Discothyrea damato

Discothyrea damato
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Proceratiinae
Tribe:	Proceratiini
Genus:	Discothyrea
Species group:	traegaordhi
Species:	D. damato
Binomial name
	Discothyrea damato; Hita-Garcia & Lieberman, 2019

Discothyrea damato is only known from Kenya, Rwanda, and Uganda where it occurs in forested areas at comparatively high elevations ranging from 1448 to 2200 m. Based on data from material sampled in Kenya and Uganda, D. damato lives in leaf litter.

Identification

Hita-Garcia and Lieberman (2019) - The following character combination distinguishes D. damato from the remainder of the complex:

masticatory margin of mandible edentate
frontal lamella with conspicuous, large, elliptical basal fenestra
anterolateral corner of gena not denticulate/dentate
eyes absent to tiny (OI 0–4)
in dorsal view mesosoma conspicuously thick, robust and stocky (DMI 59–66; DMI2 95–102)
in profile mesosoma not extremely convex and propodeum angulate to dentate
mesotibia without apicoventral spur
AT4 around 1.2 times longer than AT3 (ASI 117–128)
abdominal sternite 3 without any projecting lobe
anterior clypeal margin without conspicuous row of long, straight setae
dorsal surfaces of mesosoma, petiole, and gaster without standing pilosity

Discothyrea damato is in its overall gestalt characterized by the lack of specialized characters compared with most other members of the complex. It is most smilar to Discothyrea dryad, Discothyrea schulzei, and Discothyrea wakanda but lacks the standing pilosity found in these species. Additionally, the sculpture of D. damato is notably shallower relative compared with that of D. schulzei. Another species close to D. damato is Discothyrea athene, but both differ mostly in eye size (OI 0–4 vs. 5–9) and abdominal proportions (ASI 117–128 vs. 85–103).

Discothyrea damato displays some apparent intraspecific geographic variation in general body size. The material from Kenya and Uganda is significantly smaller (HW 0.37–0.39; WL 0.43–0.45) than the specimens from Rwanda (HW 0.43–0.45; WL 0.53–0.56). Nevertheless, apart from body size there is no other observable intraspecific variation.

Keys including this Species

Key to Afrotropical Discothyrea

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: 0.56437° to -2.49278°.


North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

Source: AntMaps

Distribution based on Regional Taxon Lists

Afrotropical Region: Democratic Republic of Congo, Kenya, Rwanda, Uganda (type locality).

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Biology

Castes

Discothyrea X-ray micro-CT scan 3D model of Discothyrea damato (worker) prepared by the Economo lab at OIST.

See on Sketchfab. See list of 3D images.

Discothyrea X-ray micro-CT scan 3D model of Discothyrea damato (worker) prepared by the Economo lab at OIST.

See on Sketchfab. See list of 3D images.

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

damato. Discothyrea damato Hita Garcia & Lieberman, in Hita Garcia, Lieberman, et al. 2019: 37, figs. 4F, 6F-12F, 14F, 29, 30 (w.) UGANDA, DEMOCRATIC REPUBLIC OF CONGO, KENYA, RWANDA.
- Type-material: holotype worker, 7 paratype workers.
- Type-locality: holotype Uganda: Western, Kabarole, Kibale Nat. Park, Kanyawara Biological Station, 0.56437, 30.36059, 1510 m., FHG01047, 6-16.viii.2012, rainforest, ex leaf litter (F. Hita Garcia); paratypes with same data or with codes FHG01020, FHG01024, FHG01039.
- Type-depositories: BMNH (holotype); CASC, HLMD, KSMA, MHNG, SAMC, ZFMK (paratypes).
- Distribution: Democratic Republic of Congo, Kenya, Rwanda, Uganda.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.

Description

Worker

(n = 15) EL 0.00–0.02; HL 0.45–0.53; HW 0.37–0.45; SL 0.24–0.29; PH 0.22–0.28; PW 0.28–0.33; DML 0.28–0.35; PrH 0.26–0.37; WL 0.43–0.56; HFL 0.25–0.32; PeL 0.06–0.09; PeW 0.17–0.21; PeH 0.17–0.23; LT3 0.25–0.35; LT4 0.31–0.43; OI 0–4; CI 79–85; SI 51–62; LMI 48–53; DMI 59–66; DMI2 95–102; ASI 117–128; HFI 54–61; DPeI 233–286; LPeI 243–314.

Head subrectangular, longer than broad (CI 79–85), posterior head margin flat to gently convex, with very weak impression medially; posterodorsal corners of head quite broadly rounded; in frontal view, sides of head weakly convex; eyes absent or extremely minute (OI 0–4), if present, tiny, pigmented spot situated about one-third of way between anterolateral corner of gena and posterior head margin, usually not visible in frontal view; frontal lamella rounded-triangular in profile; lamella with very conspicuous, large, elliptical basal fenestra; medial clypeus convex, lateral clypeus strongly curving between antennal sockets and anterolateral corners of head, sides of medial clypeus nearly parallel laterad antennal sockets, bearing very short curved setae. Antenna with scape of short to intermediate length (SI 51–62), scape clearly incrassate, gently bent; pedicel subcylindrical, broader than long; true antennomere count nine; apparent antennomere count eight to eleven; flagellomeres basad apical club highly compressed, taken together shorter than apical club. Ventral head with narrow, roughly V-shaped postoccipital ridge without anteromedian carina; median region of hypostoma triangular, arms narrowed and slightly spatulate apicolaterally; palpal formula not examined.

Mandible edentate except for small, sharp prebasal denticle; basal angle rounded; ectal face with longitudinal carina nearly confluent with masticatory margin for almost its entire length, leaving very narrow depressed masticatory strip including prebasal denticle.

Mesosoma in profile moderately high and relatively flat, pronotum significantly lower than propodeum, propodeum strongly angulate to dentate, posterolaterally conspicuously concave; in dorsal view mesosoma conspicuously thick, robust and stocky (DMI 59–66; DMI2 95–102), strongly narrowed posteriorly, pronotum much wider than propodeum; pronotal humeri rounded; posterior propodeal margin distinctly concave; propodeal spiracle directed posterolaterally; propodeal lobes well developed, lobate.

Legs short to moderately long (HFI 54–61) and slender; mesotibia without apicoventral spur or seta; mesobasitarsus relatively short, about as long as tarsomeres II–IV taken together.

Petiolar node moderately attenuated dorsally, about 2.4 to 3.1 times higher than long (LPeI 243–314); in profile, anterior face of node convex, apex peaked, posterior face sloping posteroventrally; in dorsal view, petiole subrectangular, sides diverging posteriorly, about 2.3 to 2.9 times as broad as long (DPeI 233–286); in anterior view, petiolar outline clearly pentagonal with somewhat rounded but well-defined angles, strongly peaked; in oblique anterior view, anterior face flat; in ventral view, roughly rectangular sides weakly diverging posteriorly; subpetiolar process comparatively long, lobate, apex rounded, and directed anteroventrally; petiolar spiracles large, elliptical to weakly reniform in ventral view.

Abdominal segment 3 campaniform, widest point just anterad end of segment; sternite more or less evenly convex in profile; AS3 with weak medial carina posteriorly broadening into a swollen lobe at around the sternite’s midline; AS3 without carinate prora, but still with anterior face distinctly depressed and anterior margin of ventral face arcuate in ventral view; AT4 hemidemispherical and around 1.2 to 1.3 times as long as AT3 (ASI 117–128); AS4 well-developed and broad, overlapping most of the width of AS3, anterior margin straight to weakly convex in ventral view; successive abdominal segments short, telescopic, often concealed, projecting strongly anteriorly.

Sculpture of mandible punctulate, moderately shiny; ventral head surface foveolate to punctulate; remainder of head, dorsal mesosoma, lateral petiole, and abdominal segment 3 conspicuously but shallowly foveolate-reticulate to weakly areolate, sculpture on lateral mesosoma less regular, reticulum becoming rugulose, area around propodeal spiracle smoother and shiny; declivitous face of propodeum predominantly finely reticulate-punctate; anterior and dorsal petiole relatively weakly sculptured, rugulose-reticulate to granulate; AT4 finely punctulate.

Setation generally very fine, dense, mostly appressed, very short pubescence; ectal face of mandible with moderately long, curved, subdecumbent to suberect setae; masticatory margin with row of short straight setae; abdominal segments 5 to 7 with moderately short standing setae.

Color usually uniformly orange brown to chestnut brown, with appendages of lighter color.

Type Material

See the beginning of this ("Nomenclature") section for detailed information about the specimen types. A cyber-type of the holotype is also available. This includes: Volumetric raw data (in DICOM format), 3D rotation video, still images of surface volume rendering, and 3D surface (in PLY format) of the physical holotype (The Natural History Museum: CASENT0247362) in addition to stacked digital color images illustrating the head in full-face view, plus profile and dorsal views of the body. The data are deposited at Dryad and can be freely accessed as virtual representation of the type. There is also a Sketchfab 3D surface model of the holotype. It is shown above, in the Caste section, and at Sketchfab (see the link in the Caste Section).

Etymology

The species name is a patronym dedicated to Anthony D’amato and his family in honor of his contributions to the conservation of life on earth and the discovery of biodiversity. The species epithet is to be treated as an appositive noun.

References

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.