The 113 species of dragonflies so far recordedin Michigan are divided into 7 families and 36 genera. The larvae ofAnisoptera are distinguished from that of Zygoptera by a more robustshape, such that the thorax and abdomen are generally wider than thehead, and that respiration chiefly occurs by expansion andcontraction of abdominal muscles that move water in and out of therectal chamber across gills located within this structure. This alsopermits larvae to achieve rapid bursts of speed in the water. Larvaeof Michigan Anisoptera inhabit just about every type of aquaticecosystem in the state, from the largest of lakes to the smallest bogpool, from the very small woodland seeps to the largest of ourrivers. Our species of Cordulegaster generally are found only inseeps and streams, and the only species of Petaluridae found inMichigan - Tachopteryx thoreyi- probably is found only in leafymaterial in the upper portions of forested seeps, and is probably ouronly odonate that can breathe air (semiterrestrial).
The similarity in morphology among the larvae of Libellulidae,Corduliidae and Macromiidae has led some to group these assubfamilies in Libellulidae. As of yet, no one morphologicalcharacter has been found to reliably separate larvae of Corduliidaefrom Libellulidae, although characters suggested by
Fig. 1: Ophiogomphusrupinsulensis larva (6x,lateral view), from the Salmon-Trout River, Marquette County,Michigan, by M. F. O'Brien on 21 June 1997. Fig. 2:
1b. Prementumand palpal lobes forming spoon-shaped structure
Fig. 3. Cordulia shurtleffi larva (6x, lateral view), collected from Lake Genevieve(near Ann Arbor), Washtenaw County, Michigan by M. F. O'Brien on 05April 1998. UMMZODO-1896.
Fig. 4 Fig. 5 Fig. 6
Fig. 4: Ophiogomphusrupinsulensis larva (dorsalview, 12.5x), from Salmon-Trout River, Marquette Co., Michigan,collected by M. F. O'Brien, on 21 June 1997, UMMZODO-1972; Fig. 5-6:Dromogomphusspinosus larva (both 12.5x,ventral view), from Third Sister Lake, Washtenaw Co., Michigan,collected by F. Locke in July, 1940, UMMZODO-0562.
2b. Antennae6- and 7-segmented (Fig. 7); pro- and metatarsi tarsi 3-segmented(Fig. 8); ligula with a median cleft (Fig. 9) -
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3b. Antennalsegments slender and bristle-like (picture); prementum widest indistal half, then much narrower in basal half or more (picture);abdomen without
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Fig. x: Cordulegaster maculata larva (6x, ventral view), from Sunset Creek, Iron Co.,Michigan, collected by D. Cuthrell and D. Hyde (Michigan NaturalFeatures Inventory) on 14 June 1996. UMMZODO-1576.
4b. Distaledge of lateral lobe entire, or with even-sized dentations, withassociated setae (picture); ligula not as above (picture) -5
Fig.x Fig. x
Fig. x-x: Libellulaluctuosa larva (12.5x,ventral view), from Pond at Clear Creek (Norris Dam), Anderson Co.,Tennessee, collected by M. Wright on 21 July 1946.UMMZODO-1994.
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Fig. xa: Macromiaillinoiensis larva (Figs.xa-xb, 6x dorsal view; Fig. xc, 6x ventral view), from an unknownlocality in Alpena Co., Michigan, collected by C. L. Hubbs on 30August 1925. UMMZODO-1219. Fig. xb: Macromia illinoiensis larva (6x, dorsal view), same specimen as Fig. xa. Fig.xc: Macromiaillinoiensis larva, (6x,ventral view), same specimen as in Fig. xa.
5b. Headwithout frontal horn positioned between antennae (Fig. x), andmetafemur not
Fig. xa: Epithecaspinigera larva (6x, dorsalview), from an unknown locality in Montmorency Co., Michigan,collected by C. L. Hubbs in July, 1925. UMMZODO-0310. Fig. xb:Epithecaspinigera larva (12.5x,dorsal view), same specimen as in Fig. xa.
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Fig.xa Fig. xb Fig. xc Fig. xd
Fig. xa: Epithecacynosura larva (25x, ventralview), from Hess Pond, Columbus, Franklin Co., Ohio, collected by M.Wright on 26 May 1939. UMMZODO-2015. Fig. xb:
6b. Distaledge of lateral lobe of labium generally with crenations less thanone-fourth as wide, or obsolete (fig. xa); cerci usually less thanone-half as long as epiproct (fig. xb); abdomen distally more tapered(fig) -
Fig. xa Fig. xb Fig. xc
Fig xa-c: Libellulaluctuosa larva (6x, dorsalview), from Pond at Clear Creek (Norris Dam), Anderson Co.,Tennessee, collected by M. Wright on 21 July 1946. UMMZODO-1994. Fig.xb: Libellulaluctuosa larva (12.5x, dorsalview), same specimen as in Fig. xa. Fig. xc:
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7b. Lateralspine of Ab8 as long as middorsal length of Ab9, or longer (Fig. x) -
Fig. x: Pantalahymenea larva (6x, dorsalview), from Marble Cliffs Pond, Columbus, Franklin Co., Ohio,collected by M. Wright on 03 August 1939. UMMZODO-1540.
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Gloyd, L. K. 1959.Elevation of the Macromia group to family status (Odonata).Entomological News
Walker, E. M.,and P. S. Corbet. 1975. The Odonata of Canada and Alaska, Vol. 3.University of Toronto Press: Toronto. xvi +308 p.
Westfall,M. J., Jr. and K. J. Tennessen. 1996. Odonata, pp. 164-211.In AnIntroduction to the Aquatic Insects of North America, 3rd Ed. R. W.Merritt and K. W. Cummins (eds.) Kendell/ Hunt Publishing Company:Dubuque, Iowa.
Wright, M.,and A. Peterson. 1944. A key to the genera of Anisopterous dragonflynymphs of the United States and Canada (Odonata, SuborderAnisoptera). Ohio Journal of Science44(4):151-166.