Ephemeroptera: Heptageniidae of Gunnison County, Colorado
Nixe criddlei(McDunnough) 1927
Updated 1 Jan 2012
NotesRecently moved to the genus Ecdyonurus by McCafferty in 2004.
ReferencesColletti PJ; Blinn DW; Pickart A; Wagner VT. 1987 Influence of different densities of the mayfly grazer Heptagenia criddlei on lotic diatom communities. Journal of the North American Benthological Society 6(4):270-280. PDF
Flowers RW. 1980 Two new genera of Nearctic Heptageniidae (Ephemeroptera). Florida Entomologist 63:296-307. PDF
Splits and describes the new genera Leucrocuta and Nixe from Heptagenia.
McCafferty, W. P. 2004. Contribution to the systematics of Leucrocuta, Nixe, and related genera (Ephemeroptera: Heptageniidae). Transactions of the American Entomological Society 130(1): 1-9.
The author moves Nixe criddlei into the genus Ecdyonurus because it has all the features of the Ecdyonurus simplicioides species group. Quote from page 3: "For the purposes of recognizing Ecdyonurus in North America, i.e., the simplicioides species group of Ecdyonurus, especially from the closely related genera Leucrocuta and Nixe, it may be diagnosed as having generally plesiotypic larvae with well-developed male eyes, an unmodified pronotum, a gill tuft with two or more filaments present at base of gill lamellae 6 (usually well-developed), and the three caudal filaments with well-developed interfacing setae; and in adults, as having proximate male eyes in addition to having penes (e.g., Fig 98 [Traver 1935], Fig. 4g [Demoulin 1964], Figs 103, 106 ;Jensen 1966]) with divergent lobes that have spines present ventrally, a medially extended lateral sclerite dorsally, narrowly attenuate titillators, and that lack developed dorsolateral spines." He notes that the genera Ecdyonurus, Leucrocuta and Nixe are very similar.
McCafferty,WP; Durfee,RS; Kondratieff,BC 1993 Colorado mayflies (Ephemeroptera): an annotated inventory. Southwestern Naturalist 38 3, 252-274. PDF
Discusses this species as Nixe criddlei. Quote from page 261: "It is likely that some of the Heptagenia spp. reported from the upper Gunnison River drainage system by Argyle and Edmunds (1962) are referable to this species."
McDunnough,J 1927 A new Heptagenia from the Yellowstone Region (Ephemeroptera). Canadian Entomologist 59:261.
Described as Heptagenia criddlei.
Zuellig,RE; Kondratieff,BC; Rhodes,HA 2002 Benthos recovery after an episodic sediment release into a Colorado Rocky Mountain river. Western North American Naturalist 62 1, 59-72.
Discusses this species as Nixe criddlei.