Discothyrea athene

Discothyrea athene is known from various localities in East Africa including Rwanda, Uganda, Kenya, Tanzania, and Mozambique, where it occurs in forest and woodland, usually but not always below 1000 m. It has been collected in riparian forest, swamp forest, and near streams throughout its range, suggesting a possible preference for mesic habitats. The species lives in leaf litter.

Identification
The following character combination distinguishes Discothyrea athene from the remainder of the complex:
 * standing pilosity absent from mesosoma and abdominal terga
 * propodeum denticulate
 * eyes present, relatively large (OI 5–9)
 * in dorsal view mesosoma relatively broad and robust (DMI 59–67, DMI2 92–100)
 * mesotibia without apicoventral spur
 * petiole attenuated dorsally (DPeI 300–500, LPeI 286–500)
 * sculpture distinct, declivitous face of propodeum foveolate
 * generally smaller species (WL 0.30–0.53)
 * color usually orange, variably infuscated

Distribution based on Regional Taxon Lists
Afrotropical Region: Kenya, Mozambique, Rwanda, Uganda, United Republic of Tanzania.

Nomenclature

 * . Discothyrea athene Hita Garcia & Lieberman, in Hita Garcia, Lieberman, et al. 2019: 31, figs. 4D, 6D-12D, 14D, 25, 26 (w.) UGANDA, KENYA, MOZAMBIQUE, RWANDA, TANZANIA.
 * Type-material: holotype worker, 4 paratype workers.
 * Type-locality: holotype Uganda: Kibale Nat. Park, Kanyawara Biological Station, 0.56437, 30.3605, 1510 m., FHG01060, 6-16.viii.2012, rainforest, leaf litter (F. Hita Garcia); paratypes with same data.
 * Type-depositories: BMNH (holotype); CASC, MHNG, SAMC, ZFMK (paratypes).
 * Distribution: Kenya, Mozambique, Rwanda, Tanzania, Uganda.

Description
Head fairly broad (CI 80–89) and round, posterior head margin gently convex; posterodorsal corners of head broadly rounded; in frontal view, sides of head convex and tapering somewhat anteriorly; eyes present, relatively large (OI 5–9) and round, comprising several ommatidia, placed about a third of the way between anterolateral corner of gena and posterior head margin; eyes visible in frontal view; frontal lamella broadly triangular in profile, apex rounded; lamella with translucent basal region, variably developed, from an indistinct patch to an elliptical and well-defined fenestra; medial clypeus convex, lateral clypeus curving gently between antennal sockets and anterolateral corners of head, bearing short, curved setae. Antenna with short scape (SI 48–53), scape strongly incrassate, slightly bent; pedicel subglobose, broader than long; true antennomere count nine; apparent antennomere count seven to nine; flagellomeres basad apical club highly compressed, taken together only about as long as apical club. Ventral head with postoccipital ridge weakly developed, without anteromedian carina; hypostoma medially rounded, arms somewhat narrowed, similar in width across their length; palpal formula not examined. Mandible edentate except for small, sharp prebasal denticle; basal angle broadly rounded; longitudinal carina on ectal face confluent with masticatory margin for most of its length, leaving small depressed triangular area anterad prebasal denticle.

Mesosoma gently convex, pronotum slightly lower than propodeum. In dorsal view mesosoma broad, robust (DMI 59–67; DMI2 92–100), somewhat narrowed posteriorly, pronotum wider than propodeum; pronotal humeri moderately rounded; posterior propodeal margin concave, distinctly concave between dentae; posterodorsal corners of propodeum angulate to dentate, teeth blunt but distinct; declivitous face of propodeum distinctly concave in profile and oblique posterior view; propodeal spiracle relatively large, subcircular, directed posterolaterally, often conspicuous due to shiny, unsculptured spiracular opening; propodeal lobes short, rounded.

Legs short to moderate in length (HFI 53–60) and slender; mesotibia without apicoventral spur, with small but distinct seta inserted in apical pit; mesobasitarsus short, about as long as tarsomeres II-IV taken together.

Petiolar node moderately to strongly attenuated dorsally, about 3.7 times higher than broad (LPeI 286–500). In profile, anterior face of node convex, apex broadly peaked, posterior face sloping posteroventrally. In dorsal view, petiole about 3–5 times wider than long (DPeI 300–500); sides divergent posteriorly, posterior margin slightly concave, anterior margin nearly straight. In anterior view, petiolar outline very wide, pentagonal, edges and apex slightly rounded but distinct; in oblique anterior view, anterior face flat; in ventral view approximately rectangular, sides diverging posteriorly; subpetiolar process large, lobate, apex rounded; petiolar spiracles reniform in ventral view.

Abdominal segment 3 roughly campaniform, tergite prolonged anteriorly pasted anterior sternal margin, tergite widest just anterad end of segment, sternite sloping to convex in profile; AS3 with scarce trace of medial carina; prora present as a very fine carina, shallowly concave in ventral view; AT4 about 0.85 the length of AT3 to slightly longer, usually approximately equal in length (ASI 85–103); AT4 almost perfectly hemidemispherical; AS4 with anterior lip short but fairly broad, covering more than the one-third of the width of AS3, anterior margin straight; successive abdominal segments short, telescopic, often concealed.

Sculpture on head, dorsal mesosoma, and petiole regularly punctate-reticulate or foveolate-reticulate; on ventral head surface and lateral mesosoma becoming foveolate to punctate; lateral mesosoma with interspaces of foveolate forming rugulae, especially on lower surfaces; declivitous face of propodeum shallowly foveolate-reticulate to laterally rugulose; mandibles with fairly coarse piligerous punctae; frontal lamella and medial clypeus roughly granulate; AT3 shallowly punctulate-reticulate; AT4 with minute, dense piligerous punctulae, clearly shinier than AT3.

Setation mostly consisting of very fine, appressed white pubescence, similarly distributed on dorsal surfaces, dilute to absent on lateral surfaces of head and mesosoma; abdominal sternite 3 with longer, curved decumbent white setae; abdominal segments five through seven with longer, flexuous standing setae; appendages with only very fine, appressed white pubescence; ectal face of mandible with curved, appressed to decumbent setae; row of straight, stout setae on masticatory margin.

Color unicolorous luteous-orange to brown, usually brownish orange, upper surfaces often slightly infuscated

References based on Global Ant Biodiversity Informatics

 * Hita-Garcia F., Z. Lieberman, T. L. Audisio, C. Liu, and E. P. Economo. 2019. Revision of the highly specialized ant genus Discothyrea (Hymenoptera: Formicidae) in the Afrotropics with X-ray microtomography and 3D cybertaxonomy. Insect Systematics and Diversity 3(6): 5:1-84.