Palmatolepis schindewolfi Müller, 1956 from the P. trachytera Zone at Kowala and the P. jugosus Zone at Ostrówka in the Holy Cross Mountains.

Diagnoza

Variable shape of P₁ elements with mature elements showing frequently very narrow and sharp lobes of the platform, while juveniles may lack any posterior processes having instead a large rounded anterior lobe.

Porównanie

P. schindewolfi is a variable species. Even the very large sample Ost-12, with almost eight hundred P₁ elements has not helped much in identification of possible cryptic species within the observed range of variability. The anterior lobe is semicircular in outline and gently convex in the dominant morphotype (usually classified as P. maxima, e.g., Metzger 1994), whereas the posterior lobe is well developed and sharply pointed. The variability extends in three main directions. One of the extreme morphotypes develops a crenulated marginal ridge of the anterior lobe. It is transitional to P. trachytera but just a couple of such specimens (P. perlobata sigmoidea Ziegler, 1962) have been found and the demarcation of P. schindewolfi and P. trachytera seems rather objective. A possibility remains, however, that some cross-breeding between them took place. The second extreme morphotype lacks the posterior lobe and the whole platform is triangular in outline (Palmatolepis perlobata helmsi Ziegler, 1962). There is a complete gradation connecting it with the modal morphology of the population. No morphologic gap or even a lowering of frequency that would substantiate species distinction has been observed. The third extreme morphotype is the most troublesome. These are also specimens with reduced posterior lobe but the platform margins are roughly parallel and the whole robust element is strongly twisted (P.perlobata postera Ziegler, 1960). Their most striking feature is the anterior lobe with its ventral end protruding far from the blade. There is also a complete gradation between this morphology and the modal one but the transitional specimens may not be numerous enough to give a normal distribution of morphologic classes. As the evidence is equivocal, no separate taxon is here recognized.

The P₂ elements are equally variable. They are always highly arched with a dominant cusp. The platform may form a wide asymmetric leaf-like shelf but may be almost lacking in other morphotypes, with robust appearence of denticulation. There is no clear correspondence between these morphologies and size so they probably correspond to ranges of variability in platform extent and robustness in P₁ elements.The external process tends to be bifurcated in late populations.

Elements of the symmetry transition series are very irregular in appearance and variable, which obscures distinctions between locations. Their denticulation is rather robust, with somewhat irregularly sinuous distribution and no dominant cusp. Those virtually symmetrical with subquadrate apical part and arched processes, apparently represent S₀ elements. Similar in shape but somewhat asymmetrical elements with additional process of variable length represent the S₁ location. The process may be incipient and rarely the additional second process developed, which suggests that this morphology overlaps with the neighboring S₀ and S₂ locations. Similarly arched elements without processes are probably typical for the S₂ location.

S_3-4 elements are strongly asymmetric, with one process almost straight or gently curved, the other sinuous and they diverge at the apex at a narrow angle.

M elements differ from those of Conditolepis in the presence of a dominant cusp, weak dorsal denticles and somewhat angular disposition of processes as seen in profile.

Autekologia

Występowanie geograficzne

Łagów, Ostrówka, Kowala, and Miedzianka.

Zasięg czasowy

P. trachytera to P. jugosus Zones. 

Materiały muzealne

ZPAL: 6,378 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.