Toward a resolution of the cosmopolitan Botryllus schlosseri species complex (Ascidiacea, Styelidae): mitogenomics and morphology of clade E (Botryllus gaiae)

Author(s):  
Riccardo Brunetti ◽  
Francesca Griggio ◽  
Francesco Mastrototaro ◽  
Fabio Gasparini ◽  
Carmela Gissi

Abstract Botryllus schlosseri is a model colonial ascidian and a marine invader. It is currently recognized as a species complex comprising five genetically divergent clades, with clade A globally distributed and clade E found only in Europe. This taxon has also been recently redescribed by designation of a clade A specimen as the neotype. To clarify the taxonomic status of clade E and its relationship to clade A, we examine the entire mitochondrial genome and study the morphology of clade E. The mitogenome of clade E has an identical gene order to clade A, but substantially differs in the size of several non-coding regions. Remarkably, the nucleotide divergence of clade A-clade E is incompatible with the intraspecies ascidian divergence, but similar to the congeneric one and almost identical to the divergence between species once considered morphologically indistinguishable (e.g. the pair Ciona intestinalis (Linnaeus, 1767)-Ciona robusta Hoshino & Tokioka, 1967, and the pair Botrylloides niger Herdman, 1886-Botrylloides leachii (Savigny, 1816)). Clade E differs morphologically from the Botryllusschlosseri neotype mainly in the number and appearance of the stomach folds, and the shape of the anal opening, the first intestinal loop and the typhlosole. Our integrative taxonomical approach clearly distinguishes clade E as a species separate from Botryllusschlosseri, with unique morphological and molecular characters. Therefore, we here describe clade E as the new species Botryllus gaiae sp. nov.

PLoS ONE ◽  
2017 ◽  
Vol 12 (1) ◽  
pp. e0169944 ◽  
Author(s):  
Marie L. Nydam ◽  
Kirsten B. Giesbrecht ◽  
Emily E. Stephenson

2021 ◽  
Author(s):  
Drew R. Schield ◽  
Elizabeth S.C. Scordato ◽  
Chris C.R. Smith ◽  
Javan K. Carter ◽  
Sidi Imad Cherkaoui ◽  
...  

2017 ◽  
Vol 69 ◽  
pp. 60-74 ◽  
Author(s):  
Marie L. Nydam ◽  
Emily E. Stephenson ◽  
Claire E. Waldman ◽  
Anthony W. De Tomaso

2021 ◽  
Vol 744 ◽  
Author(s):  
Neil Cumberlidge ◽  
Emily Johnson ◽  
Paul F. Clark ◽  
Martin J. Genner

The taxonomic status of the widely distributed freshwater crab Potamonautes lirrangensis (Rathbun, 1904) sensu lato is revised because morphological and molecular evidence indicates that this taxon is a complex comprising more than one species. Four taxa are now recognized: Potamonautes lirrangensis (Rathbun, 1904) s. str. and P. kisangani sp. nov. from the Middle Congo River in Central Africa, P. amosae sp. nov. from the drainages of Lakes Kivu and Tanganyika, and P. orbitospinus (Cunnington, 1907) from Lake Malawi which had been previously synonymised with P. lirrangensis s. lat. Diagnoses, illustrations and distribution maps are provided for each of these taxa and they are compared to similar species from Central and Southern Africa.


Zootaxa ◽  
2018 ◽  
Vol 4403 (2) ◽  
pp. 307 ◽  
Author(s):  
OLIVIER S. G. PAUWELS ◽  
ROMAN A. NAZAROV ◽  
VLADIMIR V. BOBROV ◽  
NIKOLAY A. POYARKOV

Based on genetic, morphological and chromatical comparisons we evaluate the taxonomic status of two southern Vietnamese forest-dwelling populations of the Cyrtodactylus irregularis species complex. We confirm the allocation of the population from Binh Chau—Phuoc Buu Nature Reserve (Ba Ria—Vung Tau Province) to C. cattienensis and we describe the population of Nui Chua National Park (Ninh Thuan Province) as Cyrtodactylus sangi sp. nov. This brings to 18 the number of species within the C. irregularis complex and to 41 the number of described Cyrtodactylus species recorded from Vietnam. 


2021 ◽  
Vol 106 ◽  
pp. 325-339
Author(s):  
Shirley A. Graham ◽  
Peter W. Inglis ◽  
Taciana B. Cavalcanti

Crenea Aubl. (Lythraceae) is a ditypic genus of subshrubs occurring in mangrove vegetation on the coasts of northern South America. Phylogenetic analyses based on morphology have offered unresolved and conflicting phylogenetic positions for the genus in the family. This study presents the first molecular sequences for Crenea, from nrITS, rbcL, trnL, trnL-F, and matK regions. Molecular phylogenetic analyses find full support for Crenea within Ammannia L., a relationship not previously recognized. Ammannia is a globally distributed genus of terrestrial to amphibious herbs mostly occurring in freshwater marshes and wetlands. It was recently reconfigured based on phylogenetic evidence to include the genera Nesaea Comm. ex Kunth and Hionanthera A. Fern. & Diniz. The transfer of Crenea to Ammannia further extends the morphological, ecological, and biogeographical diversity of Ammannia and provides the final evidence defining Ammannia as a monophyletic lineage of the Lythraceae. A revised circumscription of Ammannia s.l. adds several new morphological character states and the first species in the genus restricted to mangrove vegetation. Two changes in taxonomic status are made: Ammannia maritima (Aubl.) S. A. Graham, P. W. Inglis, & T. B. Cavalc., comb. nov., and Ammannia patentinervius (Koehne) S. A. Graham, P. W. Inglis, & T. B. Cavalc., comb. nov. The new combinations are described, a list of exsiccatae examined is provided, and the effects of the reconfiguration to the morphology and biogeography of the genus are detailed.


Zootaxa ◽  
2012 ◽  
Vol 3277 (1) ◽  
pp. 43 ◽  
Author(s):  
STEVEN L. POWERS ◽  
BERNARD R. KUHAJDA ◽  
SARAH E. AHLBRAND

We examined geographic variation within the Ashy Darter, Etheostoma cinereum, of the mitochondrially enconded cyto-chrome b gene (cyt b) and nuclear recombination activation gene 1 (RAG1) as well as pigmentation, 6 meristic variables,and 20 morphometric variables for patterns indicative of speciation within the complex. Four geographically disjunct en-tities were identified by at least one of the datasets corresponding to the Cumberland, Duck, Elk, and upper Tennesseeriver systems. Monophyly of cyt b and RAG1 sequences, modal meristic differences, moderate morphometric divergence,and unique pigmentation in specimens from the Cumberland River suggest this entity represents an evolutionary speciesunder many different species concepts and is described herein as Etheostoma maydeni. Other populations exhibit varyingdegrees of divergence in the different datasets and have conflicting relationships in phylogenetic analyses using cyt b andRAG1 sequences, leaving the evolutionary history and taxonomic status of the Duck, Elk and upper Tennessee populations unclear.


2018 ◽  
Vol 16 (4) ◽  
Author(s):  
Leandro Marajó ◽  
Patrik F. Viana ◽  
Milena Ferreira ◽  
Lúcia H. Rapp Py-Daniel ◽  
Eliana Feldberg

ABSTRACT Farlowella is one of the most diverse genera of the Loricariinae, restricted to South America rivers. The taxonomic and phylogenetic relationships among its species are contentious and, while genetic studies would contribute to the understanding of their relationships, the only available datum refer to the karyotype description of only one species. In the present study two Amazonian species, Farlowella cf. amazonum and F. schreitmuelleri, were analyzed using conventional and molecular cytogenetic procedures. Both species had diploid chromosome number 58, but different fundamental numbers (NF) 116 and 112, respectively, indicative of chromosomal rearrangements. C-banding is almost poor, especially in F. cf. amazonum, and occurs predominantly in the centromeric and in some telomeric regions, although genome of F. schreitmuelleri possessed a much larger heterochromatin amount then those of F. cf. amazonum. The chromosomes bearing the NOR sites were likely the same for both species, corresponding to the 1st metacentric pair in F. cf. amazonum and to the 28th acrocentric in F. schreitmuelleri. The location of the 5S rDNA was species-specific marker. This study expanded the available cytogenetic data for Farlowella species and pointed the remarkable karyotype diversity among species/populations, indicating a possible species complex within genus.


Zootaxa ◽  
2011 ◽  
Vol 2876 (1) ◽  
pp. 1 ◽  
Author(s):  
AURÉLIEN MIRALLES ◽  
JÖRN KÖHLER ◽  
FRANK GLAW ◽  
MIGUEL VENCES

The present paper constitutes a study on a taxonomically confusing group of closely related species belonging to the Malagasy skink genus Madascincus, currently encompassing the nominal species M. polleni, M. intermedius and M. stumpffi. Based on combined analyses of mitochondrial and nuclear DNA sequences (ND1 and RAG2 genes, respectively), and morphological examination, we provide evidence for the existence of at least four distinct evolutionary lineages within this complex: Madascincus stumpffi; Madascincus arenicola sp. nov. from northern Madagascar; and two cryptic species morphologically similar to the name-bearing types of M. polleni and M. intermedius. The two latter species, although genetically distinct, appear to be morphologically indistinguishable and their taxonomic status cannot be resolved until a better sampling will be available.


Botany ◽  
2014 ◽  
Vol 92 (11) ◽  
pp. 815-820 ◽  
Author(s):  
Khosrow Chehri

Members of Fusarium solani species complex (FSSC) are frequently isolated from soils, food, feeds, trees, and to some extent from humans and other animals. The taxonomic status of these fungi is being revised but no attempt has been made to identify those isolated in Iran, a mountainous country with a high biodiversity. The objective of the present research was to study the phylogenetic diversity of FSSC strains recovered from soils in Iran by analyzing morphological characteristics and DNA sequences. A total of 65 strains belonging to the FSSC were recovered from agricultural soils in western Iran. Based on differences in their morphological characters, 25 strains were selected for phylogenetic analysis employing translation elongation factor-1α (tef1) and internal transcribed spacer (ITS) region sequences. Comparisons of DNA sequence data revealed that all isolates belonged to Fusarium falciforme, Fusarium keratoplasticum, Fusarium petroliphilum, the unnamed species FSSC 5, and unknown species of Fusarium, which represents a new lineage within members of Clade 3. Based on morphological features and phylogenetic study, F. keratoplasticum and F. petroliphilum were reported for the first time in Iran.


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