Up to three nominal species of the cyprinid fish genus Poropuntius (i.e. P. deauratus Valenciennes in Cuvier Valenciennes 1842, P. normani Smith 1931, and P. smedleyi de Beaufort 1933) have been ...reported to occur in Peninsular Malaysian freshwater ecosystems. However, low morphological differentiation among species of Poropuntius causes confusion and it is still unknown how many valid species of Poropuntius occur in this region. The goal of this study is to review the taxonomic status of Poropuntius in Peninsular Malaysia by using morphological and molecular characters. Principal Component Analysis (PCA) on a morphometric dataset including 281 specimens of Poropuntius from Peninsular Malaysia and P. normani from Thailand (type locality) failed to identify non-overlapping clusters within sampled specimens. A phylogenetic tree based on cytochrome oxidase subunit I (COI) showed intraspecific levels of genetic differentiation within Poropuntius of Peninsular Malaysia and the specimens of P. normani from Thailand form a monophyletic group. Our results strongly support the presence of only one species of Poropuntius in Peninsular Malaysia, P. normani. We demonstrate that P. smedleyi described from Johor, southern Peninsular Malaysia, is a junior synonym of P. normani. The previous reports of the presence of P. deauratus in Peninsular Malaysia are doubtful because this species was described from Vietnam where, in all evidence, it is endemic.
Two new species of Zeuxo Templeton, 1840 are described, one from Korea (Z. koreaensis), belonging to the Z. normani (Richardson, 1905) species complex, and one from Turkey (Z. turkensis). Two other ...Zeuxo species (Z. exsargasso Sieg, 1980 and Z. holdichi Bamber, 1990) are redescribed. The species Z. paranormani Sieg, 1980 is demoted to a junior synonym of Z. normani, while the 'Zeuxo normani' from Australia is raised to full species rank under the name Z. edgari.
The complete mitochondrial genome of the Cyprinodontiformes fish Poropanchax normani was studied in this study. The size of the entire mitochondrial genome was 16,878 bp, and the total length of the ...encoding sequence was 11,435 bp, accounting for 67.75%, encoding 3800 amino acids in total. Genome base compositions were: A was 27.30%, C was 28.30%, G was 16.17%, and T was 28.23%. ND2 and CO1 started with GTG, and other protein-coding genes started with ATG. ND1, ND2, and ND3 ended with TAG, respectively, CO2 and ND4 ended with a single T, and other PCGS ended with TAA. The ribosomal RNA lengths of 12S and 16S were 950 bp and 1690 bp, respectively. The control area (D-loop) was 1194 bp in size and ranged from 15,685 to 16,878 bp. It showed negative GC skew value (-0.2728) and negative AT skewness (-0.0168). Phylogenetic analysis showed that P. normani was most closely related to Xenotoca eiseni. The complete sequence of the mitochondrial genome will provide a new perspective for classification and help to draw a more complete picture of species diversity within the Cyprinodontiformes.
In this study, the phylogeographic patterns of nuclear, ribosomal and mtDNA gene fragments of five tanaidacean species (Zeuxo, Tanaidae) from the Atlantic, Pacific and Mediterranean Sea were ...investigated. We aimed to interpret results in the framework of current hypotheses on the distribution of small invertebrates with very limited dispersal ability. Evidence for a surprisingly high genetic divergence was found for intertidal tanaidaceans from the North Atlantic. This is a result of poor dispersal potential, as tanaidaceans have direct development, no pelagic stage, and very limited swimming capacity. However, lower genetic divergence was found between an intertidal tanaid species from the North Atlantic and two from the North Pacific, which suggests a scenario of recent colonization following the last glacial maximum. The species Zeuxo normani was found to be a species complex consisting, at least, of Z. normani (California), Z. cf. normani (Japan), Z. cf. normani (Australia), Z. sp. A (Korea), and Z. holdichi (Spain and France). Our results showed that traditional species identification underestimates tanaidacean diversity and that what have been previously perceived as reliable diagnostic morphological characters, are, however, variable and unreliable.Original Abstract: En este estudio, investigamos los patrones filogeograficos de fragmentos de ADN nuclear, ribosomico y mitocondrial de 5 especies de tanaidaceos (Zeuxo, Tanaidae) del Atlantico, Pacifico y Mediterraneo. Nos propusimos interpretar los resultados en el marco de hipotesis sobre la distribucion de pequenos invertebrados con limitada capacidad de dispersion. Encontramos evidencia de una sorprendentemente alta diferenciacion genetica para tanaidaceos del medio intermareal del Atlantico Norte. Esto es resultado de una limitada capacidad de dispersion, ya que los tanaidaceos poseen desarrollo directo, carecen de estadios pelagicos, y una limitada capacidad natatoria. Sin embargo, encontramos una baja diferenciacion genetica para una especie de tanaidaceo del Atlantico Norte y dos del Pacifico Norte, lo que sugiere un escenario de reciente colonizacion tras la ultima glaciacion. La especie Zeuxo normani constituye un complejo de especies que, al menos, agrupa a Z. normani (Califonia), Z. cf. normani (Japon), Z. cf. normani (Australia), Z. sp. A (Corea) y Z. holdichi (Espana y Francia). Nuestros resultados mostraron que la forma tradicional de identificar tanaidaceos subestima su diversidad y que lo que previamente se consideraron como caracteres morfologicos claramente diferenciadores son, sin embargo, variables y poco fiables.
We examined the morphology of the fertilized egg and the fine structure of fertilized egg envelopes of
Poropanchax normani
belonging to the family Poeciliidae, also known as Norman’s lampeye using ...light and electron microscopes. The fertilized eggs with narrow perivitelline space were found to be spherical and demersal, additionally containing small oil droplets in the vitelline membrane. Further, a bundle of adhesive filaments was observed to be present on one side of the fertilized egg. These filaments possessed remarkably high elasticity and were approximately 1-3 mm in length. The size of the fertilized egg was determined to be about 1.49 ± 0.07 mm (
n
= 30). The outer surface appeared smooth, and adhesive filaments originating at different location of the surface of the envelope were found to be distributed around the egg envelope and were joined together to form a single long bundle in scanning electron microscopic observation. A peak-like structure formed of several straight wrinkles was observed around the micropyle. However, the complete structure of the micropyle could not be studied due to the depth at which it was located. Additionally, the total thickness of the egg envelope was ascertained to be approximately12.5–14.5 μm. The egg envelope consisted of two distinct layers, an outer electron dense layer and an inner lamellar layer, further consisting of 10 sublayers of varying thicknesses. Collectively, it was observed that the morphological characteristics of the fertilized egg, fine structures surrounding the micropyle, outer surface, adhesive structure consisting adhesive filaments, and sections of fertilized egg envelope displayed species specificity.
Environmental conditions can affect the morphology and distribution of sponges. In particular, depth is known to influence the morphology of shallow-water sponges; however, the influence of depth on ...deep-water sponges has never been investigated. Although boreal Geodiidae (Demospongiae, Astrophorida) are deep-water species, in fjords and along the Norwegian coast Geodia barretti, G. simplicissima, and Pachymatisma normani can occasionally be found at shallow depths (20–40 m). In this study, we examine new shallow specimens from the Norwegian coast to compare their morphological and molecular characteristics with those of their deep-water counterparts. Morphology was studied at the level of the organism, skeletal organization, and the spicules, and a fragment of the cytochrome oxidase 1 gene was sequenced for shallow and deep specimens. Twelve specimens of Geodia spp. and five specimens of P. normani were collected in shallow waters. The majority of the Geodia spp. were identified as G. simplicissima, a species that has not been reported since its original description in 1931. However, we propose that G. simplicissima, only found in shallow waters, is a junior synonym of G. barretti. When comparing shallow and deep-water specimens of G. barretti and P. normani, we found phenotypic differences with respect to color, external morphology, cortex organization, and, above all, spicule morphology. In shallow specimens, microrhabds, sterrasters, and triaenes were smaller and irregular or underdeveloped. Oxyasters and strongylasters were normal in form, but smaller. We hypothesize that the lower silica concentration in shallow waters is primarily responsible for the disruption of spiculogenesis in shallow-water specimens of G. barretti and P. normani. The underdeveloped sterrasters observed in shallow-water specimens provide new insights into the formation of these particular microscleres. Finally, we discuss how the colonization of shallow waters by deep-water sponges may have strongly influenced spicule evolution and speciation.
A fossil cave and associated sediments and fossil fauna located on the Greek island of Rhodes in the eastern Aegean Sea is reported here, and the depositional history discussed. The sediments were ...deposited during the late Pliocene, in the interstitial space between basement boulders of up to 1500 tons. The depositional history of the cave comprises eight stages. From initial flooding, the basin experienced a continuous transgression with sea‐level rise in excess of 500 m, followed by a rapid, forced regression of similar magnitude. The recognition of a succession of fossil communities illustrates this transgression, with a seemingly abrupt shift from endolithic to epilithic biota dominance late in the transgressive cycle. The communities recording the increasing water depth from 0 to >150 m are: The Gatrochaenolithes torpedo (bivalve boring) and Entobia gonioides (sponge boring) ichnocoenosis, with peak distribution between 0 and 1 m water depth; the E. gonioides – E. magna ichnocoenosis, with 1–5 m depth peak distribution; the exclusive E. magna ichnocoenosis, with 5–40 m depth peak distribution; and the E. gigantea ichnocoenosis, with a peak distribution approaching 150–200 m. Below this depth, an epilithic community without boring organisms takes over, characterized by the calcareous sponge Merlia cf. normani, and the inarticulate brachiopod Novocrania turbinata. Simultaneously with the succession of the endo‐ and epilithic cave wall fossil communities, skeletal calcarenite accumulated on the cave floor; the erosional remnants of this sediment are insufficient to further expand the overall transgression–regression model.
Skeletal structures, especially the clasper, neurocranium and scapulocoracoids have been widely used to characterize and describe new species of elasmobranchs. Intra and interspecific variation of ...scapulocoracoids in 3 species of Psammobatis (n=67) from the Southwest Atlantic were analyzed to assess its utility as a diagnostic character in skates. Moreover, based on scapulocoracoids and body morphometric analysis, the validity of Psammobatis parvacauda McEachran, 1983 was evaluated. A remarkable sexual dimorphism in scapulocoracoids was observed in all species in accordance with original descriptions, which was also evident in the Principal Component (PCA) and Discriminant Analyses. The number and arrangement of post-dorsal and post-ventral fenestra was highly variable at intra-specific level, in contrast with original descriptions. Particularly, one of the morphotypes observed in females of P. normani was identical to the one registered in P. parvacauda. Results showed intraspecific variation in this structure, as was previously observed in Sympterygia species. Therefore, this structure should not be used as a diagnostic character in skates, at least for these genera. Regarding body morphometry the PCA showed that P. parvacauda grouped with P. normani females and the cross-validated analysis showed that P. parvacauda was classified in the group of P. normani females. P. parvacauda is only known for its original description (around Malvinas/Falkland Islands) and a likely second specimen, but our analyses revealed lack of diagnostic characteristics. Based on observation and measurement in the holotype of P. parvacauda, and comparisons with congeneric the species is here synonymized with P. normani.
Parafilaroides normani is a metastrongyloid nematode of clinical relevance in some species of pinnipeds. The taxonomy, biology and epidemiology of this and related species are not well understood. ...Mitochondrial (mt) DNA can provide markers for studies in these areas, but genetic data are scant. Here, we characterised the mt genome of P. normani. Adults of this nematode were collected from Arctocephalus pusillus doriferus from Phillip Island, Victoria, Australia, and genomic DNA was extracted from individuals. The complete mt genome was amplified from DNA from a single adult male by long-range PCR, as two overlapping amplicons (~5 and ~10 kb), and then sequenced employing 454 technology (Roche). The mt genome was assembled from reads of ~300 bp and annotated using an established bioinformatic pipeline. This circular mt genome is 13,411 bp and contains two ribosomal RNA, 12 protein-coding and 22 transfer RNA genes, consistent with those of other lungworms studied to date. This mt genome is intended to provide a source of genetic markers for future investigations of the biology, epidemiology and systematics of Parafilaroides spp. and related lungworms.
An assemblage of freshwater fishes inhabiting a medium‐sized stream in tropical central Vietnam was investigated with respect to spatial and trophic distribution. Point‐abundance sampling, gut ...content analysis and relative intestine length yielded interspecific differences in niche expression. Conspecific juvenile and adult habitat and feeding niches were also distinct. Niche differences arose mainly from differences in current velocity, substrata and foraging preferences. Extreme specializations, such as selective feeding on hard incustrations of cyanobacteria by adult Annamia normani, were present. The low niche overlap suggests that this tropical fish assemblage is structured by competitive interactions.
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