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Title:A Review of the Sunfishes of the Current Genera Apomotis, Lepomis, and Eupomotis, with Particular Reference to the Species Found in Illinois
Author(s):Richardson, R.E.
Illinois species
Illinois State Laboratory of Natural History
Abstract:During the progress of studies on material from the large collection of Illinois sunfishes belonging to the Illinois State Laboratory of Natural History, a striking and, as it appeared later, fundamental difference in form was observed between the lower pharyngeals of specimens oiLeponiis pallidus (Mitchpill) and Eupomotis gihhosus (Linnaeus). These bones in the first species were found to be comparatively light, flattened dorso-ventrally, and always narrow, the width in the length of 28 the toothed portion of the bone ranging from 2.9 to 3.4 and averaging more than 3 in twenty measured specimens whose length ranged from 2f to 6 inches. The inner angle {La.) is quite obtuse, 120° to 140°, and the outer margin {o.m.) is straight or slightly inbent from the tip of the posterior spur {p. sp.) to the anterior extremity {mit.) of the bone. The lower pharyngeals of Eupomotis gibbosus are deep and broad, with inferior and lateral prominences, never being flattened or hollowed out underneath as in L. paUidiis. Measurements made on twenty specimens, from 2| to 6 inches in length, show a variation of only 1.9 to 2.5 (average 2.17) in the ratio of width to length of the toothed portion, and a range of 95° to 111° in the inner angle. The outer margin of the pharyngeal in this species presents a double curve, with a moderate sinus situated posteriorly, immediately in front of the spur, and a more or less decided anterior arcuation, margining a lateral ledge-like prominence. The spur is directed more or less definitely outward, rather than backward as in L.paUidus. The differences between the teeth of these two species were found to be as hitherto described, those of E. gibbosus being short and heavy and either very blunt or entirely paved, while those of L. palUdus are long and comparatively slender, with more or less acuminate tips.
Issue Date:1904
Publisher:Champaign : Illinois Natural History Survey
Series/Report:Illinois Natural History Survey Bulletin; v. 007, no. 03
Rights Information:Copyright 2009 University of Illinois Board of Trustees. All rights reserved.
Date Available in IDEALS:2014-10-06

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