Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia
|
|
|
Image of petiole.
Range
Costa Rica to Panama. Costa Rica: Atlantic lowlands, central valley, Guanacaste lowlands.
Identification
When mandibles are in their usual resting position, with tips crossed, they project beyond anterior border of clypeus, leaving a distinct gap; clypeus reduced, leaving labrum largely exposed; hypostomal teeth strongly developed, in full-face view projecting conspicuously into gap between clypeus and mandibles; petiolar node subcuboidal, dorsal and posterior faces meeting at a rounded right angle; cephalic dorsum punctate, variably smooth and shiny posteromedially; eye convex and large, diameter spanning almost one third the length of the lateral cephalic margin, eye dorso-laterally situated on head; scape with suberect hairs; propleuron striate; dorsal face of propodeum punctate, posterior face transversely striate.
Worker metrics (n=4). HL (1.11-1.27); HW (0.99-1.09); ML (0.76-0.91); EL (0.25-0.30); SL (1.16-1.34); WL (1.80-2.15); PH (0.71-0.81) mm. CI (0.86-0.89); MI (0.77-0.85); OI (0.26-0.28); SI (1.17-1.24).
Natural History
Longino has collected this species in La Selva as well as a nest series from beach strand vegetation at the Casa Verde turtle research station in Tortuguero, in a rotten branch attached to a tree close to ground level. Isopod remains were found within the nest.
Comments
This species has been found from Costa Rica to Panama. The head sculpture in this morphospecies varies from densely punctate (specimens from Central and NW Costa Rica) to sparsely punctate, and almost smooth posterad, with punctae limited mostly between and anterad of the compound eyes (specimens from Panama and NE Costa Rica). Guanacaste specimens have more regular striae on the pleura and lateral propodeum than other specimens. A single La Selva specimen is the largest of all, with rougher sculpturing and a broader head anterad than other specimens. It was not taken into account for the above description and was labeled as Leptogenys cf. JTL-004. The only other arcuata group species possibly sympatric with L. JTL-004 is L. donisthorpae. Leptogenys donisthorpae has the most robust mandibles of the arcuata group, and the lateroventral node area is not smooth and flattened but has weak rugosities. The hypostomal teeth are not visible in full face view, and the scape has decumbent hairs. Leptogenys JTL-004 has suberect hairs on the scapes, large hypostomal teeth, and a more prominent median clypeal lobe than L. donisthorpae. The propleuron in L. JTL-004 is smooth and shining, in contrast with the striate propleuron of L. donisthorpae.
Leptogenys arcuata is mostly South American, but has been taken on Caribbean islands, indicating the possibility of tramp species capabilities. Leptogenys arcuata is smaller than L. JTL-004 with a mostly smooth cephalic dorsum, except for sparse piligerous punctulae; the propodeal dorsum in L. arcuata is mostly smooth, whilst in L. JTL-004 it has shallow but quite distinct punctures. Leptogenys arcuata lacks the presence of appressed pubescence on the cephalic dorsum as in L. JTL-004.
Page authors:
John E. Lattke piquihuye@gmail.com
John T. Longino longinoj@evergreen.edu
Date of this version: 3 March 2009.
Previous versions of this page: 28 May 1999.
Go back to top
