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Albers P.C.H.,Netherlands Center for Biodiversity Naturalis
Geologie en Mijnbouw/Netherlands Journal of Geosciences | Year: 2011

Three nothosaur skulls from the Lower Muschelkalk (Lower Anisian) locality of Winterswijk, the Netherlands, were recently acquired by museum Twentse Welle (Enschede) and have thereby become available for scientific description. Thus, these skulls had been identified as Nothosaurus winterswijkensis, but upon examination these skulls challenge the status of this Nothosaurus species. All diagnostic characters are somehow discredited, but the material can also not be unequivocably be considered as Nothosaurus marchicus, which is the only other obvious candidate. As these fossils originate from the same strata as the type of Nothosaurus winterswijkensis and there is no reason to assume that the animals occupied different ecological niches they are more plausibly considered one species, and Nothosaurus winterswijkensis therefore becomes a junior synonym of Nothosaurus marchicus. The diagnosis of Nothosaurus marchicus is enlarged to include all finds.

The alien razor shell Ensis americanus (Binney) is a common bioclast on Dutch beaches. It is uncommonly encrusted by the balanid Balanus crenatus Brugire on both the interior and exterior surfaces of both valves. This occurs postmortem, but before the ligament breaks. A well-preserved specimen from Zandvoort is described which confirms that this pattern of skeletozoan infestation is initiated in dead shells still in the burrow, but protruding above the sediment surface. After exhumation, the recumbent shell can be further infested by subsequent balanid spatfalls. Such a pattern of encrustation is only likely in burrowing bivalves with a permanent and prominent gape to the shell. © 2011 SEPM (Society for Sedimentary Geology).

Brazeau M.D.,Netherlands Center for Biodiversity Naturalis
Biological Journal of the Linnean Society | Year: 2011

The effects of different coding practices in morphological phylogenetic analysis are well documented. In many cases, we can determine that certain practices can be regarded as undesirable and should be avoided. Certain coding practices do not correctly translate the expected information to the cladistic algorithm. It may go unnoticed that expressions of character information in character lists, which may be entirely logical to any reader, do not necessarily reflect the mathematics employed by a phylogenetic algorithm. Despite a wealth of literature on coding procedures and documentation of these issues, problematic character coding practices are still common. A review is provided of different coding and character formulation practices, particularly relating to multistate character information that may either: (1) lead to a failure to capture grouping information implied in the character list; (2) cause problematic weighting or spuriously high certainty in particular optimizations; and (3) impose congruence artificially, by linking more than one variable character to a particular state. Each of these is reviewed and presented with a hypothetical example. Recommendations for avoiding these pitfalls are described in light of how parsimony algorithms work with character data. Character lists must be drawn up not only to present character variation logically, but also with consideration for how computer algorithms implement cladistic logic. The widespread use of problematic character coding procedures may account for some of the perceived problems with morphological data. Therefore, an exploration of the effects of these methods and standardization of methods should be a goal for the very near future. © 2011 The Linnean Society of London.

The type status is described of 57 taxa from the superfamily Orthalicoidea in the collection of the Brussels museum. Two new species are described: Stenostylus perturbatus sp. n., and Suniellus adriani sp. n. New lectotypes are designated for Bulimulus (Naesiotus) amastroides Ancey, 1887; Bulimulus blanfordianus Ancey, 1903; Bulimulus montivagus chacoensis Ancey, 1897; Bulimus coloratus Nyst, 1845; Plecochilus dalmasi Dautzenberg, 1900; Placostylus porphyrostomus elata Dautzenberg, 1923; Bulimulus ephippium Ancey, 1904; Bulimus fulminans Nyst, 1843; Bulimus funckii Nyst, 1843; Orphnus thompsoni lutea Cousin, 1887; Bulimus melanocheilus Nyst, 1845; Orphnus thompsoni nigricans Cousin, 1887; Orphnus thompsoni olivacea Cousin, 1887; Bulimulus pollonerae Ancey, 1897; Orphnus thompsoni zebra Cousin, 1887. New combinations are: Bostryx borellii (Ancey, 1897); Bostryx carandaitiensis (Preston, 1907); Protoglyptus mazei (Crosse, 1874); Kuschelenia (Vermiculatus) sanborni (Haas, 1947). New synonymies are established for the following nominal taxa: Orphnus thompsoni var. lutea Cousin, 1887 = Kara thompsonii (Pfeiffer, 1845); Orphnus thompsoni var. nigricans Cousin, 1887 = Kara thompsonii (Pfeiffer, 1845); Thaumastus nystianus var. nigricans Cousin, 1887 = Drymaeus (Drymaeus) nystianus (Pfeiffer, 1853); Orphnus thompsoni var. olivacea Cousin, 1887 = Kara thompsonii (Pfeiffer, 1845); Orphnus thompsoni var. zebra Cousin, 1887 = Kara thompsonii (Pfeiffer, 1845). © A.S.H. Breure.

Hoeksema B.W.,Netherlands Center for Biodiversity Naturalis
Marine Biodiversity | Year: 2012

Samples of free-living corals of Favia gravida (Scleractinia: Faviidae) have been studied. They were collected from an intertidal rock pool on Ascension Island, southern Atlantic Ocean. They consist of phaceloid clusters of corallites that appear to be able to easily break apart from each other by the formation of slits inbetween them, which indicates the occurrence of asexual reproduction by fragmentation. The base of the fragments is usually tapering or conical and covered by an epitheca. Small corallites on the base of some specimens suggest that the corals also reproduce by budding. By not depending on a solid substratum for reproduction, the corals appear to be utterly adapted to a free mode of life. These traits have not been reported before from Favia, which normally consists of massive corals. The variable shape of the corals at hand indicate that they have adopted a plastic free-living growth form that appears to be confined to a rock pool habitat. © 2012 The Author(s).

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