Phyracaces langi Emery 1901, new species
Creators: name: Wheeler, W. M.
Publisher: name: Zenodo
Year: 1922
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Formicidae
Phyracaces
Phyracaces langi

description: Phyracaces langi, new species
Worker (Fig. 4).- Length 4 to 5 mm.
Head subrectangular, a little longer than broad and a little broader behind than in front, its sides feebly and evenly convex, its posterior border broadly and rather deeply concave and somewhat truncated, the occipital border sharply marginate with the margination surrounding the blunt but projecting inferoposterior corners and continued forward along each side of the gula to the insertion of the mandible. Eyes moderately large, flat, in front of the middle of the head. Mandibles with slightly concave external and very finely and evenly denticulate apical borders. Carinas of cheeks very prominent, in the form of blunt, rectangular teeth. Frontal carinae erect, subparallel in front, more approximated but not truncated behind. Antennae rather robust; scapes three-fifths as long as the head, slender at the base but rather abruptly enlarged before the middle; joints 2 to 9 of funiculus broader than long, tenth joint larger, distinctly longer than broad, terminal joint tapering, not broader than the preceding and not longer than the two preceding joints together. Thorax subrectangular from above, about twice as long as broad, a little broader through the epinotum than more anteriorly, evenly convex above, without traces of dorsal sutures, truncated and sharply marginate anteriorly and posteriorly. The marginatum separating the bast: and declivity of the epinotum is enlarged to form a small blunt tooth on each side. The lateral borders of the dorsum are indistinctly marginate, especially in the epinotal region, but the sloping epinotal declivity is sharply marginate laterally. Petiole as broad as the epinotum, rectangular, about one and twotbirds as broad as long, with bluntly dentate posterior corners, marginate in front and on the sides, with truncated, slightly concave anterior, feebly convex dorsal and sloping posterior surface. Vcntrally in front it bears a large, triangular, compressed, subtransluccnt tooth. Postpetiole as broad as the petiole, as long as broad, very regularly rectangular, flattened above, with only its anterior border marginate. First gastric segment a little larger than the postpetiole, of a similar shape but broader than long, anteroventrally with a blunt tooth or tubercle. Pygidium subcireular, truncate, minutely and indistinctly spinulate on the sides, Legs rather slender, hind cox;e with a large rounded, translucent expansion at the tip on the inner side.
1 1918, Proc. American Ac. Arts Sc., LIII, pp. 215-205, 17 figs.
Shining; mandibles coarsely and sparsely punctate. Head with a large, smooth and very shining space on each side between the eye and frontal carina1; remaining surface with coarse, elongate punctures or foveola" and posteriorly with a few coarse ruga?. Thorax above and on the sides rather regularly longitudinally rugose, with indications of elongate foveola? on the humeri and truncated anterior surface; epinotal declivity more finely and regularly longitudinally striated. Sculpture of petiole above similar to that of the thoracic dorsum but with more numerous elongate foveolse in the interrugal spaces; on the postpetiole the foveola. arc larger and more abundant and the longitudinal ruga: much less distinct; first gastric segment, pygidium and posterior portions of remaining segments coarsely and evenly punctate, the basal portions of these segments more shining and very evenly striolate. Scapes finely, legs more coarsely and much more sparsely punctate.
Hairs grayish, bristly, suberect, moderately long, rather evenly distributed on the body, more abundant on the tip of the gaster, more appressed on the legs; tibia; and scapes with a few long, suberect hairs. Pubescence short, visible only on the punctate portions of the gaster.
Black; mandibles, antennae, legs, tip of gaster and sting piteous, coxae and middle portions of femora and tibia" darker.
Female.- Length 5 to 5.5 mm.
Very similar to the worker. Pronotum coarsely foveolate; mesonotum small, flat, somewhat pointed anteriorly, with its rugae converging in front. Postpetiole distinctly broader than the petiole and a little broader than long. Wings whitish hyaline, with very pale yellow veins and large, conspicuous, dark brown pterostigma.
Described from seven workers and eight females taken from a single colony at Lubila, "nesting in a mushroom-shaped termitarium against a tree in the forest" (Lang and Chapin).
Of the four described Ethiopian species of Phyracaces, langi is most closely related to P. foreli Santschi of the Gold Coast. The worker of this species, however, measures only 3.5 mm. and, judging from Santschii description, has a nearly straight occipital border, shorter antennal scapes, and different sculpture, especially of the head, petiole, and postpetiole. His figure of the petiole shows much longer posterior teeth than in langi. The specimen from Samkita, Gaboon, described by Santschi as the female of foreli measures 4 mm. and is so different from the worker in the shape of the petiole that I feel sure that it belongs to a distinct species, which may be designated as Phyracaces santschii, new species.
description: Published as part of Wheeler, W. M., 1922, The ants collected by the American Museum Congo Expedition., pp. 39-269 in Bulletin of the American Museum of Natural History 45 on pages 54-56