Aquatic Insects of Michigan
by Ethan Bright, Museum of Zoology Insect Division and School of Natural Resources and Environment
Erythemis Hagen, 1861 (Libellulidae) (Pondhawks) of Michigan - Identification
Of the 8 species of this primarily Neotropical genus found north of Mexico, one widely distributed species - Erythemis simplicicollis (Say, 1839) - occurs in Michigan, most commonly in the southern half of the Lower Peninsula.
Adults are moderate in size, greenish in appearance. Clear-winged, with a greenish face and black and green banded abdomen that fades in aging males. Legs are spiny. Nymphs are small and stocky larvae, often collected from loose, fine organic detritus in which they conceal themselves. Nymphs are easily distinguished from other Michigan libellulid nymphs by the decurved cerci and paraprocts, their prominently striped green and brown eyes (this striping remains noticeable in specimens preserved in alcohol for long periods of time), lack of mid-dorsal hooks and lateral spines on the abdomen, and long, spiny legs.
Erythemis simplicicolis is a common resident of marshy, often eutrophic ponds and lakes and sometimes slow sections of streams. Emergence in our area occurs usually from late-May through June. I have reared nymphs collected from Half-Moon Lake in Livingston Co., southern Michigan, in mid-April that emerged as adults in late May. In southern Michigan, larvae may be multivotine or evidenced two different populations. Ed Kormondy also collected two size classes of larvae on 15 September 1953 from South Lake in Washtenaw Co., clearly indicating two size classes: one specimen appeared ready to emerge (enlarged thorax, wing pads enlarged), another very small specimen that was clearly immature. Similarly to Perithemis tenera (Morin 1984, Wissinger 1988), voltinism may be influenced by fish predation and food resources.
Taxonomic references: Needham et al. 2010, Paulson 2011, Walker and Corbet 1975
Page created: July 17, 1998 - Last updated: February 19, 2017 (EB)