Lagovidina obliqua sp. n. from the late K. triangularis Zone at Jabłonna (sample J-53a), the K.crepida Zone at Kadzielnia (sample KA-7, KA-6, KA3) and Miedzianka (sample Md-1), and the C. quadrantinodosa Zone at Łagów (sample Ł-28); specimens ZPAL cXVI/1907, 1663, 1664,1660, 1661,1723, 1906, 1665, 1662, 1905, 1666, 1667, 1669, 1668, 1671, 1670, 1673, 1674 and 1672.

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.