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Related to urostyle: keel bone


(Zoology) the bony rod forming the last segment of the vertebral column of frogs, toads, and related amphibians
[C19: from uro-2 + Greek stulos pillar]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈyʊər əˌstaɪl)

the fused vertebrae at the posterior end of the spinal column of tailless amphibians.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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References in periodicals archive ?
The caudal complex in crimson snapper consisted of the epurals, hypurals, preural arches, modified spines, urostyle, preural centra and caudal fin rays.
56*** 54-57 urostyle) Dorsal-fin origin 24*** 21-25 over vertebra Anal-fin origin 33*** 32-35 under vertebra B.
This process began at 6.1 mm; by 7.0 mm, 11 vertebrae were ossified, and by 7.7 mm all except for the last 8 vertebrae and the urostyle were ossified.
The Lano association comprises at least five taxa: one indeterminate albanerpetontid Allocaudata (represented by incomplete dentaries, axis, and fragmentary humeri), one indeterminate Caudata (atlas, trunk vertebrae, humerus), and at least three anurans: one indeterminate Discoglossidae (maxillaries, angulars, vertebrae, urostyle, humeri, and ilia), one indeterminate Palaeobatrachidae (angulars, presacral vertebra, synsacrums, humeri, and ilia), and at least one indeterminate anuran (maxillaries, humeri and ilia that could belong to one or several species) (Duffaud and Rage, 1999; Duffaud, 2000).
Dorsum and flanks separated by a narrow band, darker than the flanks, and with the same color intensity than spots on dorsum and extremities; this band extends from tympanum and upper eyelid to upper part of flanks, ending on the urostyle. Infraorbital region bears irregular cream spots.
Preliminary results indicate that the frog population in North Dakota exhibits a well-balanced sex ratio, healthy development of gonads, no malformations in the physical appearance or the bone structure, and a healthy snout to urostyle length.
Correlation Univariate Measurement coefficient F Significance Tibiofibula 0.6147 327.5 <0.0001 Femur 0.5620 273.7 <0.0001 ilium distance 0.3342 96.8 <0.0001 Sphenethmoid-ischium 0.2588 58.0 <0.0001 Calcaneus 0.2472 53.0 <0.0001 ilium angle 0.2044 36.2 <0.0001 Spheneth mold-snout 0.1913 31.7 <0.0001 Maxilla curvature 0.1577 21.55 <0.0001 Pubis 0.1470 18.72 <0.0001 Vertebral column 0.0616 3.3 0.0712 Urostyle -0.0445 1.7 0.1918 Otic 0.0017 0.002 0.9602