Heptacondylus, Smith

Smith, F., 1857, Catalogue of the hymenopterous insects collected at Sarawak, Borneo; Mount Ophir, Malacca; and at Singapore, by A. R. Wallace., Journal of the Proceedings of the Linnean Society of London, Zoology 2, pp. 42-88 : 71-72

Gen. Heptacondylus , Smith.

Head suborbiculate, wider than the thorax; eyes lateral and ovate; stemmata placed in a triangle on the vertex; antenna geniculated, filiform, the scape nearly as long as the flagellum, placed forwards on the head at the base of the clypeus; the flagellum 6-jointed, the joints clavate, except the apical one, which is cylindrical; the labial palpi 3-jointed; the maxillary palpi 3-jointed. Thorax ovate, gibbous; the scutellum very prominent; the metathorax armed with two acute spines (in the females), compressed and strangulated (in the workers). The superior wings with one marginal and one complete submarginal cell, the submarginal cell receiving the recurrent nervure; the superior angle of the discoidal cell touching the costal nervure. Abdomen ovate; the peduncle consisting of two nodes.

This is perhaps the most remarkable genus hitherto characterized amongst the Formicidae; it presents one of those anomalies which perplex the naturalist. In the aculeate division of the Hymenoptera, we have felt that there existed in every species certain undeviating and tangible characters, whereby the sex at least might always be discriminated; namely, an additional segment to the abdomen, whereby to distinguish the males, as well as an additional joint to the antennae; the number of joints in the male being thirteen, and twelve in the female. It is true that one or two exceptions have been recorded: thus, the male of Crabro vagus , amongst the fossorial group, has only twelve perceptible joints to the antennae; and amongst the Apidae, the males of the genus Coelioxys have apparently only six segments in the abdomen; in the latter ease, however, a seventh segment is concealed, or retracted, within the sixth segment; and in all probability, in the fossorial insect, a joint is concealed within the apex of the scape. In the present genus we find, however, so wide a departure from the normal condition, that it, stands almost alone, as an exception to the general rule. In the ' Transactions of the Entomological Society,' vol. ii. of the 2nd series, I established a genus ( Orectognathus ) on characters exhibited in a neuter Ant, the insect having only five joints in the antennae; but as a neuter cannot be fairly considered the perfect condition of a species, I have thought it possible that the discovery of the other sexes might prove that I had been premature in establishing a genus on the imperfect condition of the species. This cannot be urged in the present instance, as both the female and worker are described, and neither of them has more than six joints in the flagellum.