The present record from the white chalk of Holtug (Stevns Klint, Sjaelland) of the smali, distinctive phymosomatid echinoid Gauthieria altema (Kutscher, 1985) constitutes a notable addition to the latest Maastrichtian echinoid faunas in Denmark. Although both specimens available are crushed, preservation on the whole is better than the type material from the upper Lower Maastrichtian of Rugen (northeast Germany), and enables a more detailed description of the species, which was originally placed in Hemithylus Arnaud, 1896 but which is here transferred to the genus Gauthieria Lambert, 1888. One of the specimens preserves a single demipyramid and epiphysis of the lantern.
Hanken, N.‐M., Uchman, A. & Jakobsen, S. L. 2012 (January): Late Pleistocene–early Holocene polychaete borings in NE Spitsbergen and their palaeoecological and climatic implications: an example from the Basissletta area. Boreas , Vol. 41, pp. 42–55. 10.1111/j.1502‐3885.2011.00223.x. ISSN 0300‐9483 Limestone and dolomite bedrock surfaces, together with blocks derived from these underlying bedrocks, at Basissletta, NE Spitsbergen, contain Late Pleistocene–early Holocene, shallow‐marine, spionid polychaete borings Caulostrepsis taeniola Clarke, Caulostrepsis contorta Bromley & D'Alessandro, and Maeandropolydora isp. The borings occur about 9–78 m above present sea level, and this is the northernmost known occurrence of these trace fossils. 14 C dating of wood, whalebone and bivalves in the vicinity and in neighbouring areas indicates that the borings have a radiocarbon age spanning from about 7 to 11 ka. Recent borings of these ichnotaxa have not been found in the sea around Spitsbergen. The presence of the fossil borings indicates that invasion of boring polychaetes to the northern part of the Barents Sea region was limited to a Late Pleistocene–early Holocene temperature optimum. The presence of Caulostrepsis and Maeandropolydora on subaerially exposed shallow‐water Pleistocene–Holocene bedrock surfaces in arctic areas can be a valuable tool with which to evaluate both postglacial emergence and climatic oscillations because they indicate a summer surface water temperature of at least 8 °C.
Application of new preparation techniques for cleaning and study of fossil crabs to Dromiopsis rugosa (Schlotheim, 1820), from the late middle Danian limestone in the Fakse quarry, Denmark, has revealed remarkable detail of the carapace surface and epibionts infesting inner and outer surfaces of the carapace. Epibionts, identified as clionid sponges, scleractinian corals, cheilostome and ctenostome bryozoans, serpulid worms, and brachiopods, are interpreted as having attached to molted carapaces after the molted carapace had been released.
Epibionts on both living and fossil decapod crustaceans may serve as valuable proxies for paleoecological factors such as behavior and environment. Prevalence of epibionts, as observed primarily on the carapaces of fossil brachyurous decapod crustaceans, appears to be less than observed on living crabs, based upon observations in the literature, and from the study of a limited preserved biological and fossil collection. Among these factors, the three most important are that many extant epibionts do not possess skeletal structures and, therefore, are unlikely to be preserved; the epicuticle upon which epibionts attach to living brachyurans is lightly calcified and tends to be lost readily as a result of taphonomic processes; and the most common mode of preservation of fossil brachyurans is in concretions which tend to break open and leave a layer of cuticle on the counterpart, thus obscuring the potential surface of attachment of epibionts. Other factors such as the life habits of the crab, whether burrowing, burying, or remaining above the substrate; lifestyle, whether benthic or pelagic; and duration of the intermolt phase of the organism also play important roles in potential prevalence of epibionts. Careful preparation of part and counterpart remains of brachyurans as well as reference to the occurrence of epibionts in systematic studies will enhance knowledge of the host and epibiont.
New taxa of thoracican cirripedes are recorded from the Eocene Mo Clay of northwest Jutland, Denmark, namely Stipilepas molerensis Carriol n. gen., n. sp., a scalpelliform gooseneck barnacle, and Plesiobrachylepas jutlandica Carriol n. gen., n. sp., a brachylepadomorph sessile form. This material is of importance in that the former not only represents the first extinct example of the tribe Ashinkailepadini, it also is the second fossil neolepadine, while the latter adds to the diversity of the family Brachylepadidae, which previously embraced only three genera. The geological context of these taxa is outlined and their phylogenetic interest discussed.
The present record from the white chalk of Holtug (Stevns Klint, Sjælland) of the small, distinctive phymosomatid echinoid Gauthieria alterna (Kutscher, 1985) constitutes a notable addition to the latest Maastrichtian echinoid faunas in Denmark. Although both specimens available are crushed, preservation on the whole is better than the type material from the upper Lower Maastrichtian of Rügen (northeast Germany), and enables a more detailed description of the species, which was originally placed in Hemithylus Arnaud, 1896 but which is here transferred to the genusGauthieria Lambert, 1888. One of the specimens preserves a single demipyramid and epiphysis of the lantern.
