Vanmanenia maculata, new species, is described from the middle and lower Chang-Jiang basin in Hubei, Hunan, and Jiangxi provinces, South China. This new species, along with V. caldwelli, V. stenosoma, and V. striata, is distinguished from all other Chinese species of the genus by lacking secondary rostral barbels. It is distinct from V. caldwelli and V. striata in anus placement, rostral lobule...

A new species of nemacheilid loach, Triplophysa longliensis, is described from Yudonghe River, a small tributary of Pearl River in Guizhou Province, China. It can be distinguished from other valid Triplophysa loaches by the following combination of characters: body smooth and scaleless; head tapering; lips thin and smooth; posterior chamber of gas bladder highly developed, long, bag-shaped, tip...

The molecular status of nine species of the genus Alburnoides from different river drainages in Iran and additionally by seven species from Europe was assessed. mtDNA COI gene sequences from freshly collected specimens and available NCBI data revealed four major phylogenetic lineages. Based on the results, a distinct taxon from the Cheshmeh Ali (Ali Spring), a Damghan River tributary in the end...

Sonic hedgehog is involved in vertebrate tissue interactions during development. During early feather development, Sonic hedgehog appears very early in epithelial placodes. During late feather development, Sonic hedgehog expression precedes the development of the marginal plates and is specifically localized in the marginal plate epithelium, which will later undergo cell death. By using retrovi...

The actinopterygian fish †Hemicalypterus weiri Schaeffer, 1967 is herein redescribed and rediagnosed based on new information collected from reexamination of museum specimens as well as examination of recently collected specimens from the Upper Triassic Chinle Formation of San Juan County, Utah, United States. †Hemicalypterus is distinguishable by its deep, disc-shaped compressed body; ganoid-s...

The chick dermis is known to control the formation of feathers and interfeathery skin in a hexagonal pattern. The evidence that the segregation of two types of fibroblasts involves Delta/Notch signalling is based on three facts. Rings of C-Delta-1-expressing fibroblasts precede and delimit the forming feather primordia. C-Delta-1 is uniformly expressed in the dermis of the scaleless mutant, whi...

Consider a nearly regular point pattern in which a Delaunay triangulation is comprised of nearly equilateral triangles of the same size. We propose to model this set of points with Gaussian perturbations about a regular mean configuration. By investigating triangle subsets in detail we obtain various distributions of statistics based on size, or squared size of the triangles which is closely re...