Shape Analysis of Frasnian Species of the Late Devonian Conodont Genus Palmatolepis

1993 ◽  
Vol 67 (S32) ◽  
pp. 1-35 ◽  
Author(s):  
Gilbert Klapper ◽  
C. T. Foster

Multielement taxonomy and shape analysis have led to substantial revisions in the taxonomic concepts of 13 Frasnian species of Palmatolepis, which previously have been based largely on visual discrimination of the Pa elements. Septimembrate apparatuses have been recognized in three species and diagnostic Pb elements are associated with the Pa elements of eight others. The multielement reconstructions thus derived provide the a priori classification that is tested by the canonical variate analysis of the outlines of the Pa elements. The outlines are digitized from a TV image and quantified by calculating mean tangent angles within a specified number of intervals between landmarks. The mean tangent angles for each interval are the variables used in the canonical variate analysis. In a series of comparisons limited to three species each, all 13 species separate into isolated clusters that are completely congruent with the a priori groups based, with two exceptions, on multielement taxonomy. Thus, shape analysis provides a rigorous separation of closely similar species that have been difficult to distinguish by visual discrimination of the Pa elements. Shape analysis is treated herein as an integral part of the systematic descriptions. Newly described species are P. bohemica, P. boogaardi, P. luscarensis, and P. muelleri. The new taxonomic concepts lead to significant revisions in the biostratigraphic ranges of a number of species of Palmatolepis involved in the zonation and graphic correlation of the Frasnian Stage.

2019 ◽  
Vol 10 (2) ◽  
pp. 304-313
Author(s):  
Patrick T. Kroboth ◽  
Duane C. Chapman ◽  
Robert A. Hrabik ◽  
David A. Neely

Abstract Black Carp Mylopharyngodon piceus and Grass Carp Ctenopharyngodon idella are morphologically similar species native to eastern Asia and imported to North America as biological control organisms. Preferred identification methods are coloration and pharyngeal tooth form. Grass Carp possess serrated teeth and Black Carp molariform teeth. Examination of pharyngeal teeth causes extensive damage to a specimen and is labor and time intensive. Coloration can vary within a species and fades with preservation. We present a suite of external characteristics consisting of a truss network canonical variate analysis of distance measurements among landmarks on the lateral view of the head of each fish, the ratio of head length to mouth width, the visible presence of the premaxilla viewed dorsally with the mouth fully closed, and anterior lateral line angles among scales. Canonical variate analysis suggested that Grass Carp have a deeper head at the preoperculum and Black Carp a more elongate head relative to the preoperculum and eye. Comparisons of head length to mouth width ratio, visibility of the premaxilla dorsally with the mouth fully closed, and anterior lateral line angles all served as external characteristics of species, but outliers were present for each method. Because of the plastic morphology of wild populations, we suggest that a combination of characters be applied for identification.


1984 ◽  
Vol 62 (12) ◽  
pp. 2519-2526 ◽  
Author(s):  
C. G. van Zyll de Jong

Crania and bacula of five taxa of small-footed bats of the leibii group, comprising two currently recognised species, Myotis californicus and M. leibii, were studied to elucidate their interrelationships. Canonical variate analysis of 14 cranial measurements shows the existence of three distinct nonoverlapping clusters corresponding to (i) M. californicus, (ii) M. I. ciliolabrum and M. I. melanorhinus, and (iii) M. I. leibii. The results of the morphometric analyses do not support the claim that M. I. leibii and M. I. melanorhinus intergrade in Oklahoma. The taxonomic interpretation of the results is that the western forms of M. leibii represent a separate species M. ciliolabrum (Mcrriam). The bacula of the taxa studied lack distinctive characters that would allow one to discriminate between the species of the leibii group.


2015 ◽  
Vol 52 (1) ◽  
pp. 23-35 ◽  
Author(s):  
Dariusz Kayzer ◽  
Anna Budka ◽  
Klaudia Borowiak ◽  
Janina Zbierska ◽  
Marta Lisiak

SummaryTropospheric ozone affects plant growth and the yield of main pasture species all around the world. Experiments are usually performed in fully controlled conditions; the number of investigations in ambient air conditions is still limited. Moreover, most investigations of the effect of ozone on white clover biomass production consider one series after the other, including a period without leaves. Hence, based on the recommendations, additional series are proposed and studied here. The responses of sensitive and resistant white clover clones are presented and compared using multivariate analysis of variance and profile analysis. The canonical variate analysis used here makes it possible to present the profile comparison of dry matter content of white clover graphically in Euclidean space. The investigations revealed a difference in response between clones and the necessity of using the additional series.


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