Nouvelles observations sur l'anatomie et sur la position systématique d'un poisson téléostéen du Cénomanien du Liban: Pateroperca Woodward

The genus PateropercaWoodward which includes two species, P. libanicaWoodward and P. robusta nov., is described in detail on the basis of acid prepared material from the Cenomanian fish bed of Hadjula (Lebanon). It is demonstrated that Pateroperca does not belong to the Order Ctenothrissiformes contrary to the generally accepted idea. Despite the possession of characters known among Acanthoterygian fishes, it is not possible to show that this genus may be related to the Order Beryciformes and the new family Pateropercidae nov. is left as Ctenosquamata incertae sedis.     

The spermatogenesis of crustaceans. VI. The external morphology of the mature spermatozoa of mytilicola intestinalis,steuer (copepoda)

The external structure of the male gamete of Mytilicola intestinalis is studied under a scanning electron microscope and compared with transmission electron micrographs of thin sections corresponding to the different parts of same. The cell in question is long and filiform, showing, along a significant part of its length, two ridges or expansions helicoidally arranged and diametrically opposed. Four different parts or segments can be identified in this spermatozoon: segment A, characterized by its screw-like aspect; segment B, the longest, provided with well-developed helicoidal expansions; segment C, showing an uneven surface and lacking expansions; and segment D, with a smooth surface and decreasing diameter. The significance of this original structure in a spermatozoon, considered immobile until now, is discussed, stating different hypotheses with regard to the possible mobility of the cell just before fertilization takes place.     

Selecting models to predict the timing of flowering of temperate trees: implications for tree phenology modelling

Classical budburst models (Spring Warming, Sequential, Parallel and Alternating) are unable to fully predict external data, partly because of the methods of optimization used to adjust them. The purpose of this study was to examine different assumptions of budburst models and select those which are best supported by the data, defining new models able to predict external data. Eight models, each differing in one assumption, were fitted and tested using external data. The dataset used to test the models was deduced from aeropalynological data at two stations in France. The results show that some of the models proposed are able to accurately predict external dates of flowering of most of the studied species. The assumptions of those models have been individually tested and shown to improve the models accuracy. Robust estimates of the best predictor models of 12 tree species are presented. The analysis of hypothetical provenance transfer of two species, Buxus sempervirens and Platanus acerifolia, between the two study sites, shows that P. acerifolia estimates are similar in both environments whereas B. sempervirens estimates are variable. This result, which agrees with the genetic characteristics of both species, shows that local adaptation of phenology can also be studied through modelling approaches.     

Taxonomy, biogeography and evolution of Euproctus (Amphibia: Salamandridae), with the resurrection of the genus Calotriton and the description of a new endemic species from the Iberian Peninsula

A phylogeny of West Palearctic Salamandridae based on 1208 bp of mtDNA sequences (300 bp of cytb, 346 bp of 12S rRNA and 562 bp of 16S rRNA) indicates the European brook newts (Euproctus) are polyphyletic. To reflect revised relationships, the Tyrrhenian species (E. montanus ( Savi, 1838 ) and E. platycephalus ( Gravenhorst, 1829 )) are retained in Euproctus Genè, 1839 , while the genus Calotriton Gray, 1858 is resurrected to include the Pyrenean brook newt ( Calotriton asper ( Dugès, 1852 ) comb. nov. ) and a new species from the massif of El Montseny, Catalonia, Spain, described herein as Calotriton arnoldi sp. nov. , which is both morphologically and genetically distinct. Although according to the principle of priority Megapterna Savi, 1838 should take precedence over Euproctus Genè, 1839 , for the sake of nomenclatural stability and in line with Art. 23.9.1 of the International Code of Zoological Nomenclature, Megapterna is considered a nomen oblitum and Euproctus a nomen protectum. The polyphyly of Euproctus (s.l.) contradicts previous, well‐accepted, biogeographical hypotheses and represents a clear case of convergence, involving several morphological traits and a unique reproductive behaviour that is advantageous in stream situations. Molecular dating suggests the Western brook newt lineage (C. asper+C. arnoldi) originated towards the end of the Miocene (8.3 ± 0.11 Mya) and is part of a well‐supported monophyletic assemblage, which also includes Neurergus kaiseri ( Schmidt, 1952 ) and a clade formed by Triturus karelinii ( Strauch, 1870 ), T. carnifex ( Laurenti, 1768 ), T. pygmaeus ( Wolterstoff, 1905 ) and T. marmoratus ( Latreille, 1800 ). Speciation separating E. montanus and E. platycephalus might have coincided with the onset of the Messinian salinity crisis. © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society, 2005, 145 , 555–582.     

Sensory processing in external globus pallidus neurons

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ESTIMATING BODY LENGTH OF PYGMY RIGHT WHALES (CAPEREA MARGINATA) FROM MEASUREMENTS OF THE SKELETON AND BALEEN

Various parts of the skeleton and/or the longest baleen plate of 46 specimens of Caperea marginata from Australia and New Zealand were measured and related to body length. Of the 32 skull, postcranial and baleen-plate measurements available, eight were analysed and seven found to be good predictors of body length, by using a curvilinear model describing their relationship with body length. Greatest skull width, supraoccipital length and mandible length had the smallest prediction limits (± 0.28-0.33 m in small animals, ±0.44-0.58 m in large animals) when compared with postcranial measurements (scapula length, vertebra 7 centrum width). Baleen-plate length was also a useful predictor of body length (±0.32-0.77 m). There was a substantial increase in the arch of the skull as body length increased. Bulla length was not a good predictor of body length, because measurements were highly variable and because the bulla grew little during postnatal life. Physical maturity occurred at body lengths of at least 5.9 m, also the shortest length at which both epiphyses of the humerus and proximal epiphyses of the radius and ulna were fused. Weaning appears to occur at about 3-3.5 m. The following approximate relative age/length classes were erected: dependent calves, <3.6 m; subadults, 3.6-5.5 m; adults, >5.5 m. Females were significantly longer than males in the sample of 22 animals greater than 5.9 m, length of the smallest recorded physically mature animal.     

The Allometry of primate skeletal weight

There is a widely held assumption that skeletal weights of mammals increase disproportionately with increased body size. Recent empirical studies have supported this assumption, and it has been suggested that this might account for the fact that metabolic rate scales to body weight with a negative allometry. Other studies, however, have suggested that skeletal weight in primates is directly proportionate to body weight. The results of this study support this latter interpretation and also indicate that the same is true for two other orders of mammals that were a part of the earlier allometric studies. The evidence suggests that skeletal weight scales isometricallywith body weight within individual mammalian orders. From this it is concluded that skeletal weight does not play any part in determining the negatively allometric scaling of metabolic rate.     

Monoclonal Antibodies Reveal Complex Structure in the Membrane Skeleton of Tetrahymena

ABSTRACT. Twelve monoclonal antibodies were raised that are specific for the membrane skeleton of Tetrahymena . Five were directed against T. pyrifomis and seven were directed against T. thermophila . Some cross-reactivity between species was found. Each monoclonal antibody recognized one of the three major components of epiplasm, i.e. the bands A, B, and C identified in electrophoretic separations of epiplasmic proteins. It was found, using these antibodies, that the epiplasmic proteins A, B, and C have overlapping but independent distributions within the cell.