Protomyrmica, Dlussky & Radchenko, 2009

Dlussky, Gennady M. & Radchenko, Alexander G., 2009, Two new primitive ant genera from the late Eocene European ambers, Acta Palaeontologica Polonica 54 (3), pp. 435-441 : 436

Genus Protomyrmica nov.

Etymology: From Greek “ prôtos ”—primary, initial, and the ant genus Myrmica .

Type species: Protomyrmica atavia sp. nov., by monotypy.

Diagnosis.— Antennae 13−segmented, without apical club, inserted into the head well behind the posterior margin of the clypeus; scape short, length of funicular segments decreases from the second segment to the apex. Frontal triangle absent (at least not separated from the head surface by sutures). Clypeus relatively long, gradually convex across its width, not inserted posteriorly between frontal lobes, its anterior margin widely rounded, without medial notch. Scutum with Mayrian furrows, propodeum somewhat angulated, with very short blunt tubercles. Middle and hind tibiae with big, distinctly pectinate spur, pretarsal claws simple. Mandibles elongate−triangular, with distinct, quite long masticatory margin, which has six small sharp teeth and long apical tooth; length of mandibles, measured from the outer point of insertion with head to the tip of apical tooth, subequal to head width (that is distinctly longer than in males of modern Myrmica species, where length of mandibles is much shorter than the head width). Forewing with closed cells 1+2r, 3r, rm, and mcu. Vein section 1RS is vertical, merging with vein R at a right angle. Cross−vein 2r+rs distinctly declined in respect to vein RS. Cross−vein rs−m is far distal with respect to 2r+rs (vein section 4RS present). Cell rm is pentagonal, reaching distally the level of the pterostigmal apex. Vein section 2+3RS has short fenestra proximally, on flexion line. Cell mcu is pentagonal (the vein section 2M is present) and generally trapezoid, reaching distally the level of the pterostigmal base. Cross−vein cu−a merging with the vein section 1M+ Cu close to the cell mcu (vein section 2M+Cu is short, subequal to cross−vein cu−a). Cell cua is absent, vein sections 1 Cu and 2 Cu forming more or less straight line, section 2 Cu does not sharply angulate distally and does not confluent with vein A. Hind wing with vein sections 1M and 2M.

Remarks.—Despite the maxillary and labial palps in the investigated holotype specimen being invisible, based on the general shape of the mesosoma, presence of the Mayrian furrows, the well developed and pectinate spur on the hind tibiae, structure of the antennae and general character of the wing venation we place Protomyrmica into tribe Myrmicini . By the antennal structure, Protomyrmica resembles Manica , but clearly differs from all other genera of Myrmicini , whose males have funicular segments that gradually increase in their length from the second segment to apex. On the other hand, Protomyrmica well differs from all genera of this tribe by the antennal insertions being situated well behind the posterior clypeal margin, and especially by its wing venation (for details see Discussion below).