Late Cretaceous-Early Palaeogene Echinoderms and the K/T Boundary in the Southeast Netherlands and Northeast Belgium — Part 5: Asteroids
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pp 379-506 15-01-2007 14:41 Pagina 377 Late Cretaceous-Early Palaeogene echinoderms and the K/T boundary in the southeast Netherlands and northeast Belgium — Part 5: Asteroids John W.M. Jagt Jagt, J.W.M. Late Cretaceous-Early Palaeogene echinoderms and the K/T boundary in the southeast Netherlands and northeast Belgium — Part 5: Asteroids. — Scripta Geol., 121: 377-503, 9 figs., 27 pls, Leiden, December 2000. John W.M. Jagt, Natuurhistorisch Museum Maastricht, Postbus 882, NL-6200 AW Maastricht, The Netherlands, E-mail: [email protected] Key words: Echinodermata, Asteroidea, Late Cretaceous, Early Palaeogene, taxonomy, stratigraphy. All Campanian, Maastrichtian and Danian asteroids known to date from the extended type area of the Maastrichtian Stage, are described and illustrated. The geographic and stratigraphic distribution are documented. Eighteen genera (one of them new) and at least sixty-four species (eight of them new) are listed: Astropecten? sp. nov., astropectinid sp. nov., Coulonia? sp. nov., Lophidiaster? gr. punc- tatus/postornatus, L. pygmaeus Spencer, 1913, Aldebarania sp. nov., Astropectinidae indet., ctenodiscid? indet., benthopectinid sp. 1 (? spp.), benthopectinid sp. 2, Metopaster alexiae sp. nov., M. aff. carinatus Brünnich Nielsen, 1943, M. continuus sp. nov., M. decipiens Spencer, 1913, M. kagstrupensis Brünnich Nielsen, 1943, M. lisannae sp. nov., M. miriamae sp. nov., M. aff. planus (Brünnich Nielsen, 1943), M. praetumidus Schulz & Weitschat, 1975, M. spencerii Brünnich Nielsen, 1943, M. gr. tumidus Spencer, 1913, M. uncatus (Forbes, 1848), M. undulatus Spencer, 1913, M. sp. 1, M. sp. 2, M. sp. 3, M. sp. 4 (aff. elegans Gale, 1987a), Parametopaster? sp., Haccourtaster aemstelensis gen. et sp. nov., Recurvaster antemammillatus sp. nov., R. mammillatus (Gabb, 1876), R. gr. radiatus (Spencer, 1913), R. spiniger sp. nov., Nymphaster alseni (Schulz & Weitschat, 1971), N. spenceri (Rasmussen, 1950), N. studlandensis (Schulz & Weitschat, 1975), N. sp., Chomataster acules Spencer, 1913, Ophryaster? maastrichtensis Umb- grove, 1925, O. magnus Spencer, 1913, O. oligoplax (Sladen, 1891), Comptoniaster peetersorum sp. nov., Crateraster anchylus (Brünnich Nielsen, 1943), C. favosus (Spencer, 1913), C. reticulatus (Schulz & Weitschat, 1981), Caletaster? sp., goniasterid sp. 1, goniasterid sp. 2, goniasterid sp. 3, goniasterid? sp. 4, goniasterid sp. 5, goniasterid sp. 6, goniasterid sp. 7, goniasterid sp. 8, Valettaster gr. ocellatus (Forbes, 1848), Stauranderaster? miliaris Brünnich Nielsen, 1943, S.? sp. (? spp.), Aspidaster? aff. senonen- sis (Valette, 1902), A.? sp. 1, A.? sp. 2 (aff. pistilliferus Forbes, 1848), Pycinaster aff. cornutus Rasmussen, 1945, P. magnificus Spencer, 1913, P.? aff. rosenkrantzi (Brünnich Nielsen, 1943), P. sp. 1, P. sp. 2, and asteriid sp. (? spp.). Quite a number of these must remain in open nomenclature for the time being, being based mainly on limited material. A few of the new taxa will be described elsewhere. Contents Introduction ......................................................................................................................... 377 Material and methods ........................................................................................................ 378 Previous work ..................................................................................................................... 379 Systematic palaeontology .................................................................................................. 383 Acknowledgements ............................................................................................................ 445 References ............................................................................................................................ 445 Introduction What has been stated for crinoids (Jagt, 1999b) and ophiuroids (Kutscher & Jagt, 2000) also goes for asteroid taxa from the Maastrichtian type area. With the exception pp 379-506 15-01-2007 14:41 Pagina 378 378 Jagt. Late Cretaceous and Palaeogene echinoderms, pt 5: Asteroids. Scripta Geol., 121 (2000) of a handful of species these echinoderms have virtually been neglected. In the present paper, at least sixty-four species in eighteen genera are listed and illustrated. Descriptions are brief, except for the new genus and new species, and lists of synonyms generally include only references to papers which provide (more) detailed accounts. Most of the material was collected during the past six to eight years in a number of quarries, both working and disused, and in a few other (natural) outcrops in the area between Aachen, Liège and Maastricht (see Jagt, 1999a for details). Included also are museum collections, although it is realised that these, and those made prior to 1975 in particular, often suffer from a lack of stratigraphic detail. Private collections, notably those of M.J. van Birgelen, M.J.M. Deckers, R.W. Dortangs, L. Indeherberge, and M.M.M. Kuypers have been considered, since these comprise stratigraphically well-documented material. Specimens from these collections illustrated herein have been transferred to the collections of the Natuurhistorisch Museum Maastricht and have the prefix NHMM. The present paper is the fifth in a series of contributions documenting echinoderm faunas of Late Cretaceous and Early Palaeogene age from the extended Maastrichtian type area. For a discussion of the geographic-stratigraphic setting and general refer- ences see Jagt (1999a), and for a brief outline of the project see Jagt (1999b). The pres- ent contribution is taxonomic in nature; a palaeobiological/palaeoecological analysis of these asteroid faunas will be presented in Part 6. The present contribution also comprises a historical account of the research into asteroids, which precedes the systematic descriptions, and includes citations from lit- erature sources not easily accessible. Material and methods Like crinoids and ophiuroids, asteroid skeletons disintegrate rapidly upon death into jumbles of many thousands of small to diminutive ossicles (Blake, 1989, 1996). Most of the asteroid material from the extended Maastrichtian type area comes from the same samples which yielded the crinoids and ophiuroids. Asteroids occur gener- ally as dissociated ossicles only, or skeletal concentrations which may either contain ossicles of the same type, implying that these come from an individual which decom- posed at that particular site, or yield various types of ossicles of more than one species. The latter are considered to represent coprolites (Gale, 1987a; Breton, 1992a); they occur commonly in white chalk facies types. Ossicles are often etched, fragmen- tary, and at times show traces of predation (see Neumann, in press), as well as post- mortem traces such as Asteriastoma cretaceum Breton, 1992a. At a number of localities, rapid burial smothered live populations of benthic organisms. Specimens of astropec- tinid and goniasterid asteroids preserving marginal armature, and with discs relative- ly undisturbed, may be mentioned in this respect. More or less articulated specimens are extremely rare, and may be considered the result of sudden burial (obrution) by storm activity or submarine sediment displacement. Occurrences of such well-pre- served material in the Zeven Wegen and Vijlen members recall specimens from San- tonian-Maastrichtian white chalk strata in southeast England, northern Germany and Denmark. The Nekum and Meerssen members have yielded well-preserved astropec- pp 379-506 15-01-2007 14:41 Pagina 379 Jagt. Late Cretaceous and Palaeogene echinoderms, pt 5: Asteroids. Scripta Geol., 121 (2000) 379 tinids, in part preserved in flint. A new specimen of Nymphaster studlandensis, pre- served in a flint boulder, has recently been found reworked in fluvial deposits at Brunssumerheide. In view of the generally small size of asteroid ossicles, it was decided in many cases to have photomicrographs prepared by Mrs S.M. Kars at the Vrije Universiteit (Amsterdam), using a JEOL JSM-6400 scanning electron microscope. Specimens illus- trated are generally the best preserved and/or most typical in the numerous samples studied, on which the descriptions are based. It should be stressed here that, unlike the crinoid, ophiuroid and echinoid faunas, asteroid diversity cannot be fully assessed at this moment. Of a substantial number of taxa, the available material is simply too limited to allow conclusions about range of variation and ontogenetic changes to be drawn. In addition, the study of fossil aster- oids relies heavily on a direct comparison with extant taxa. To illustrate this: a few small samples were sent to Dr Daniel B. Blake (University of Illinois, Urbana), who informed me (letter of December 1997) that amongst astropectinids some ossicles recall those of Plutonaster Sladen, 1885, while some of the goniasterids resemble those of Pseudarchaster Sladen, 1889, both extant genera. Of particular note, however, is material representing the Pterasteridae, a family almost restricted to deep-water set- tings at the present day. Comparable, if not conspecific, specimens are now known to occur in the upper Lower Maastrichtian of Rügen (M. Kutscher Collection). It is high- ly likely that work under way (Blake & Jagt, in prep.) will yield still new data on the taxonomy and stratigraphic distribution of Late Cretaceous asteroids. Quite a number of forms recorded in the present paper must remain indetermi- nate for now. These include such puzzling specimens as the ones illustrated