Ophiogomphus Selys, 1854 - Snaketails

Notes - Michigan Species List - Keys - References
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Page last updated: 01/17/2017

Notes on the Michigan larvae of Ophiogomphus

Six of the approximately 17 species of Ophiogomphus known from North America have been reliably recorded in Michigan (see below). O. rupinsulensis, probably our most common ophiogomphid, is widely distributed throughout the state. O. carolus and O. colubrinus are widely distributed in the UP and the northern LP. O. aspersus is known from three widely scattered records in the LP and one record from Gogebic County in the western UP. New larval records exist for O. anomalus (Iron Co.) and O. howei (Escanba Co.) in the UP (D. Cuthrell, Michigan Natural Features Inventory, pers. comm.). A species only recently described, O. susbehcha (Vogt and Smith 1993), may be encountered in the western part of the UP and is included in the key below (T. Vogt, pers. comm.). Except for morphologically distinctive larvae of O. anomalus and O. howei (see key below), reliable species-level identification usually works only for mature specimens.

A new key to the Ophiogomphus of the Western Great Lakes appeared in 2016, with the paper by Smith and Tennessen should be useful for identifying the larvae of what has sometimes been called "Awfulgomphus."

Larval Ophiogomphus are common in clean rivers and streams (rarely from wave-swept shores of lakes), particularly where water quality has not been degraded by changes to flow or by siltation from channelization or agricultural activities. Frequently found in sand and/or gravel substrates, larvae lie submerged within the substrate or underneath rocks or boulders. Sometimes more than one species is found together in one microhabitat. Vogt and Smith 1993 found larvae of O. howei and O. rupinsulensis together with a new described species,O. susbehcha, in a large Wisconsin river. Larvae of the three species were found in deep (1m), swiftly flowing water among sand and gravel substrate interspersed with large boulders. I (EB) have found O. rupinsulensis in similar habitat in the Pine River, Marquette Co. (26 June 1997), from which a large number of larvae had just emerged to transform on the vertical surface of a bridge support. Walker (1958) remarks that O. aspersus and O. colubrinus prefer clear, cold rapid streams with gravelly or sandy beds, whereas O. rupinsulensis appears more tolerant of warmer streams with somewhat more silting. Kennedy and White (1979), who first described the larval form of O. howei from specimens collected in Pennsylvania and Virginia, found individuals in sand and gravel substrate in clean, swiftly flowing waters. Tennessen (1993) found larvae in medium to large (10-100m width) rivers with predominately gravel and sand substrates interspersed with large rocks and boulders. He also noted the lack of disturbance due to forestry and agricultural habitats in sites that O. howei were found. Based on these Wisconsin populations, emergence in Michigan probably occurs in very late May through June. Kennedy and White (1979) also describe this species' emergence and nymphal diet: "The nymphs were observed climbing out of the river and up vertical mud banks. Emergence either occurred while clinging to the exposed mud bank or in the grassy vegetation on the top of the bank. Emergence occurred between early morning and early afternoon... Foregut contents of 5 O. howei mid-instar nymphs..revealed water mites...mayfly nymphs...and midge larvae. Two distinct size classes...were collected from the New River suggesting a 2 year life cycle."

WWW-Links on the ecology or biology of larval Ophiogomphus:
Ophiogomphus of NE North America >>http://www.hsrl.rutgers.edu/NY.ophio.html
Consevation status and habitat info on O. howei in Maine, USA >>http://wlm13.umenfa.maine.edu/randy/www/tande/group/PSTail.html
Brief habitat notes from Ottawa, Ontario >> http://www.cyberus.ca/~jdsankey/odon2.html

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Michigan Species List of Ophiogomphus

Map 1 Map 2Map 3
Map 4Map 5Map 6
County distribution for the Michigan species of
Ophiogomphus
Click on map for a larger image

Ophiogomphus anomalus Harvey, 1898 - Extra-striped Snaketail - Map 1
Ophiogomphus aspersus Morse, 1895 - Brook snaketail - Map 2
Ophiogomphus carolus
Needham, 1897 - Riffle snaketail - Map 3
Ophiogomphus colubrinus
Selys, 1854 - Boreal snaketail - Map 4
Ophiogomphus howei
Bromley, 1924 - Pygmy snaketail - Map 5
Ophiogomphus rupinsulensis
(Walsh, 1862) - Rusty snaketail - Map 6
*
Ophiogomphus susbehcha Vogt and Smith, 1993 - Susbehche snaketail

* not yet recorded in Michigan, but may be encountered in the western half of the UP

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Key to Mature Larvae of Michigan Ophiogomphus
(Modified from
Walker 1933, Walker 1958 and Carle 1992)

1a. Middorsal abdominal hooks vestigial or lacking on all segment (Figures 1a1, 1a2) - 2

Fig. 1a1 Fig. 1a2
Fig. 1a1:
O. howei exuvia (6x dorsal view), from New River, Grayson Co., WV, collected by J. H. Kennedy on 07 May 1977. UMMZODO-0809.
Fig. 1a2: Ibid., (6x, lateral view).

1b. Middorsal abdominal hooks well-developed on some abdominal segments (Fig. 1b1) - 3

Fig. 1b1
Fig. 1b1:
Ophiogomphus rupinsulensis larva (6x, lateral view), collected from Hearted River, Luce Co., MI, by the Institute of Fisheries Research on 18 October 1950. UMMZODO-0870.


2a.(1b). Lateral spines present on Ab7 (Figure 2a1); base of Ant4 broad, appearing to completely cap that of Ant3 (Figure 2a2); cerci about 0.5x the length of epiproct (Figure 2a3); large, mature specimens 27-32 mm - O. susbehcha

Fig. 2a1Fig. 2a2
Fig. 2a3
Fig. 2a1:
O. susbehcha exuvia (12.5x, lateral view), from St. Croix River, Burnett Co., WI, collected by T. E. Vogt on 30 May 1990.
Fig. 2a2: Ibid., (25x, dorsal view).
Fig. 2a3: Ibid., (12.5x, dorsal view).

2b. Lateral spines absent or vestigial on Ab7 (Figure 2b1); base of Ant4 narrow, much narrower than that of Ant3 (Figure 2b2); cerci > 0.7x length of epiproct (Figure 2b3); small, mature specimens 19-23 mm - O. howei

Fig. 2b1 Fig. 2b2
Fig. 2b3
Fig. 2b1:
O. howei exuvia (12.5x, dorsal view), from New River, Grayson Co., WV, collected by J. H. Kennedy on 07 May 1977. UMMZODO-0809.
Fig. 2b2: Ibid., (25x, dorsal view).
Fig. 2b3: Ibid., (25x, dorsal view).

Back to beginning of key


3a.(1b). Ant4 broadly capping distal end of Ant3, Ant3 not distally narrowed (Figure 3a1) - O. anomalus

Fig. 3a1
Fig. 3a1:
Ophiogomphus anomalus larva (25x, dorsal view), from Paint River, Iron Co., MI, collected by D. L. Cuthrell and D. A. Hyde (Michigan Natural Features Inventory) on 19 June 1996. UMMZODO-2029.

3b. Ant4 minute, considerably narrower than Ant3, Ant3 distally narrowed (Figure 3b1) - 4

Fig. 3b1
Fig. 3b1:
O. carolus larva (25x, dorsal view), from Paint River, Iron Co., MI, collected by D. L. Cuthrell and D. A. Hyde (Michigan Natural Features Inventory) on 19 June 1996. UMMZODO-2032.
Back to beginning of key


Note: Ab10 is often telescoped within, and partially concealed by, Ab9. To accurately measure the middorsal length of Ab10, it may be necessary to gently extend this portion of the abdomen out so that the anterior border of Ab10 is visible. This can be done by gently but firmly grasping with forceps both Ab9 and Ab10, and pulling these apart until the anterior border of Ab10 becomes visible. Often, particulate matter accumulates along the border, and this should be cleaned with a fine haired brush.

4a.(3b). Length of cerci 2x the middorsal length of Ab10, their basal width not less than 0.5x the length of their dorsal edge, and < 2.0x their middle width; cuticular granules coarse and deeply pigmented (Figure 4a1); middorsal hooks on Ab7-9 heavy, in lateral view rapidly acuminate (Figure 4a2) - 5

Fig. 4a1Fig. 4a2
Fig. 4a1:
Ophiogomphus carolus larva (12.5x, dorsal view), collected from Paint River, Iron Co., MI, by D. L. Cuthrell and D. A. Hyde (Michigan Natural Features Inventory) on 19 June 1996. UMMZODO-2032.
Fig. 4a2:
Ophiogomphus rupinsulensis larva (6x, lateral view), collected from Hearted River, Luce Co., MI, by the Institute of Fisheries Research on 18 October 1950. UMMZODO-0870.

4b. Length of cerci 2.5x the middorsal length of Ab10, their basal width < 0.5x the length of their dorsal edge, and > 2.0x their middle width; cuticular granules fine and not much darker than surrounding area (Figure 4b1); middorsal hooks on Ab7-9 slenderer, in lateral view more gradually tapered (Figure 4b2) - 6

Fig. 4b1 Fig. 4b2
Fig. 4b1:
Ophiogomphus colubrinus larva (12.5x, dorsal view), collected from Mio Pond, Osceola Co., MI, by C. L. Hubbs and T. H. Langlois on 26 July 1924. UMMZODO-2113.
Fig. 4b2: Ibid., (6x, lateral view).

Back to previous couplet (2); Back to beginning of key


5a.(4a). In lateral view middorsal hooks on Ab7-9 appressed, those on 8 and 9 low and nearly flat (Figure 5a1); Ant3 spatulate, length about 2.0-2.5x that of width (Figure 5a2); cerci about 0.61-0.71x that of epiproct; dorsal knob on Ab2 a rounded knob, somewhat backwards aslant (Figure 5a3) - O. carolus

Fig. 5a1 Fig. 5a2
Fig. 5a3
Fig. 5a1:
Ophiogomphus carolus larva (12.5x, lateral view), collected from Paint River, Iron Co., MI, by D. L. Cuthrell and D. A. Hyde (Michigan Natural Features Inventory) on 19 June 1996. UMMZODO-2032.
Fig. 5a2: Ibid., (25x, dorsal view).
Fig. 5a3: Ibid., (12.5x, lateral view).

5b. In lateral view middorsal hooks on Ab7-9 raised, convexly arched (Figure 5b1); Ant3 enlongate, length about 2.5-3.0x that of width (Figure 5b2); cerci about 0.70-0.75x that of epiproct; dorsal knob on Ab2 more upright - O. rupinsulensis

Fig. 5b1 Fig. 5b2
Fig. 5b1:
Ophiogomphus rupinsulensis larva (12.5x, lateral view), collected from Hearted River, Luce Co., MI, by the Institute of Fisheries Research on 18 October 1950. UMMZODO-0870.
Fig. 5b2: Ibid., (12.5x, dorsal view).

Back to previous couplet (3a); Back to beginning of key


6a.(4b). Distal lateral margin of prementum of labium barely divergent to parallel (Figure 6a1); dorsal hooks on Ant 8 and 9 apically acutangulate or rectangulate in dorsal view (Figure 6a2); length of lateral spines on Ant8 and 9 equal (Figure 6a3) - O. colubrinus

Fig. 6a1 Fig. 6a2
Fig. 6a3
Fig. 6a1:
Ophiogomphus colubrinus larva (12.5x, ventral view), collected from Mio Pond, Osceola Co., MI, by C. L. Hubbs and T. H. Langlois on 26 July 1924. UMMZODO-2113.
Fig. 6a2: Ibid., (12.5x, dorsal view).
Fig. 6a3: Ibid., (12.5x, dorsal view).

6b. Distal lateral margin of prementum of labium slightly convergent (picture); dorsal hooks on Ab8 and 9 apically obtusangulate in dorsal view (picture); lateral spines on Ab9 smaller than those on Ab8 (picture) - O. aspersus
Back to previous couplet (3b); Back to beginning of key

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References

Bromley, S. W. 1924. A new Ophiogomphus (Aeschnidae: Odonata) from Massachusetts. Entomology News 35(10):343-344.

Carle, F. L. 1992. Ophiogomphus (Ophionurus) australis spec. nov. from the Gulf Coast of Louisiana, with larval and adult keys to American Ophiogomphus (Anisoptera: Gomphidae). Odonatologica 21(2):141-152.

Harvey, F. L. 1898. Contributions to the Odonata of Maine II. Entomological News 9(3):59-64.

Kennedy, J. H., and H. B. White. 1979. Description of the nymph of Ophiogomphus howei (Odonata: Gomphidae). Proceedings of the Entomological Society of Washington 81(1):64-69.

Morse, A. P. 1895. New North American Odonata. Psyche 7:207-211.

Needham, J. G. 1897. Preliminary studies of N. American Gomphinae. The Canadian Entomologist 29(7):164-168, (8):181-186.

Selys-Longchamps, M. E. de. 1854. Synopsis des Gomphines. Bulletin de l'Académie royale des Sciences de Belgique 21:23-114.

Smith, W.A. and K.J. Tennessen. 2016. Description of the nymph of Ophiogomphus smithi (Odonata: Gomphidae), with a key to the species of Ophiogomphus in the Western Great Lakes region. The Great Lakes Entomologist. 49(1-2):78-97.

Tennessen, K. J. 1993. New distribution records for Ophiogomphus howei (Odonata: Gomphidae). The Great Lakes Entomologist 26(3)245-249.

Vogt, T. E. and W. A. Smith. 1993. Ophiogomphus susbehcha spec. nov. from North Central United States (Anisoptera: Gomphidae). Odonatologica 21(2):141-152.

Walker, E. M. 1933. The nymphs of the Canadian species of Ophiogomphus Odonata, Gomphidae. The Canadian Entomologist 65:217-229.

Walker, E. M. 1958. The Odonata of Canada and Alaska, Vol. 2. University of Toronto Press: Toronto. xii + 318.

Walsh, B. D. 1862. List of the Pseudoneuroptera of Illinois contained in the cabinet of the writer, with descriptions of over forty new species, with notes on their structural affinities. Proceedings of the Academy of Natural Sciences Philadelphia 14:361-402.

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