Dacatria

The single species of the genus is only known from a few collections. Rigato (1994) reported the collector (Dacatra) of the single type specimen stated the ant was found "in a nearly subtropical environment with bamboo trees growing on the southern slope of mountains, at rather low altitude, (500-1000 m)." Collections have also been made in evergreen forest.

Identification
Eguchi, Bui and Yamane (2011) - The worker of the single species in the genus has the following features.

Worker monomorphic; head in full-face view subrectangular, with a shallow central longitudinal furrow; preoccipital region forming a distinct carina which surrounds the pronotal neck; frontal lobe well developed and raised; frontal carina and antennal scrobe absent; median portion of clypeus raised, with nearly vertical anterior face; median clypeal seta absent; lateral portion of clypeus modified into a distinct ridge or wall in front of antennal insertion; posteromedian portion of clypeus narrowly inserted between frontal lobes; antenna 12-segmented with indistinct 3-segmented club; eye small, convex well laterad, located before midlength of side of head in full-face view; mandible triangular; masticatory margin of mandible with apical and two preapical teeth, followed by two small teeth (5 teeth in total); promesonotum domed, with a pair of rounded and low humeral tubercles; promesonotal suture absent dorsally; metanotal groove well defined, with a small prominence in front of groove; propodeal spine long; propodeal lobe developed, round; petiole with long peduncle and low node; postpetiole short and high; gastral shoulder absent; sting simple; standing hairs absent from dorsum of body (simple standing hairs present at apex of gaster and on mandible, and slightly clavate hairs on third segment of gaster).

The worker of Dacatria is easily distinguished from that of other myrmicine genera known from Vietnam by the morphology of lateral portion of clypeus and humeral tubercles of the promesonotum.

Distribution
Known from China, Republic of Korea and Vietnam.

Castes
This monotypic genus was described from a single worker of Dacatria templaris. A queen has been collected (USNM) but has not been described. Males are unknown.

Nomenclature

 *  DACATRIA [Myrmicinae: Stenammini]
 * Dacatria Rigato, 1994b: 155. Type-species: Dacatria templaris, by original designation.

Dacatria lacks some peculiar characters of tribes like Tetramoriini and Myrmicini. For instance Dacatria lacks an apical lamelliform appendage on the sting and the clypeus is not tetramoriine in shape; also it has no tibial spurs on second and third pairs of legs nor an anteroventral process of the petiole as in Myrmica and allied taxa. Besides these features Dacatria has a different body structure from members of those tribes.

The morphological similarity to the Attini is considerable, but the zoogeography suggest its exclusion from these. Major differences from the true fungus-growers are 12 segmented antennae. lack of squarniform, or other kind of dorsal body hairs: mandibles with shorter masticatory border.

Worker Diagnosis
Terrestrial (?) myrmicine ant with the following characters:

1. Palp formula 3. 2 (counted in situ).

2. Mandibles triangular. five-toothed. The teeth increase in size from the basalmost to the apical. First, second and third tooth (counted from the basal) are separated from one another by a diastema.

3. Clypeus raised in the middle; its lateral portions are shaped as blunt crests which surround the antennal insertions in front, delimiting two somewhat deep sockets. The crests are the continuations of the diverging edges of the flat median clypeal portion. Anteriorly the clypeus appears obliquely truncate, and it has a sharp and hardly prominent convex edge which is obtusely angled in the middle. Posteriorly the clypeus is narrow and is deeply inserted between the frontal lobes. Clypeal setae absent.

4. Frontal triangle poorly defined.

5. Frontal lobes surround the posterior part of the clypeus; they are strongly raised in comparison with it. Their borders are slightly converging in front.

6. Frontal carinae absent.

7. Head with a shallow central furrow which is deeper and wider in its centre; posteriorly it gets narrower joining the occiput without a break. The latter appears almost truncate in side view. The furrow is delimited by two faint longitudinal prominences which posteriorly diverge nearly at right angles.

8. Antennae 12-segmented, with a poorly defined club of three. The scape is robust, and approximately of the same thickness throughout its length; it is clearly bent and barely thinner near the base.

9. Eyes small and quite convex; they are placed a little in front of the midlength of the sides of the head. No more than five ommatidia in their longest row.

10. Occiput with a low backwards projecting nuchal border which surrounds the pronotal "neck".

11. Pronotum bears two rounded low tubercles in the middle.

12. Mesonotum with a smaller raised tubercle posteriorly.

13. Metapleural lobes present.

14. Metanotal groove well defined and deep in profile because of the presence of the mesonotal tubercle and of the raised anteriormost portion of the basal face of the propodeum.

15. Propodeum with two backward directed, sharp, diverging and a little apically upturned spines which are about as long as the distance between their tips.

16. Propodeal spiracles small and nearly circular. Their openings are directed backwards from two low and blunt prominences of the propodeal sides.

17. Petiole with an elongate peduncle and a nearly flat-domed low node. The spiracles are circular and very small, they are placed a little behind the midlength of the peduncle. Postpetiole higher and wider than the petiolar node. It abruptly falls on the basis of the gaster.

18. Tibial spurs absent from second and third pairs of legs.

19. Sting present and simple.

20. Hairs absent from the dorsum of the body. Simple hairs are present at the apex of the gaster and on the mandibles. Slightly clavate hairs on third segment of the gaster. Pubescence short, scattered; it is visible only on the appendices and on the gaster.

21. Integument thick, body appearance dull, gaster shining. Sculpture coarse and irregular, prevalently rugose or rugulose on head and alitrunk. Colour brick red throughout the body; gaster, legs, mandibles and funiculi have a yellowish tinge.