Campyloprion Eastman, 1902 is a chondrichthyan having an arched symphyseal tooth whorl similar to that of
Helicoprion Karpinsky, 1899, but less tightly coiled. The holotype of Campyloprion annectans Eastman, 1902,
the type species of Campyloprion, is of unknown provenance, but is presumed to be from the Pennsylvanian
of North America. Campyloprion ivanovi (Karpinsky, 1922) has been described from the Gzhelian of Russia.
A partial symphyseal tooth whorl, designated as Campyloprion cf. C. ivanovi, is reported from the Missourian
Tinajas Member of the Atrasado Formation of Socorro County, New Mexico, USA. Partial tooth whorls from
the Virgilian Finis Shale and Jacksboro Limestone Members of the Graham Formation of northern Texas, USA,
are designated as Campyloprion sp. Two partial tooth whorls from the Gzhelian of Russia that were previously
referred to C. ivanovi are designated as Campyloprion cf. C. annectans. The age of Toxoprion lecontei (Dean,
1898), from Nevada, USA, is corrected from the Carboniferous to the early Permian. An alternative interpretation
of the holotype of T. lecontei is presented, resulting in a reversal of its anterior-to-posterior orientation. The
genera Helicoprion, Campyloprion, and Shaktauites Tchuvashov, 2001 can be distinguished by their different
spiral angles.
Three problems in the taxonomy of Pancratium in Egypt are the lack of publications, a lack of clarity about the relationships between recently distinguished species, and the lack of markers for examining the levels and patterns of variation in rare and endemic species; the latter hinders work in plant conservation genetics. In this study we reassessed the taxonomic status of the Pancratium species of Egypt, and examined morphological and genetic variation within and between species, using specimens from different populations collected throughout its distribution range in the country. Our assessment was based on 38 macromorphological characters mainly representing vegetative parts, flowers, fruits and seeds, in addition to RAPD data. The results revealed five morphologically distinguished Pancratium species in Egypt, of which P. trianthum Herb. is newly recorded. Species identification was confirmed by two phenetic dendrograms generated with 26 quantitative morphological characters and RAPD data, while species delimitation was verified by principal component analysis. The diagnostic floral characters are those of the perianth, corona teeth, pistil, stamens, aerial scape, spathe, and number of flowers. The retrieved RAPD polymorphic bands show better resolution of the morphologically and ecologically closely allied Pancratium species (P. arabicum and P. maritimum), and also confirm the morphological and ecological divergence of P. tortuosum from the other studied species. These results are supported by the constructed UPGMA dendrogram.
Morphometric attributes of 705 stromatoporoid specimens from a number of exposures from the Silurian of Podolia (Ukraine) and the Devonian of the Holy Cross Mountains (Poland), representing a wide array of shallow water carbonate sedimentary environments, have been analysed. Taken into account were such parameters as: general shape of the skeleton, shape of the final growth form (living surface profile), upper surface character, latilaminae arrangement, burial ratio and type of initial surface. A number of new ratios has been introduced, designed mainly to improve the mapping of the outlines of the stromatoporoids upper surfaces. All studied specimens were treated as belonging to one group, and relations between particular attributes were tested. The results were analysed in terms of potential environmental factors influencing stromatoporoid morphometric features. Most of the distinguished attributes are common in the studied group and occur in various combinations, with an important exception of parameters designed to reflect the shape of the skeleton’s upper surface, which are distinctly predominated by convex variants. This indicates that surface concavity was a highly undesired feature among stromatoporoids. Upper surface convexity is interpreted herein as a response to the hazard of clogging of the animals pores by tiny sediment particles suspended in the bottom turbid water layer. Common low burial ratios of final living surface profiles and the occurrence of specimens with a smooth upper surface but a non-enveloping latilaminae arrangement are other reflections of this phenomenon. Burial by sediments and redeposition were also important factors governing stromatoporoid development. No direct arguments indicating photosensitivity of stromatoporoids can be deduced from the presented results. The hitherto postulated allometric tendency among stromatoporoids of starting growth as laminar forms and later adopting consecutively higher profile shapes has not been confirmed here. On the contrary, a tendency for gradual elimination of very high profile forms with increasing stromatoporoid size has been observed. The final shape of a stromatoporoid skeleton was always an effect of a combination of various agents.