Breure A.S.H.,Netherlands Center for Biodiversity Naturalis
ZooKeys | Year: 2011
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.
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.
Donovan S.K.,Netherlands Center for Biodiversity Naturalis
Palaios | Year: 2011
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).
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.
Smit H.,Netherlands Center for Biodiversity Naturalis
Zootaxa | Year: 2012
Ten new species and two new subspecies of the water mite genus Arrenurus are described from the Afrotropical region, i.e. Arrenurus abyssinicus n. sp., A. altomontanus n. sp., A. baleensis n. sp., A. bechuanicus n. sp., A. botswanicus n. sp., A. coronopetiolatus n. sp., A. flavus n. sp., A. monocavus n. sp., A. okavango n. sp. and A. serratipetiolatus n. sp., A. chutteri longipes n. subsp., A. concavus longifissus n. subsp. One new species of the genus Thoracophoracarus is de-scribed, T. fluviatilis n. sp. The following taxa are proposed to the rank of a full species: A. chutteri K.O. Viets, A. damasi Lundblad and A. grandis Walter & Bader. Arrenurus odonatophilus Müchberg is transferred to the subgenus Brevicau-daturus Smit, while A. discretus Cook is synonymized with the latter species. Arrenurus vanopus Cook is synonymized with A. capensis Thor, and the female of A. petri Cook must be assigned to A. capensis. The presumed female of A. petri is described therefore again. The male of A. latifoliatus K. Viets is redescribed and the female of this species is described for the first time. Copyright © 2012 Magnolia Press.
Hoso M.,Netherlands Center for Biodiversity Naturalis
Contributions to Zoology | Year: 2012
The nearly neutral theory of molecular evolution predicts that small population size is essential for non-adaptive evolution. Evolution of whole-body left-right reversal in snails is generally a compelling example of non-adaptive speciation, because variants with reversed chirality would suffer from reduced mating opportunities within a population. Despite this reproductive disadvantage, sinistral snail species have repeatedly originated from dextral ancestors in terrestrial pulmonates. Here I show that snail speciation by reversal has been accelerated on oceanic islands. Analysing the global biogeography of 995 genera across 84 stylommatophoran families, I found that the proportion of sinistral snail genera was enhanced in genera endemic to oceanic islands. Oceanic islands are relatively small land masses offering highly fragmented habitats for snails. Thus, the upper limit of population size would probably have been small for a long time there. Oceanic islands may have facilitated the fixation of the nonadaptive allele for speciation by reversal, allowing subsequent ecological divergence of sibling species. This study illustrates the potential role of genetic drift in non-adaptive speciation on oceanic islands.
Hoeksema B.W.,Netherlands Center for Biodiversity Naturalis
Zoosystema | Year: 2012
A total of 35 mushroom coral species (Scleractinia, Fungiidae) was recorded at the southeastern coast of Espiritu Santo, northern Vanuatu, during the SANTO 2006 expedition. One species, Sandalolitha boucheti n. sp., is described as new to science. It can be distinguished from its congeners by dense and thin septa, fine serrated septal dentations, evenly distributed stomata, and a light brown colour. The present species number is distinctly higher than previous records and suggests that northern Vanuatu, Espiritu Santo in particular, should be included in the so-called Coral Triangle, the Indo-West Pacific centre of maximum marine biodiversity, which would require an extension of this area in southeastward direction.
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).
Brazeau M.D.,Netherlands Center for Biodiversity Naturalis
Palaeontology | Year: 2012
The spine-bearing jawed vertebrates (gnathostomes) assigned to the assemblage 'Acanthodii' play a key role in understanding the early evolution of osteichthyans and chondrichthyans. Amongst 'acanthodians', the genus Ptomacanthus has played a prominent role owing to its shark-like tooth files. Recently described braincase material from this taxon contrasts strongly with the osteichthyan-like braincase of Acanthodes, the only other 'acanthodian' for which this anatomy is well known. This seriously challenges acanthodian monophyly or at least the prevailing interpretation of Acanthodes. This study presents a redescription and updated comparison of the anatomy of Ptomacanthus based on unfigured material from the type and referred specimens, as well as adding new data on spine and scale histology. Ptomacanthus is remarkably heterosquamous compared to some other 'acanthodians'. Further to its resemblances to Climatius, Ptomacanthus shares some features of the external morphology of its scales with the enigmatic genus Obtusacanthus. The scale crowns of Ptomacanthus exhibit both superpositional and areal growth. The bases, however, grow separately from the crown. As in Acanthodes, scales are here inferred to be added to the body from posterior to anterior. In spite of its chondrichthyan-like form and characters, Ptomacanthus remains difficult to place on either the chondrichthyan, osteichthyan or gnathostome stem. Different placements each require invoking considerable character incongruence. Nevertheless, these new data from Ptomacanthus provide broader anatomical context for hard tissue characters commonly described on the basis of isolated remains. © The Palaeontological Association.
Zonneveld B.J.M.,Netherlands Center for Biodiversity Naturalis
Plant Biology | Year: 2012
Nuclear DNA content (2C) is reported for all genera of the Cycadales, using flow cytometry with propidium iodide. Nuclear DNA content ranges from 24 to 64pg in cycads. This implies that the largest genome contains roughly 40×10 9 more base pairs than the smallest genome. The narrow range in nuclear DNA content within a genus is remarkable for such an old group. Furthermore, 42 of the 58 plants measured, covering five genera, have 18 chromosomes. They vary from 36.1 to 64.7pg, covering the whole range of genome sizes (excluding the genome of Cycas). Hence, their does not seem to be a correlation between genome size and the number of chromosomes. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.