Dataset Information

Systematics and molecular phylogeny of the family oscarellidae (homoscleromorpha) with description of two new oscarella species.

ABSTRACT: The family Oscarellidae is one of the two families in the class Homoscleromorpha (phylum Porifera) and is characterized by the absence of a skeleton and the presence of a specific mitochondrial gene, tatC. This family currently encompasses sponges in two genera: Oscarella with 17 described species and Pseudocorticium with one described species. Although sponges in this group are relatively well-studied, phylogenetic relationships among members of Oscarellidae and the validity of genus Pseudocorticium remain open questions. Here we present a phylogenetic analysis of Oscarellidae using four markers (18S rDNA, 28S rDNA, atp6, tatC), and argue that it should become a mono-generic family, with Pseudocorticium being synonymized with Oscarella, and with the transfer of Pseudocorticium jarrei to Oscarella jarrei. We show that the genus Oscarella can be subdivided into four clades, each of which is supported by either a small number of morphological characters or by molecular synapomorphies. In addition, we describe two new species of Oscarella from Norwegian fjords: O. bergenensis sp. nov. and O. nicolae sp. nov., and we compare their morphology, anatomy, and cytology with other species in this genus. Internal anatomical characters are similar in both species, but details of external morphology and particularly of cytological characters provide diagnostic features. Our study also confirms that O. lobularis and O. tuberculata are two distinct polychromic sibling species. This study highlights the difficulties of species identification in skeleton-less sponges and, more generally, in groups where morphological characters are scarce. Adopting a multi-marker approach is thus highly suitable for these groups.

SUBMITTER: Gazave E

PROVIDER: S-EPMC3667853 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Systematics and molecular phylogeny of the family oscarellidae (homoscleromorpha) with description of two new oscarella species.

Gazave Eve E Lavrov Dennis V DV Cabrol Jory J Renard Emmanuelle E Rocher Caroline C Vacelet Jean J Adamska Maja M Borchiellini Carole C Ereskovsky Alexander V AV

PloS one 20130530 5

The family Oscarellidae is one of the two families in the class Homoscleromorpha (phylum Porifera) and is characterized by the absence of a skeleton and the presence of a specific mitochondrial gene, tatC. This family currently encompasses sponges in two genera: Oscarella with 17 described species and Pseudocorticium with one described species. Although sponges in this group are relatively well-studied, phylogenetic relationships among members of Oscarellidae and the validity of genus Pseudocort ...[more]

PMID: 23737959

Similar Datasets

Project description:Sponges are known to possess remarkable reconstitutive and regenerative abilities ranging from common wounding or body part regeneration to more impressive re-building of a functional body from dissociated cells. Among the four sponge classes, Homoscleromorpha is notably the only sponge group to possess morphologically distinct basement membrane and specialized cell-junctions, and is therefore considered to possess true epithelia. The consequence of this peculiar organization is the predominance of epithelial morphogenesis during ontogenesis of these sponges. In this work we reveal the underlying cellular mechanisms used during morphogenesis accompanying ectosome regeneration in the homoscleromorph sponge model: Oscarella lobularis. We identified three main sources of novel exopinacoderm during the processes of its regeneration and the restoration of functional peripheral parts of the aquiferous system in O. lobularis: (1) intact exopinacoderm surrounding the wound surface, (2) the endopinacoderm from peripheral exhalant and inhalant canals, and (3) the intact choanoderm found on the wound surface. The basic morphogenetic processes during regeneration are the spreading and fusion of epithelial sheets that merge into one continuous epithelium. Transdifferentiation of choanocytes into exopinacocytes is also present. Epithelial-mesenchymal transition is absent during regeneration. Moreover, we cannot reveal any other morphologically distinct pluripotent cells. In Oscarella, neither blastema formation nor local dedifferentiation and proliferation have been detected, which is probably due to the high morphogenetic plasticity of the tissue. Regeneration in O. lobularis goes through cell transdifferentiation and through the processes, when lost body parts are replaced by the remodeling of the remaining tissue. Morphogenesis during ectosome regeneration in O. lobularis is correlated with its true epithelial organization. Knowledge of the morphological basis of morphogenesis during Oscarella regeneration could have important implications for our understanding of the diversity and evolution of regeneration mechanisms in metazoans, and is a strong basis for future investigations with molecular-biological approaches.

Project description:BackgroundThe Gesneriaceae genus Chiritopsis, confined almost exclusively to cave or cave-like microhabitats of limestone karsts of southern China, was described to distinguish it from Chirita by much smaller flowers and generally miniature plant sizes in the former genus. However, molecular phylogenetic analyses showed that Chiritopsis is polyphyletic and its species delimitation has been problematic. To understand how many times Chiritopsis-like species have evolved from within the recircumscribed Primulina and to further clarify their species identification, we sampled all but two recently described species of Chiritopsis-like Primulina and reconstructed their phylogenetic relationship based on DNA sequences of nuclear ITS and chloroplast trnL-F and trnH-psbA.ResultsWith 182 accessions of 165 taxa of Primulina sampled, our analyses placed the 40 accessions of 25 taxa of Chiritopsis-like Primulina in 17 unrelated positions, indicating at least 17 independent origins of the traits associated with caves or cave-like microhabitats. Of the 17 clades containing Chiritopsis-like Primulina, Clade 1 is composed of P. bipinnatifida, P. cangwuensis, P. jianghuaensis, P. lingchuanensis, and P. zhoui, as well as additional samples that show variable and overlapping morphology in leaf shapes. Clade 10 includes P. cordifolia, P. huangii, and P. repanda, while Primulina repanda var. guilinensis is not placed within Clade 10. Primulina glandulosa var. yangshuoensis is not placed in the same clade of P. glandulosa.ConclusionsBased on our data, P. cangwuensis, P. jianghuaensis, and P. lingchuanensis are proposed to synonymize under P. bipinnatifida, with P. zhoui treated as a variety of P. bipinnatifida. Primulina repanda var. guilinensis is transferred as P. subulata var. guilinensis comb. nov. and Primulina pseudoglandulosa nom. nov. is proposed for P. glandulosa var. yangshuoensis. One new species is named P. chingipengii to honor the late Dr. Ching-I Peng (1950-2018).

Dataset Information

Systematics and molecular phylogeny of the family oscarellidae (homoscleromorpha) with description of two new oscarella species.

Publications

Systematics and molecular phylogeny of the family oscarellidae (homoscleromorpha) with description of two new oscarella species.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets