Pyramica oconitrilloae, John T. LONGINO, 2006

John T. LONGINO, 2006, New species and nomenclatural changes for the Costa Rican ant fauna (Hymenoptera: Formicidae), Myrmecologische Nachrichten 8, pp. 131-143 : 139

Pyramica oconitrilloae sp.n. ( Figs. 17, 18, 21)

Holotype worker: Costa Rica: Heredia Prov., La Selva Biological Station (10° 26' N, 84° 01' W), 50 m elevation, 28.X.1991, leg. J. Longino #3152, specimen code JTLC000007866 ( INBC).

Paratypes: 5 workers, same data as holotype, JTLC 00 0007867 ( MCZC), INBIOCRI001224829 ( LACM), JTLC 000007869 ( UCDC), INBIOCRI001224828 ( BMNH), JTL C000007868 ( USNM); dealate queen, same locality as holotype, 11.V.2000, leg. Project ALAS FOT/49/1-40, INBIO CRI002281849 ( JTLC); 1 worker, Costa Rica: Heredia Prov., 11 km ESE La Virgen (10° 21' N, 84° 03' W), 300 m elevation, 16.II.2004, leg. Project ALAS 03/B/BV/019, INB0003624227 ( JTLC); 1 worker, same data but 15.III. 2004, 03/B/BV/049, INB 0003624223 ( NMW); 1 worker, same data but 10.IV.2004, 03/WF/02/06, INB 0003621500 ( CASC); 1 worker, same data but 13.II.2004, 03/TN/03/ 003, INB 0003619372 ( INBC).

Diagnosis of worker: With the characters of the P. gundlachi group, sensu BOLTON (2000); inner margin of mandible evenly convex for nearly entire length; preapical mandibular dentition consisting of one small sharp tooth immediately proximal to apicodorsal tooth, followed by up to five minute denticles; eye with about 15 ommatidia; setae on leading edge of scape thicker apically but not broadly fan-shaped, first two setae (starting at base) strongly curving toward scape apex, next two strongly curving toward scape base, fifth curving toward scape apex; ground pilosity of clypeus, face, and promesonotum abundant, remiform, subdecumbent; dorsal face of propodeum and gastral dorsum lacking ground pilosity; katepisternum smooth and shiny, rest of mesosoma, head, petiole, and postpetiole punctate; metanotal groove not impressed, such that promesonotum and dorsal face of propodeum form single flat surface; gastral dorsum smooth and shiny with short, sparse basal costulae, plus variable extent of fine longitudinal striolation on basal fourth or less; pairs of stout clavate setae on sides of head at upper scrobe margin, upper face near vertex margin, pronotal humeri, mesonotum, and petiolar node; postpetiole and gaster with abundant stout clavate setae; color orange.

Measurements of holotype: ML 0.261, HL 0.506, HW 0.415, SL0.237, MeL 0.512.

Diagnosis of queen: Similar to worker in mandibular structure, surface sculpture, pilosity, and color; katepisternum smooth and shiny as in worker, rest of side of mesosoma punctate; gastral dorsum longitudinally striolate in basal fourth.

Measurements of queen: ML 0.273, HL 0.522, HW 0.436, SL0.253, MeL 0.603.

Etymology: Named for Nelci Oconitrillo, Project ALAS Parataxonomist from 1994 to 2001.

Range: Costa Rica.

Biology: At La Selva Biological Station, while night collecting in the arboretum, I found a nest under a bark flap at the base of a large Pithecellobium tree. I saw a worker carrying a collembolan prey item at the time of collection. Workers have been taken in Winkler and Berlese samples and a flight intercept trap at La Selva and at the 300 m site on the Barva transect in Braulio Carrillo National Park. A dealate queen was collected in a canopy fogging sample at La Selva.

Comments: Intensive collecting at La Selva Biological Station and the Barva Transect has revealed a complex of five closely similar but consistently separable species relat- ed to P. subedentata ( MAYR, 1887) . Pyramica subedentata occurs throughout the Neotropics, usually in lowland wet to somewhat seasonal sites, in both mature and second growth forests. It is often collected in samples of litter and rotten wood from the forest floor. Pyramica trieces ( BROWN, 1960) occurs on the Atlantic slope of Central America from Nicaragua to Panama, from sea level to 1100 m elevation. It occurs most abundantly in mature wet forest where, like P. subedentata , it inhabits leaf litter and rotten wood on the forest floor. The three new species described here – P. oconitrilloae , P. cascanteae , and P. paniaguae – occur as a graded series of elevational specialists, with P. oconitrilloae occurring at La Selva and the 300 m site on the Barva Transect, P. cascanteae occurring at the 300 m site and at a 600 m site in the nearby Arenal National Park, and P. paniaguae occurring at the 500 m, 1100 m, and 1500 m sites on the Barva Transect. These three all show a tendency to be arboreal, nesting under bark flaps or epiphytes and rarely occurring in samples of litter and rotten wood from the forest floor. A sixth species in this complex, P. connectens ( KEMPF, 1958) , occurs in Colombia and Ecuador.