'S, 133.05'E, 5 June 1973, Northern Territory, R.W. Taylor, outcrop area, Acc. 73.451 (BMNH); major and minor worker from slopes above Baroalba Springs 12.47S, 132.51E, Northern Territory, 17 November 1972, R.W. Taylor & J.E. Feehan, Euc. savanna, Acc. 72.1006, ANIC ANTS Vial 38.92 (MCZ).

Other material examined.

Northern Territory: Baroalba Spring (Taylor, R.W.), Western Australia: Augustus Island.

Diagnosis.

Melophorus kuklos is a member of the M. aeneovirens species-group (in full-face view, the anterior clypeal margin convex, apron-like and covering whole or part of the retracted mandible, except in M. nemophilus , the medial clypeal sector often produced so that it is protrusive when seen in profile; the psammophore frequently with coarse and well-separated ammochaetae, these always placed on or just above anterior margin; in profile, the propodeum elongate and oblique or broadly rounded), and the M. aeneovirens species-complex (in full-face view, psammophore ranged along or just above anterior margin of clypeus and following the curve of the margin; anterior margin of clypeus broadly medially produced, and often with central notch that may be deeply impressed, but is never acuminate at its midpoint; metatibia with maximum of two rows of preapical spines). In M. kuklos the tibiae possess stout, socketed, appressed to subdecumbent setae only, with fine, appressed pubescence lacking. In profile, the minor worker mesosoma is compact and has an arcuate outline. Melophorus kuklos most closely resembles M. aeneovirens , but in the former, in profile, the clypeus is straight or weakly and broadly convex, and produced over the mandible as a very pronounced ledge. In full-face view, the anteromedial margin of the major and minor worker clypeus is produced as a narrow flange that is distinctly notched or even forked at its midpoint. Also, in contrast to M. aeneovirens , the dorsum of the minor worker mesosoma is strongly arcuate and almost elliptical.

Minor worker description.

Head. Head approximately oval with straight sides; posterior margin of head extended posteriad as a convex, sloping surface with a slight medioccipital protuberance; frons shining with superficial shagreenation or microreticulation only; frons consisting exclusively or almost exclusively of well-spaced, appressed setae only (small, erect setae, if present, usually confined to ocular triangle or posterior margin of head). Eye moderate (eye length 0.20-0.49 length of side of head capsule); in full-face view, eyes set above midpoint of head capsule; in profile, eye set anteriad of midline of head capsule; eyes elliptical or slightly reniform. In full-face view, frontal carinae straight, divergent posteriad; frontal lobes curved inward in front of antennal insertion. Anteromedial clypeal margin narrowly convex and protruding, clypeal midpoint distinctly notched; clypeal psammophore set at or just above anterior clypeal margin; palp formula 6,4. Five mandibular teeth in minor worker; mandibles triangular, weakly incurved; third mandibular tooth distinctly shorter than apical tooth and teeth numbers two and four; masticatory margin of mandibles approximately vertical or weakly oblique. Mesosoma. Integument of pronotum, mesonotum and mesopleuron shining and mainly smooth, vestigial shagreenation most noticeable on humeri and mesopleuron; anterior mesosoma in profile broadly convex; erect pronotal setae absent; in profile, metanotal groove generally shallow (NT) but may be more deeply impressed (WA), broadly V or U-shaped; propodeum shining and shagreenate; propodeum uniformly flattened along an oblique trajectory; propodeal dorsum and declivity confluent; erect propodeal setae always absent; appressed propodeal setulae short, separated by more than own length and inconspicuous; propodeal spiracle situated on or beside declivitous face of propodeum, and shorter (length <0.50 × height of propodeum). Petiole. In profile, petiolar node squamiform; in full-face view, shape of petiolar node square with rounded angles; node shining and smooth with vestigial sculpture. Gaster. Gaster shining with superficial microreticulation; pilosity of first gastral tergite consisting of well-spaced short, inconspicuous, appressed setae only, erect setae always absent. General characters. Colour dark brown.

Major worker description.

Head. Head square; posterior margin of head planar or weakly concave; cuticle of frons matt or with weak sheen, microreticulate; frons consisting exclusively or almost exclusively of well-spaced, appressed setae only (small, erect setae, if present, usually confined to ocular triangle or posterior margin of head). Eye small (eye length less than 0.2 × length of head capsule); in full-face view, eyes set above midpoint of head capsule; in profile, eye set anteriad of midline of head capsule; eyes elliptical. In full-face view, frontal carinae straight, divergent posteriad; frontal lobes curved inward in front of antennal insertion. Anterior clypeal margin narrowly convex and protruding anteromedially, clypeal margin entire or weakly indented, or narrowly convex and protruding anteromedially, clypeal midpoint notched; clypeal psammophore set at or just above anterior clypeal margin; palp formula 6,4. Five mandibular teeth in major worker; mandibles triangular, weakly incurved; third mandibular tooth distinctly shorter than apical tooth, but equivalent in length to remaining teeth; masticatory margin of mandibles approximately aligned vertically or weakly oblique. Mesosoma. Integument of pronotum, mesonotum and mesopleuron with weak to moderate sheen, shagreenate on pronotum and dorsum of mesonotum, otherwise microreticulate; anterior mesosoma in profile broadly convex; erect pronotal setae short, (i.e., shorter than length of eye) and unmodified; in profile, metanotal groove shallow, broadly V- or U-shaped; propodeum shining and shagreenate; propodeum smoothly rounded or with indistinct angle; propodeal dorsum and declivity confluent; erect propodeal setae absent; propodeal spiracle situated on or beside declivitous face of propodeum, and shorter (length less than 0.50 × height of propodeum). Petiole. In profile, petiolar node squamiform; in full-face view, shape of petiolar node uniformly rounded; node shining and smooth throughout. Gaster. Gaster shining, shagreenate ('LP record’ appearance); pilosity of first gastral tergite consisting of well-spaced, erect and semi-erect setae interspersed with regularly spaced appressed setae. General characters. Colour russet.

Measurements.

Worker (n = 4): CI 89-106; EI 16-29; EL 0.18-0.25; HL 0.69-1.48; HW 0.61-1.57; ML 1.02-1.74; MTL 0.54-0.87; PpH 0.12-0.17; PpL 0.52-0.87; SI 72-141; SL 0.86-1.14.

Comments.

All but two of the known collections of this compact little member of the M. aeneovirens group have been taken in the NT, although the collection localities range from the far north (Baroalba Spring and Tor Rock in Arnhem Land) to Simpson Gap in the West MacDonnell Ranges, near Alice Springs. The two exceptions are an ant collected on Augustus Island, WA, at a malaise trap (WAM) and a collection from Yampi Island Station, WA (TERC; tentatively this species). Melophorus kuklos is most similar to M. aeneovirens , from which it is distinguished by its more arcuate mesosoma and its strongly produced clypeus, which is bifurcated anteromedially. No specimens were available for sequencing, but its morphology suggests a close relationship with M. aeneovirens . Although ecological data are limited it appears to be catholic in its requirements, samples having been taken from a rocky outcrop, eucalypt savannah and rainforest.

Etymology.

Greek kuklos ( ‘circle’, referring to the species’ outline); noun in the nominative singular standing in apposition to the generic name.