Molecular Classification of the Earthworm Aporrectodea trapezoids and the Effect of Sodium Nitroprusside and Norepinephrine on the Contractility of Crop and Gizzard Smooth Muscle

Background: Earthworms are considered as one of the ecologically important invertebrates with highly cryptic genetic diversity. Since the morphological methods of classification are unprecise, it is necessary to classify the species depending on molecular bases using PCR techniques. In addition, studying the effect of some agonists such as Sodium nitroprusside (SNP) and Norepinephrine (NE) on the smooth muscle of earthworm is yet poorly studied.

Integrated analysis of the ringneck snake Diadophis punctatus complex (Colubridae: Dipsadidae) in a biodiversity hotspot provides the foundation for conservation reassessment

Species classification may not reflect the underlying/cryptic genetic diversity and focusing on groups that do not represent historically independent units can misdirect conservation efforts. The identification of evolutionarily significant units (ESUs) allows cryptic genetic diversity to be accounted for when designating conservation priorities. We used multi-locus coalescent-based species delimitation methods and multivariate analyses of morphological data to examine whether the subspecies merit conservation recognition and infer the ESUs in ringneck snakes (Diadophis punctatus) throughout the California Floristic Province. Species delimitation methods failed to recover groups consistent with designated subspecies and instead inferred three well supported, mostly geographically isolated lineages. Divergence time estimates suggest that the divergences were driven by historical isolation associated with Pleistocene climate shifts. We found a correlation between increased morphological differentiation and time since divergence, and greater niche similarity between the more recently diverged eastern California and western California groups. Based on these results, we propose that the morphological similarities are due to a combination of morphological conservatism and evolutionary stasis. Our study provides the foundation necessary to re-assess the biodiversity and conservation status of ringneck snakes and offers an important step in unveiling the diversity within the western portion of the genus’ range.

From taxonomic deflation to newly detected cryptic species: Hidden diversity in a widespread African squeaker catfish

Cryptic genetic diversity and erroneous morphological species determination represent frequent problems in biodiversity research. Here, examination of 138 specimens of Synodontis (Mochokidae, Siluriformes) from the Nile River and Lake Turkana revealed the presence of both S. schall-like and S. frontosus-like morphotypes, with a phenotypic gradient between them. We concluded phylogenetic and population genetic analyses based on two mitochondrial and one nuclear marker including 131 coxI (565 bp), 96 cytb (973 bp) and 19 RAG2 (896 bp) sequences from the Nile-Turkana population, plus additional GenBank data of Synodontis spp. Whilst nuclear data were inconclusive, mitochondrial sequences suggested that both morphotypes and intermediate forms are conspecific. The results imply probable synonymy of S. frontosus with S. schall. Conversely, a strong biogeographical signal was revealed among widely distributed and supposedly conspecific S. schall-like catfish of the Nilo-Sudanian ichthyological province. Synodontis schall sensu stricto (=Eastern clade), as defined by type locality in the Nile, is apparently restricted to the eastern part of the Nilo-Sudanian ichthyological province (e.g. Nile, Turkana, Chad). Synodontis schall Western clade (Senegambia, Niger, Chad) most probably represents a cryptic taxon, unrecognized thus far due to the absence of distinctive morphological differences.

DNA barcoding of British mosquitoes (Diptera, Culicidae) to support species identification, discovery of cryptic genetic diversity and monitoring invasive species

Correct mosquito species identification is essential for mosquito and disease control programs. However, this is complicated by the difficulties in morphologically identifying some mosquito species. In this study, variation of a partial sequence of the cytochromecoxidase unit I (COI) gene was used for the molecular identification of British mosquito species and to facilitate the discovery of cryptic diversity, and monitoring invasive species. Three DNA extraction methods were compared to obtain DNA barcodes from adult specimens. In total, we analyzed 42 species belonging to the generaAedesMeigen, 1818 (21 species),AnophelesMeigen, 1818 (7 species),CoquillettidiaTheobald, 1904 (1 species),CulexLinnaeus, 1758 (6 species),CulisetaFelt, 1904 (7 species), andOrthopodomyiaTheobald, 1904 (1 species). Intraspecific genetic divergence ranged from 0% to 5.4%, while higher interspecific divergences were identified betweenAedesgeminusPeus, 1971/Culisetalitorea(Shute, 1928) (24.6%) andAe.geminus/An.plumbeusStephens, 1828 (22.5%). Taxonomic discrepancy was shown betweenAn.daciaeLinton, Nicolescu & Harbach, 2004 andAn.messeaeFalleroni, 1828 indicating the poor resolution of theCOIDNA barcoding region in separating these taxa. Other species such asAe.cantans(Meigen, 1818)/Ae.annulipes(Meigen, 1830) showed similar discrepancies indicating some limitation of this genetic marker to identify certain mosquito species. The combination of morphology and DNA barcoding is an effective approach for the identification of British mosquitoes, for invasive mosquitoes posing a threat to the UK, and for the detection of hidden diversity within species groups.