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1.
The present results are the effect of bioprospecting of an appropriate medium, which could optimize the quality and quantity of the microalga Pseudopiediastrum boryanum var. longicorne Reinsch biomass cultured in a laboratory photobioreactor for biosorption purposes. Four liquid media commonly used for cultivation of green algae of the genus Pediastrum were compared, including Knop's, Waris‐H, Chu's and L‐S2T2 media, which differed with respect to the composition and concentration of nutrients. A number of the parameters characterizing biomass growth, namely dry weight, optical density, chlorophyll a concentration, as well as morphological parameters characterizing the condition of the alga and its surface area indicating the potential sorption capacity (population structure, cell number, coenobium size and marginal cell size), showed a significant impact of culture medium on the growth of the microalga. The most productive culture was found in the L‐S2T2 medium containing organic substances in the form of peat and soil extracts, which could be crucial for biomass production and the area of potential sorption capacity.  相似文献   

2.
Phylogenetic reconstruction and species delimitation are often challenging in the case of recent evolutionary radiations, especially when postspeciation gene flow is present. Leopardus is a Neotropical cat genus that has a long history of recalcitrant taxonomic problems, along with both ancient and current episodes of interspecies admixture. Here, we employ genome-wide SNP data from all presently recognized Leopardus species, including several individuals from the tigrina complex (representing Leopardus guttulus and two distinct populations of Leopardus tigrinus), to investigate the evolutionary history of this genus. Our results reveal that the tigrina complex is paraphyletic, containing at least three distinct species. While one can be assigned to L. guttulus, the other two remain uncertain regarding their taxonomic assignment. Our findings indicate that the “tigrina” morphology may be plesiomorphic within this group, which has led to a longstanding taxonomic trend of lumping these poorly known felids into a single species.  相似文献   

3.
Previous morphometric studies based on linear measurements of female structures of the aculeus, mesonotum, and wing revealed the existence of seven morphotypes within the Anastrepha fraterculus cryptic species complex along the Neotropical Region. The current research followed linear and geometric morphometric approaches in 40 population samples of the nominal species Anastrepha fraterculus (Wiedemann) spread throughout the Meso-American and Pacific Neotropical dominions (including Mexico, Central America, Venezuela, Colombia, Ecuador, and Peru). The goals were to explore the phenotypic relationships of the morphotypes in these biogeographical areas; evaluate the reliability of procedures used for delimitation of morphotypes; and describe their current distribution. Findings determined that morphotypes previously recognized via the linear morphometrics were also supported by geometric morphometrics of the wing shape. In addition, we found an eighth morphotype inhabiting the highlands of Ecuador and Peru. Morphotypes are related into three natural phenotypic groups nominated as Mesoamerican-Caribbean lineage, Andean lineage, and Brazilian lineage. The hypothesis that lineages are not directly related to each other is discussed, supported by their large morphological divergence and endemicity in these three well-defined biogeographic areas. In addition, this hypothesis of the non-monophyly of the Anastrepha fraterculus complex is also supported by evidence from other authors based on molecular studies and the strong reproductive isolation between morphs from different lineages.  相似文献   

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Platyrrhinus is a diverse genus of small to large phyllostomid bats characterized by a comparatively narrow uropatagium thickly fringed with hair, a white dorsal stripe, comparatively large inner upper incisors that are convergent at the tips, and three upper and three lower molars. Eighteen species are currently recognized, the majority occurring in the Andes. Molecular, morphological, and morphometric analyses of specimens formerly identified as Platyrrhinus helleri support recognition of Platyrrhinus incarum as a separate species and reveal the presence of two species from western and northern South America that we describe herein as new ( Platyrrhinus angustirostris sp. nov. from eastern Colombia and Ecuador, north‐eastern Peru, and Venezuela and Platyrrhinus fusciventris sp. nov. from Guyana, Suriname, French Guiana, Trinidad and Tobago, northern Brazil, eastern Ecuador, and southern Venezuela). These two new species are sister taxa and, in turn, sister to Platyrrhinus incarum. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159 , 785–812.  相似文献   

8.
Recent investigations in the upper Río Huallaga in Peru revealed the presence of an intriguing species of the Loricariinae. To characterize and place this species within the evolutionary tree of the subfamily, a molecular phylogeny of this group was inferred based on the 12S and 16S mitochondrial genes and the nuclear gene F-reticulon4. The phylogeny indicated that this distinctive species was a member of the subtribe Loricariina. Given its phylogenetic placement, and its unusual morphology, this species is described as a new genus and new species of Loricariinae: Fonchiiloricaria nanodon. This new taxon is diagnosed by usually possessing one to three premaxillary teeth that are greatly reduced; lips with globular papillae on the surface; the distal margin of lower lip bearing short, triangular filaments; the premaxilla greatly reduced; the abdomen completely covered by plates, with the plates between lateral abdominal plates small and rhombic; a caudal fin with 14 rays; the orbital notch absent; five lateral series of plates; dorsal-fin spinelet absent; preanal plate present, large and solid, and of irregular, polygonal shape, the caudal peduncle becoming more compressed posteriorly for the last seven to 10 plates.  相似文献   

9.
An integrative approach by the congruence of genetics, morphology and ecological niche modelling (ENM) was used to delimit a new species of Hypanus (Rafinesque, 1818), a recently resurrected genus of marine stingrays comprising eight species, five of which occur in the western Atlantic. The species with the widest distribution, Hypanus americanus (Hildebrand and Schroeder, 1928), from the northeastern coast of the United States to southeastern Brazil, was demonstrated to be paraphyletic based on protein-coding mitochondrial genome analyses. This data set also indicates that the genetic distance between the new species Hypanus berthalutzae sp. nov. and its three closely related species (H. americanus, H. longus and H. rudis) varies from 0.82% to 3.14%. In addition, Bayesian Analysis of Population Similarity using the mitochondrial gene mt-nd2 supports the separation of H. berthalutzae sp. nov. (southwestern Atlantic) from its sister species H. rudis (eastern Atlantic). Similarly, morphological and morphometric analyses corroborated four morphotypes within the H. americanus species group and indicated the ventral caudal fold height and length and interspiracular and interorbital lengths as useful measurements to distinguish among them. Claspers of adult males also exhibit morphological differences among species. The ENM agreed with molecular and morphological analyses and delimits the distribution of H. berthalutzae sp. nov. to shallow areas close to shore along the Brazilian coast, from the mouth of the Amazon River to São Paulo State, including the northeastern oceanic islands, suggesting that the great outflow of fresh water and sediments and the Mid-Atlantic Ridge might act as barriers. The integration of these data to describe a new species provides information relevant to their conservation status, because all species of the H. americanus species group are under the “data-deficient” status.  相似文献   

10.
Alyssum ovirense (Brassicaceae) is disjunctly distributed in the eastern Alps, predominantly occurring in the southern limestone Alps, but with one isolated population on the Hochschwab massif in the northern limestone Alps. The closely related rare and narrow endemic A. wulfenianum is restricted to gravel beds in a few rivers in the southern Alps draining the distribution area of A. ovirense. Applying molecular (amplified fragment length polymorphism fingerprinting and sequencing of plastid and nuclear DNA), karyological (flow cytometry and chromosome counts) and morphometric methods to a set of populations sampled throughout the distribution range, we evaluated the status of the population on the Hochschwab massif and the relationship between high‐elevation A. ovirense and low‐elevation A. wulfenianum. The population on Hochschwab massif is hexaploid, morphologically clearly divergent and grows in vegetation patches and dense alpine grasslands, whereas southern Alpine A. ovirense inhabits sparsely vegetated limestone screes. Molecular data show that the former represents a genetically isolated lineage which is formally described as A . neglectum sp. nov. All populations from the southern limestone Alps, including A. wulfenianum, are diploid. Although A. wulfenianum is genetically nested in A. ovirense, its morphological and ecological differentiation justifies recognition at the subspecific level. As A. wulfenianum has priority over A. ovirense, the correct names are A. wulfenianum subsp. wulfenianum and A. wulfenianum subsp. ovirense. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 176 , 486–505.  相似文献   

11.
Abstract

The family Acanthoclinidae includes 10 species: Acanthoclinus fuscus Jenyns, 1842; Taumakoides littoreus ((Forster) Bloch & Schneider, 1801); T. rua n. sp.; T. marilynae n. sp.; T. matti n. sp.; Belonepterygion fasciolatum (Ogilby, 1889); Beliops xanthokrossos n. gen. et sp.; Acanthoplesiops indicus (Day, 1888); A. hiatti Schultz, 1953; and A. psilogaster n. sp. Acanthoclinus quadridactylus (Bloch & Schneider, 1801) and A. trilineatus Griffin, 1933, are reduced to synonymy under Taumakoides littoreus ((Forster) Bloch & Schneider, 1801).

Osteological and morpological character states, between and within genera, suggest that Acanthoclinus and Taumakoides are close to the stock from which the family is derived. There is also compelling evidence that T. matti is the least specialised species of Taumakoides. Progressive specialisation is evident in the remaining genera, with Acanthoplesiops being the most highly specialised.

The family occurs primarily in shallow waters of the Indian and western Pacific oceans; most of the species are found about New Zealand. The centre of origin of the Acanthoclinidae was probably on the Indian-Australian Plate (which includes the New Zealand continental shelf). Acanthoplesiops hiatti and A. indicus are considered to be endemics of the Pacific and African plates, respectively.

A key to species is included.  相似文献   

12.
ABSTRACT. Sixty-five members of the Ctypthecodinium cohnii species complex were analyzed for sequence differences within the D2 region of the 23S ribosomal RNA molecule. On the basis of 46 sequence differences the strains fell into 19 distinct ribosets (strains of identical sequence), some with many members. Members of four of the seven major sibling species (widespread breeding groups) were each found within single ribosets. Members of three other major sibling species were each, however, divided into two ribosets by a single sequence difference correlated with geographic separation and with previously reported electrophoretic polymorphisms of soluble enzymes within the sibling species. In addition to members of major sibling species, some ribosets include many minor sibling species (each represented by only one strain). Of 38 minor sibling species, 22 shared sequence with a major sibling species. Of these 22, 14 were identical in soluble enzymes to their related major sibling species or differed by only one of three enzymes. Other minor sibling species appear to have diverged extensively from any others in both rRNA sequence and electrophoretic profile. As a group, major sibling species differ markedly in the number of minor sibling species associated with them, suggesting differences in frequency of sexually isolating events in their past histories. These findings are discussed in the context of the previously proposed model of sympatric speciation.  相似文献   

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A phylogeny of West Palearctic Salamandridae based on 1208 bp of mtDNA sequences (300 bp of cytb, 346 bp of 12S rRNA and 562 bp of 16S rRNA) indicates the European brook newts (Euproctus) are polyphyletic. To reflect revised relationships, the Tyrrhenian species (E. montanus ( Savi, 1838 ) and E. platycephalus ( Gravenhorst, 1829 )) are retained in Euproctus Genè, 1839 , while the genus Calotriton Gray, 1858 is resurrected to include the Pyrenean brook newt ( Calotriton asper ( Dugès, 1852 ) comb. nov. ) and a new species from the massif of El Montseny, Catalonia, Spain, described herein as Calotriton arnoldi sp. nov. , which is both morphologically and genetically distinct. Although according to the principle of priority Megapterna Savi, 1838 should take precedence over Euproctus Genè, 1839 , for the sake of nomenclatural stability and in line with Art. 23.9.1 of the International Code of Zoological Nomenclature, Megapterna is considered a nomen oblitum and Euproctus a nomen protectum. The polyphyly of Euproctus (s.l.) contradicts previous, well‐accepted, biogeographical hypotheses and represents a clear case of convergence, involving several morphological traits and a unique reproductive behaviour that is advantageous in stream situations. Molecular dating suggests the Western brook newt lineage (C. asper+C. arnoldi) originated towards the end of the Miocene (8.3 ± 0.11 Mya) and is part of a well‐supported monophyletic assemblage, which also includes Neurergus kaiseri ( Schmidt, 1952 ) and a clade formed by Triturus karelinii ( Strauch, 1870 ), T. carnifex ( Laurenti, 1768 ), T. pygmaeus ( Wolterstoff, 1905 ) and T. marmoratus ( Latreille, 1800 ). Speciation separating E. montanus and E. platycephalus might have coincided with the onset of the Messinian salinity crisis. © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society, 2005, 145 , 555–582.  相似文献   

15.
A Chinese population of the little‐known freshwater hypotrich Uroleptus longicaudatus was investigated with emphasis on its living morphology and infraciliature. The characteristic, tripartite body consists of a narrowed (cephalized) anterior portion, a slender trunk, and a long, slender, and strongly contractile tail occupying up to 30% of body length. Contracted specimens with a tail length of about 12% closely resemble Uroleptus limnetis which has, like U. longicaudatus, its type locality on the East Coast of the United States so that it cannot be excluded that these two species are synonymous. Thus, we propose to subsume these and few other little‐known species, which are not clearly distinguishable at the present state of knowledge, as U. limnetis complex. The morphogenesis of U. longicaudatus proceeds as in most congeners. The phylogenetic analyses reveal that Uroleptus is a monophyletic group, but due to the lack of detailed morphological data of the populations sequenced so far, the relationships within this taxon remain obscure. For the objective determination of the tail length of hypotrichs, we propose the “1/3‐method”, which says that the tail commences at that body width which corresponds one‐third of the maximum width. Paruroleptus ophryoglena Gelei, 1954 is transferred to Uroleptus: Uroleptus ophryoglena (Gelei, 1954) comb. nov.  相似文献   

16.
Recent field studies revealed two new species of the genus Aglyptodactylus (Amphibia: Anura: Ranidae), which was hitherto considered as monotypic and confined to humid eastern Madagascar. Both new species, Aglyptodactylus laticeps sp. n. and Aglyptodactylus securifer sp. n. , occur syntopically in the deciduous dry forest of Kirindy in western Madagascar. In comparison to Aglyptodactylus madagascariensis from eastern rainforests, the new species A. laticeps shows a remarkable morphological divergence, which may be partly due to adaptations to burrowing habits in dry environments. Despite of the morphological differentiation, advertisement calls and osteology indicate that all three species of Aglyptodactylus are closely related. A phylogenetic analysis of the Madagascan ranid genera Aglyptodactylus, Mantella, Mantidactylus, Boophis , and Tomopterna (the latter including species from Madagascar, Africa, and Asia) strongly supports a sister group relationship of Aglyptodactylus with the ranine genus Tomopterna . We therefore transfer Aglyptodactylus from the Rhacophorinae to the Raninae and discuss implications of this rearrangement for ranoid systematics. The existence of the endemic genus Aglyptodactylus in Madagascar as well as its close phylogenetic relationships to Tomopterna confirm that the Raninae were already present on the Madagascan plate before its separation from Africa. The Madagascan Tomopterna labrosa shows several important differences both to Asian and to African species of the genus, and is therefore transferred from the subgenus Sphaerotheca (now restricted to Asia) to a new subgenus Laliostoma subgen. n .  相似文献   

17.
The diverse genus Ophion is almost entirely undescribed in the Nearctic region. In this paper we define the Ophion scutellaris species group. This species group is well-supported by analysis of DNA (ITS2, COI, and 28S D2-D3) and morphology. It includes the Palearctic species Ophion scutellaris and the Nearctic species Ophion idoneus. An integrative analysis of DNA, geometric wing morphometrics, classical morphometrics and qualitative morphology indicates that this species group contains a minimum of seven species in North America, although the full diversity of the group has likely not been sampled. Ophion clave Schwarzfeld, sp. n., Ophion aureus Schwarzfeld, sp. n., Ophion brevipunctatus Schwarzfeld, sp. n., Ophion dombroskii Schwarzfeld, sp. n., Ophion keala Schwarzfeld, sp. n. and Ophion importunus Schwarzfeld, sp. n. are described, and a key to the known Nearctic species of the Ophion scutellaris group is provided.  相似文献   

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