Diagnoza
The platform elements of the Protognathodus
apparatus change their omamentation significantly during histogeny by adding some additional
tubercles and making the base more and more robust. Practically all morphologies reported in
literature under different species names within this genus can be identified in the Dzikowiec
collection of Protognathodus. I do not see any discontinuity in the morphologic variability
within particular populations that would allow distinction of more than one species of the genus.
There is also no apparent evolutionary change in platform morphology although the species continues
for a significant time span in the area and those from the upper part of the Dzikowiec section @ig.
8A-C) can be classified in Gnathodus delicatus Branson & Mehl, 1938.
The apparatus of Protognathodus is of a rather generalised polygnathid morphology.
Only the relatively loosely distributed denticles and elongated processes of the oz element may allow
its discrimination from similar apparatuses.B ecause of generalisedm orphology affrnities of the
species are difficult to face.
As there seems to be no need to distinguish more than one species in the assemblage of
Protognathodus from Dzikowiec and apparently also other European localities I attribute it to the
name of the type species. Its type population comes from the GattendorfiaLimestone at Wocklum in
the Rhenish Massif (Bischott 1957) although it remains unclear from which bed. [n the type section
both the Protognathodus fauna and typical assemblageso f the Gattendorfia Stufe are represented.
Luppold et al. (1994'. pl. 4: 1,4, 7, 8) illustrated an almost complete set of ramiform elements of the
Protognathodu,s apparahls from a low-diversity sample of the Stockum Limestone under conventional
form taxonomic names.
It is remarkable that the most primitive species of the gems Gnathodus, G. punctatus (Cooper,
1939) does not show the characteristic feature for later species (and all the idiognathodontids) of its
hi elements: the strong external curvature ofthe ventral process. In this respect the
hi element of G. punctatus resembles rather Protognathodus kockeli. G. delicatus Branson & Mehl,
1938, which in North America occurs in the upper portion of the range of Siphonodella (Thompson
& Fellows 1970), being thus coeval with latest Protognathodus populations in Europe, differs from
P. kockeli only in a more asymmetric distribution of tubercles on the conical part (cup) of the sp
elements. Its apparatus remains unknown but one may suppose that this is a little more advanced
member of the same Protognathodus lineage. Porównanie
Specimens from the topmost Famennian strata at Kowala are difficult to clean from clayish cover and thus are not suitable for SEM photography. They show tuberculation of the basal cone typical of the early Tournaisian populations of Protognathodus. Autekologia Występowanie geograficzne
Kowala (samples Ko-51 and Ko-24) and Dzikowiec (Dz-75). Zasięg czasowy
Terminal Famennian. Materiały muzealne
ZPAL: 42 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. | 
