LA SELVA ODONATE HABITATS

LOWLAND STREAMS

Small clay-bottomed lowland streams at La Selva (such as the Quebrada El Surá) support a limited odonate fauna, including Hetaerina miniata, Heteragrion erythrogastrum, Palaemnema paulirica, and Epigomphus tumefactus.

PIEDMONT STREAMS

At slightly higher elevations, La Selva streams (such as the Quebrada La Esquina) have a faster flow and often tumble over boulders and gravel. Different odonates inhabit these streams, including Heteragrion albifrons, Philogenia carrillica, Perissolestes spp., Argia adamsi, A. cuprea, Brechmorhoga spp., and Macrothemis spp

RIO PUERTO VIEJO

This wide river with moderate current and rock and mud bottom supports an odonate fauna different from that of its tributary streams, including Hetaerina titia, Argia pulla, A. translata, numerous gomphids (including Archaeogomphus furcatus, Aphylla sp., Phyllocycla volsella), Dythemis sterilis, Elasmothemis cannacrioides, and Macrothemis inacuta.

MARSHY SWAMPS

There are several of these at La Selva, one quite near the field station, and they appear to support a very diverse odonate fauna. They form clearings into which sufficient sunlight penetrates to have a marshy situation with extensive tall grass beds and some open water in the center, usually surrounded by Spathiphyllum at the edges. During periods of high water, the forest itself is flooded, providing swamp conditions. Lestes scalaris, Psaironeura selvatica, Acanthagrion speculum, Chrysobasis lucifer, Leptobasis vacillans, Metaleptobasis bovilla, Coryphaeschna apeora, C. diapyra, Gynacantha gracilis, G. tibiata, Triacanthagyna satyrus, Anatya normalis, Cannaphila insularis, Erythemis haematogastra, 5 species of Erythrodiplax, 7 species of Micrathyria, Nephepeltia phryne, Perithemis electra, and Zenithoptera americana are all characteristic of this habitat.

STREAM-SWAMPS

Some small streams flow slowly through the forest and seem as much like narrow swamps as streams. Common inhabitants include Psaironeura remissa, Argia indicatrix, A. popoluca, and Epigomphus armatus. An undescribed all-black species of Palaemnema lives in this habitat.

FOREST INTERIOR

Scattered throughout the forest interior can be found species that breed in nearby streams or swamps, including especially females of Heteragrion, Gynacantha, and Triacanthagyna. Some species occur independent of permanent water, for example pseudostigmatids (including Mecistogaster modesta and Megaloprepus caerulatus), Gynacantha membranalis, Libellula herculea, Orthemis cultriformis, and Uracis fastigiata that breed in tree holes, bromeliads, or temporary puddles on the forest floor. Small sunny tree gaps within the forest are likely to have one or more foraging pseudostigmatids ("helicopters"), probably the most spectacular of La Selva's odonates.

FOREST CLEARING

Many females of forest-based species feed in sunny clearings, and fewer males of the same species. They include Hetaerina spp., pseudostigmatids that come out of the forest to feed around the edges, Argia spp., and many libellulids, including Erythrodiplax spp., Libellula herculea, Orthemis discolor, and Uracis imbuta. Species that feed in flight, including at least 2 species of Brechmorhoga, 5 species of Macrothemis, and Miathyria simplex, utilize these clearings commonly.