Aquatic Insects of Michigan

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

Metretopodidae of Michigan - Identification

Adults

1a	One pair of cubital intercalaries present	Metretopus borealis (Eaton)
	note: rare
1b	Two pairs of cubital intercalaries present	Siphloplecton Clemens, 2
	note: widespread
2a(1b)	a. Crossveins in entire forewing brown	Siphloplecton basale (Walker)
	b. Hindwing with entire basal third shaded with brown
2b	a. Crossveins in forewing brown only near costal margin, and along stem of R4+5	Siphloplecton interlineatum (Walsh)
	b. Hingwing with brown shading confined to area around bases of C, Sc, and R

Mature Nymphs

1a	a. Margins of protarsal claws densely covered with spines (> 30) that are only slightly smaller than the short terminal spines	Metretopus borealis (Eaton)
	b. Outer margin of Ab4 gill with 2-7 stout spines in addition to small setae
	note: rare
1b	a. Margins of protarsal claws sparsely covered with spines (< 20) that are more slender than the long terminal spines	Siphloplecton Clemens, 2
	note: widespread
2a(1b)	a. Median ventral stripe of abdomen continuous, uninterrupted	Siphloplecton basale (Walker)
	b. Mesotarsal claw 10x as long as wide at base
2b	a. Median ventral stripe of abdomen interrupted at each intersegmental suture	Siphloplecton interlineatum (Walsh)
	b. Mesotarsal claw 7-8x as long as wide at base

Page created: June 16, 2003; Last edited: November 06, 2013 (EB)