A new basal ornithopod dinosaur (Frenchman Formation,Saskatchewan, Canada), and implications for late Maastrichtian ornithischian diversity in North America

A small, articulated basal ornithopod skeleton from the Frenchman Formation (late Maastrichtian) of Saskatchewan (RSM P 1225.1), previously referred to the taxon Thescelosaurus, differs from both recognized species of this taxon (Thescelosaurus neglectus and Thescelosaurus garbanii). The differences are taxonomically informative and we recognize this specimen as the holotype of a new species, Thescelosaurus assiniboiensis sp. nov. , diagnosed by the presence of two autapomorphies, and displaying plesiomorphic traits more similar to those of Parksosaurus, than to those of the other Thescelosaurus species. The Frenchman Formation also harbours an intriguing faunal assemblage in which Thescelosaurus represents one of the most abundant dinosaur taxa, and preserves a relatively high proportion of small (putatively juvenile and subadult) specimens of many dinosaur taxa. Further work that increases the faunal sample from this formation, and that permits quantitative comparisons with contemporary formations, will determine whether or not these differences are well supported, and will determine their ultimate palaeobiological significance. Identification of a third species of Thescelosaurus from the late Maastrichtian of North America suggests that this taxon was more diverse than previously recognized, and shows an increase in diversity from the Campanian through the late Maastrichtian, contrasting the trends seen in most other ornithischian clades. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 1157–1198.     

Molecular and morphological evidence for hybridization between endemic Canary Island Convolvulus

Morphological data and molecular data from the chloroplast trn H- psb A region and nuclear ribosomal ITS region are used to test the hypothesis that the problematic Canary Island endemic Convolvulus floridus var. virgatus is a hybrid between the endemic species C. floridus and C. scoparius . Analysis of mean leaf length and width of 58 individuals indicates that accessions referable to C. floridus var. virgatus are intermediate between the parental taxa in leaf dimensions. Direct sequencing of the ITS region of C. scoparius and C. floridus revealed two species-specific ribotypes distinguished by 10 base differences. Examination of ITS chromatograms for putative hybrids revealed polymorphisms at those sites that are diagnostic between species in all except one putative hybrid. Morphological intermediacy and ITS additivity therefore support the hybrid status of C. floridus var. virgatus . An analysis of intraindividual ITS variation confirmed the co-occurrence of both parental ribotypes in putative hybrids and demonstrated that some hybrid individuals contained chimaeric ITS types. It is proposed that chimaeric ITS types are the result of recombination following backcrossing. Sequencing of the trn H- psb A region revealed four haplotypes. Three were, for the most part, confined to C. floridus and putative hybrids although one C. scoparius accession was also found to share this haplotype. The remaining haploype was only found in C. scoparius and putative hybrid accessions. Patterns of haplotype distribution between parental and hybrid accessions suggest multiple, bidirectional hybridization events between C. floridus and C. scoparius . The nomenclature of the hybrid is discussed and the necessary new name C.  ×  despreauxii is proposed.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 187–204.     

Specialized Studies. PRIMATE LOCOMOTION AND MANIPULATION

Book reviewed in this article:
Pan troglodytes (Pongidae). Walking on All Fours. Chimpanzee. By P. LEYHAUSEN
Pan troglodytes (Pongidae). Walking Upright. Chimpanzee. By P. LEYHAUSEN
Homo sapiens (Hominidae). Walking I (boy, aged 11 months). By H. F. R. PRECHTL
Homo sapiens (Hominidae). Walking II (girl, aged 12 months). By H. F. R. PRECHTL
Pan troglodytes (Pongidae). Walking on All Fours II. Chimpanzee. By P. LEYHAUSEN
Gorilla gorilla (Pongidae). Walking on All Fours. Gorilla. By P. LEYHAUSEN
Simia satyrus (Pongidae). Walking on All Fours. Orangutan. By P. LEYHAUSEN
Homo sapiens (Hominidae). Creeping I (boy, aged 10 months). By H. F. R. PRECHTL
Homo sapiens (Hominidae). Creeping II (boy, aged 10 months). By H. F. R. PRECHTL
Homo sapiens (Hominidae). Getting up into a Sitting Position (girl, aged 4 months). By H. F. R. PRECHTL
Homo sapiens (Hominidae). Getting up to a Standing Position (boy, aged 11 months). By H. F. R. PRECHTL