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Campylopus Brid. is a widely distributed genus with some very generalist species. Morphological differences between non and sex-expressing plants and the frequent occurrence of non-sex-expressing shoots have generated difficulties in the identification of the group. Our main objective was to morphologically compare the gametophytes of two species of Campylopus: Campylopus julaceus A.Jaeger and Campylopus lamellatus Mont. We performed morphometric analyses (based on 21 gametophyte characters), quantified their sexual expressions, and tested the viability of the asexual propagula produced by C. julaceus. Our results indicate that those putative species do not form two mutually exclusive groups. Sexual expression in C. julaceus was significant (84.4%, with 88.2% females and 11.8% males), compared to the low expression of C. lamellatus (5.29%, 55.5% females and 44.5% males). Asexual propagula occurred in both species, but were more frequently expressed in C. julaceus (100% of the samples; C. lamellatus 31%). Those propagula showed 50 to 60% regeneration, forming rhizoids or green protonemata within only two days. Campylopus lamellatus is often encountered sterile, while C. julaceus is apparently only a sexual form. Additionally, as the sexual success of the species can be restricted by the spatial separation of the sexes, asexual propagula should be useful for population maintenance. Finally, we highlight the importance of studies focusing on DNA analyses at the population level and involving specimens collected globally to better understand the delimitation of sympatric species of Campylopus. [ABSTRACT FROM AUTHOR]

Abstract: The evolution of the coccolith genus Lotharingius was investigated in 18samples from the West Rodiles section (Asturias, Northern Spain), Upper Pliensbachian-Lower Toarcian in age. In each sample, the length and width of the coccolith and of its central area were measured on 150specimens of Lotharingius. A total of 2700specimens were measured, and 10,800measurements were obtained. Based on the results of the morphometric analysis, the stratigraphic ranges, the abundance patterns and the light microscope observations, the aims of this work are to determine whether the specimens analysed correspond to different species, to distinct ecophenotypes or to an anagenetic lineage of morphotypes of a single species with overlapping stratigraphic ranges, and to test the influence of the paleoenvironmental perturbations during the Early Toarcian on the studied genus. Three species of Lotharingius were distinguished: L. hauffii, L. sigillatus and L. crucicentralis. Based on central area size and structure, two morphotypes (A and B) of L. hauffii were differentiated. All the parameters measured show a great overlap between the morphotypes and species. An increase in both coccolith and central area size and a development of more complex central area structures were observed through the studied section. L. hauffii is the smallest form, followed by L. sigillatus, and finally L. crucicentralis is the largest species and has the most complex central area structure. A clear decrease in size or “dwarfing” of the species was observed in the samples corresponding to the Early Toarcian environmental perturbations. L. crucicentralis was not identified in these samples. We hypothesize that the changes in size and abundance of the Lotharingius species could be related to the unfavourable palaeoenvironmental conditions for the biomineralization of their coccoliths. [Copyright &y& Elsevier]