Micrathyria sympriona spec. nov., a new dragonfly from Ecuador and Peru (Anisoptera: Libellulidae)

Micrathyria is a neotropical group of42 currently recognized species (BRIDGES, 1994), although the genus is in need of revision. Recently described species include ringueleti (RODRIGUES CAPITULO, 1988), venezuelae (DE MARMELS, 1989), caerulistyla (DONNELLY, 1992), and divergens, dunklei, occipita, and pseudeximia (WESTFALL, 1992). DUNKLE (1995) described a new subspecies of mengeri. The new species described here is from southern Ecuador and Peru. When I first looked at the thoracic color pattern and hamules in the field, I assumed they were M. laevigata Calvert. When J.J. Daigle and Iexaminedthem more closely in the laboratory, we noticed the very different cerci and suspected they represented an undescribed species. Several species in addition to M. laevigata possess hamules in which the outer arms extend anteriorly past the anterior laminae and bear stout spines on the anterior margin (hereafter referred to as the M. didyma group). I compareit in detail to M. hypodidyma Calvert, which it closely resembles in morphology and color pattern, and distinguish it from other species in the group. In the collecting data, the names of the collectors are abbreviated as follows: JJD (Jerrell J. Daigle), The new sp. (holotype 6 , allotype 9: Ecuador, Zamora Chinchipe prov., grassy marsh 5.5 km SE of Zamora, ca 3000 ft, 4°10’S, 78°56’W, 5-XI-1997; deposited at FSCA, Gainesville, FL, USA) is described and compared with M. hypodidyma Calvert. M. sympriona differs in the low, laterally rounded transverse ridge on the venter of abdominal segment 1 which bears 0 to 3 widely spaced black denticles on each side of