Aquatic Insects of Michigan

by Ethan Bright, Museum of Zoology Insect Division and School of Natural Resources and Environment
University of Michigan

Potamantidae (Hacklegill Mayflies) of Michigan - Identification

Introduction

These are mayflies of medium- to large-sized rivers where the larvae. Unlike most of the Ephemeroidea group, Anthopotamus nymphs generally are not active burrowers, but rather sprawl among the gravel and rocks of riffles under moderate current, or sometimes under logs and larger rocks (McCafferty 1975). [Under construction].

The two species of this family are included in the genus Acthopotamus, which was erected by McCafferty and Bae (1990) for Neartic species previously included in Potamanthus Pictet.

Adults (Imagoes, adapted from Burks 1953)

1a	a. Abdomen usually entirely unmarked, occasionally each abdominal segment with a faint, minute, pink spot on either side	Anthopotamus myops (Walsh)
	b. Crossveins in fore wing hyaline in each sex
	c. Compound eye of male small, greatest longitudinal length less than that of the median longitudinal length of the head
1b	a. Abdomen with large, well-marked, lateral salmon-pink spots	Anthopotamus verticis (Say)
	b. Crossveins in fore wing hyaline, but sometimes with a few anterior crossveins black
	c. Compound eye of male large, greatest longitudinal length as long or longer than that of the median longitudinal length of the head

Mature Nymphs
(adapted from McCafferty 1975)

1a	a. Mandibular tusks more or less evenly rounded along the lateral margins, and spinal armature scattered over most of the dorsal surface	Anthopotamus myops (Walsh)
	b. Lateral areas of abdominal tergites moderately patterned with pale maculations
	also: Ground color dark, cinnamon-brown, never with any tinge of reddish or reddish-brown
1b	a. Mandibular tusks somewhat constricted and devoid of spinal armature in the distal half	Anthopotamus verticis (Say)
	b. Lateral areas of abdominal tergites not, or only very slightly patterned, with pale maculations
	also: Dorsum of abdomen with longitudinal, median, pale markings, which are interrupted at the middle third of the tergites

References

Burks BD. 1953. The mayflies, or Ephemeroptera, of Illinois. Illinois Natural History Survey Bulletin 26(1):1-216.
McCafferty WP, Bae YJ. 1990. Anthopotamus, a new genus for North American species previously knon as Potamanthus (Ephemeroptera: Potamanthidae). Entomological News 101:200-202.
McCafferty WP. 1975. The burrowing mayflies of the United States (Ephemeroptera: Ephemeroidea). Transactions of the American Entomological Society 101:447-504.

Page created: February 28, 2004; Last edited: November 06, 2013 (EB)