Time filter

Source Type

Stefen C.,Senckenberg Naturhistorische Sammlungen Dresden
Vertebrate Zoology

The hair cuticula structure of guard hairs of Laonastes aenigmamus is briefl y described. On average the hairs are 17.13 mm long and 42.63 μm wide below the shield. The cuticle scales show smooth free edges and are crenate only at the tip of the hairs. Some parameters including height, width and area of scale are measured. Source

Vegliante F.,Senckenberg Naturhistorische Sammlungen Dresden | Hasenfuss I.,Friedrich - Alexander - University, Erlangen - Nuremberg
Annual Review of Entomology

The morphology of 21 exocrine glands and 13 supposedly exocrine structures recorded for lepidopteran larvae is reviewed. The epitracheal glands, for which a double role (exocrine and endocrine) has been demonstrated, are examined as well. Function is well known for at least 8 glands but completely unknown for 6 glands, for 10 putative glandular structures, and for the exocrine component of the epitracheal glands. Functional studies on the remaining structures are insufficient; in some cases (mandibular gland and adenosma) homologous glands may play a different role depending on the species, and only a few taxa have been examined. The secretions of 13 glandular types have been analyzed chemically. The histology of 11 glands is known at the ultrastructural level, whereas that of 6 glands and 7 putative glandular structures is completely unknown. Comparative anatomical studies of the osmeterium, adenosma, and Verson's glands may yield useful information for phylogenetic reconstructions. © 2012 by Annual Reviews. All rights reserved. Source

Stefen C.,Senckenberg Naturhistorische Sammlungen Dresden
Palaeontologia Electronica

A morphologic and morphometric study of teeth of some beavers of the group of Palaeocastorinae is presented in order to demonstrate that statistic analyses of tooth parameters could contribute to a better understanding of this group of beavers. The focus was laid on larger samples of Capacikala gradatus, Palaeocastor nebrascensis and "Capatanka" cankpeopi. Additionally, some cranial measurements are briefly considered. Overall morphology of the teeth is very similar in the three genera and can hardly be used to differentiate the considered taxa. Except for hypo- and mesostriae, striae in general are rare in the available material. Whether their rarity is due to how few unworn or little worn teeth are available, or due to the lack of these structures is unclear. Striae thus cannot be considered of taxonomic value in this group. Likewiese, neither the presence of anterior or posterior fossettes, nor their shape and orientation are taxonomically diagnostic. The discriminant analysis of wear-independent residuals showed some separation of Capacikala gradatus,"Capatanka" cankpeopi and Palaeocastor nebrascensis with reasonable sized samples, but not all statistically significantly. The separation of all studied taxa on the basis of the wear-independent residuals of teeth showed some power to separate groups, but here the influence of the differences in sample seizes might be too strong to make clear statements. Also the comparison of tooth row length did not give a clear size separation between all taxa. Size data on skulls are limited and may not represent the real variation. The data of tooth morphometry indicate similarities between C. cankpeopi and C. magnus thus their taxonomic status should be reviewed. Also the differentiation between Capacikala parvus, Capacikala gradatus and Capatanka minor should be reviewed as well as the species assignments in Palaeocastor. Material assigned to Palaeocastor sp. could be separated into three size forms. P. fossor is clearly separated. © Society for Vertebrate Paleontology March 2010. Source

Hemigrammus fi lamentosus spec. nov. from the rio Araguaya basin is described. There are a typical and a pathological form of the species. The species is closely related with H. taphorni Benine & Lopez, 2007. Typically are (1) the sexualdimorphism and sexualdichromatism, (2) the development of a humeral spot (no humeral spot in H. filamentosus spec. nov. vs. a humeral spot in H. taphorni), (3) the development of a caudal spot (a longitudinal band in the caudal region of the body and no caudal spot in H. filamentosus spec. nov. vs. a caudal spot in H. taphorni), (4) the number of lateral scales (32 to 35 in H. filamentosus spec. nov. vs. 30 to 32 in H. taphorni). Source

The type specimens of the Characiformes (Teleostei: Ostariophysi) of the Museum of Natural History of Berlin are listed, investigated and the current status discussed. Each taxon is fi gured with its historical original picture, a lateral view and an xray foto. Herein, first the African taxa (families Hepsetidae, Alestidae, Citharinidae and Distichodontidae) are described after a short historical overview about the development of the collection. There are type specimens of 23 taxa of Characiformes from Africa (represented by 6 holo-, 12 syn- And 4 paralectotypes). 17 taxa are valid and 6 are synonyms of other species. In a second part of this publication the type specimens of South-American Characiformes (other than Characidae) and in a third part the Characidae sensu stricto will be studied and discussed. Source

Discover hidden collaborations