Lagovidina obliqua Dzik, 2006
Sugerowana cytacja: Dzik J. 2014. Lagovidina obliqua Dzik 2006. Ikonoteka (http://ikonoteka.paleo.pan.pl/xwiki/bin/view/Species/Lagovidina+obliqua+)
Diagnoza M element with triangular outline and straight base, P series with short processes and a high cusp, P1 element with the inner process bifurcating, P2 element strongly bent and twisted, sometimes developing additional anterior process. Porównanie The lineage emerged at Kadzielnia together with Klapperilepis crepida and Tripodellus lobus and continued after the disappearance of these species. This oldest population shows a laterally bent dorsal process of the P2 element without additional branch and a slight angulation at the base of M elements. In a probably slightly younger sample from Miedzianka, still containing K. crepida, the dorsal process of the P2 element is already bifurcated but the cusp is relatively small in most specimens. Probably this is a case of a gradual evolution but the material is not abundant enough to demonstrate this reliably and to substantiate erection of more chronospecies. Moreover, the co-occurrence of L. multidens., with some of its elements somewhat similar to those of early members of Lagovidina, makes their separation not completely sure. Phylogenetic relationship of L. multidens and Ligonodona albidens to the new species is unclear. A puzzling aspect of the apparatus structure of the latter species is that it also contains probable P2 element with a high cusp and inner process which tends to bifurcate. Whether this is a result of parallel evolution or shared inherited character, remains to be clarified. Autekologia Występowanie geograficzne Early form in the K. crepida Zone at Kadzielnia, typical form in the C. quadrantinodosa and the early C. marginifera Zones at Łagów and Miedzianka. Zasięg czasowy Materiały muzealne ZPAL: 625 specimens. Literatura Dzik, J. 2006. The Famennian "Golden Age" of conodonts and ammonoids in the Polish part of the Variscan sea. Palaeontologia Polonica 63, 1-359. |
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