Rhopalothrix megisthmica Longino & Boudinot

Longino, John T. & Boudinot, Brendon E., 2013, New species of Central American Rhopalothrix Mayr, 1870 (Hymenoptera, Formicidae), Zootaxa 3616 (4), pp. 301-324 : 313-314

Rhopalothrix megisthmica Longino & Boudinot , sp. nov.

( Figs 1 B, 2C, 3F, 9, 16)

Type material. Holotype, worker. Guatemala, Zacapa: 2 km SE La Union, 14.94460 −89.27726 ± 57 m, 1550 m, 12 May 2009, cloud forest, ex sifted leaf litter (LLAMA Wm-B- 03-1-05) [CAS, unique specimen identifier CASENT0612564]. Paratypes (workers): same data as holotype but 14.94665 -89.27593 ± 50 m (LLAMA#Wa-B- 03-1-04) [USNM, CASENT0614540]; 14.94677 -89.27585 ± 50 m (LLAMA#Wa-B- 03-1-07) [MCZC, CASENT0614546]; 14.94723 -89.27707 ± 50 m (LLAMA#Wa-B- 03-1-45) [UNAM, CASENT0612503]; 14.95372 -89.27618 ± 50 m, 1430 m (LLAMA#Wa-B- 03-2-31) [UVGC, CASENT0629572; ECOSCE, CASENT0629573]; 3.5 km SE La Union, 14.95 -89.27 (unknown error), 1500 m, 4 Jun 1991 (R.S. Anderson# RSA 91-050) [LACM, CASENT0603567; EAPZ, CASENT0603699].

Geographic range. Guatemala, Mexico.

Diagnosis. Differing from R. isthmica in larger size (HW> 0.73 versus <0.69), and with propodeal tooth larger and more acute.

Description. Worker. HW 0.73–0.83 (n=12); mandible with two or three teeth on masticatory margin (can vary within individuals, with two teeth on one mandible and three teeth on the other), second tooth from base largest; subapical tooth with distinct reclinate denticle at base; subapical tooth about twice as long as apical tooth; intercalary teeth prominent, one closest to apical tooth about half as long as apical tooth; labrum trapezoidal, anterior lobes triangular, inner margins of lobes shallowly sloping to semicircular median notch; metanotal groove moderately to strongly impressed; propodeal tooth usually large and acute (shorter and obtuse on one specimen), infradental lamella evenly and shallowly concave; squamiform setae abundant on first gastral tergite, either uniformly covering entire tergite or covering at least 3/4 of posterior portion.

The queen and male are unknown.

Biology. This species occurs in cloud forest habitats, from 1400–2000 m elevation. All specimens are from Winkler or Berlese samples of sifted leaf litter. It is sympatric with R. isthmica at the type locality and with R. triumphalis on the slopes of Volcán Tacaná in Chiapas. At the type locality it was moderately abundant, occurring in 24 of 100 miniWinkler samples.

Etymology. Referring to its similarity to R. isthmica , differing mainly in larger size.

Figures

FIGURE 1. Diagrammatic representation of Rhopalothrix mandibles. A. R. andersoni, R. isthmica, R. megisthmica (part), R. therion. B. R. atitlanica, R. megisthmica (part), R. triumphalis. C. R. stannardi. D. R. nubilosa, R. subspatulata. E. R. weberi. F. R. apertor.