The biology of a landlocked form of the normally catadromous salmoniform fish Galaxias maculatus (Jenyns). II. Morphology and systematic relationships

1971 ◽  
Vol 22 (2) ◽  
pp. 125 ◽  
Author(s):  
DA Pollard
Keyword(s):  
Species Complex ◽  
The Other ◽  
Morphological Evidence ◽  
Galaxias Maculatus ◽  
Systematic Relationships ◽  
Lacustrine Form ◽  
Probable Origin ◽  
Western Victoria ◽  
Behavioural Evidence ◽  
Ecological Race

Following a brief outline of the systematic relationships of a number of species comprising the Galaxias maculatus species complex, the morphology of the "landlocked jollytail", a lacustrine galaxiid from Lake Modewarre (south-western Victoria), is described and compared with that of the normally catadromous stream dwelling species G. maculatus and a number of other closely related forms belonging to this complex. The probable systematic status of the landlocked jollytail and its relationship to the other forms included in the G. maculatus species complex are then discussed in the light of both the above morphological evidence, and ecological and behavioural evidence from a previous study of the life cycle and discussion of the probable origin of this lacustrine form. The conclusion is drawn that the landlocked jollytail should probably be regarded as no more than an isolated "ecological race" of the normally catadromous stream-dwelling species, G. maculatus.

The biology of a landlocked form of the normally catadromous salmoniform fish Galaxias maculatus (Jenyns). V. Composition of the diet

1973 ◽  
Vol 24 (3) ◽  
pp. 281 ◽  
Author(s):  
DA Pollard
Keyword(s):  
Fish Species ◽  
Stomach Contents ◽  
The Other ◽  
New Method ◽  
Food Type ◽  
Chironomid Larvae ◽  
Galaxias Maculatus ◽  
Benthic Food ◽  
Stomach Contents Analysis ◽  
Western Victoria

The composition of the diet of a landlocked form of the normally catadromous stream-dwelling fish Galaxias maculatus from Lake Modewarre in south-western Victoria was studied using a new method of stomach contents analysis based on the principle of ranking. The overall diet of this landlocked fish was found to consist mainly of amphipods, chironomid larvae, and copepods (basic food types), with other groups of crustaceans (cladocerans and ostracods) and insects (trichopteran and zygopteran larvae) being of lesser importance (secondary food types), and a few other incidental food types occurring in only small amounts. The diet of this landlocked form thus consists mainly of crustaceans, in contrast to that of the stream-dwelling form which comprises mainly insects. There was a change in the pattern of feeding in the landlocked fish with growth, the smaller fish eating more of the smaller planktonic and the larger fish more of the larger littoral-benthic food organisms. Amphipods were the dominant food type during all seasons except autumn, when copepods were dominant. Cladocerans were also important when they bloomed in summer, and chironomid adults when they swarmed in autumn. Selection coefficients indicated that those food types which were dominant in the diet were actively selected and those that were unimportant were avoided. This landlocked galaxiid was found to share most of the available food resources with the other four fish species found in the lake, and can be broadly classified as a euryphagic carnivore.

Resolving the Lourinia armata (Claus, 1866) complex with remarks on the monophyletic status of Louriniidae, Monard 1927 (Copepoda: Harpacticoida)

Zootaxa ◽  
2021 ◽  
Vol 5051 (1) ◽  
pp. 346-386
Author(s):  
SÜPHAN KARAYTUĞ ◽  
SERDAR SAK ◽  
ALP ALPER ◽  
SERDAR SÖNMEZ
Keyword(s):  
Comparative Evaluation ◽  
Species Complex ◽  
Detailed Examination ◽  
The Other ◽  
Phylogenetic Position ◽  
Nicobar Island ◽  
Other Hand ◽  
The Family ◽  
Close Relationship ◽  
Almost All

An attempt was made to test if Lourinia armata (Claus, 1866)—as it is currently diagnosed—represents a species complex. Detailed examination and comparisons of several specimens collected from different localities suggest that L. armata indeed represents a complex of four closely related morphospecies that can be differentiated from one another by only detailed observations. One of the four species is identified as Lourinia aff. armata and the other three species are described as new to science and named as Lourinia wellsi sp. nov., L. gocmeni sp. nov., and L. aldabraensis sp. nov. Detailed review of previous species records indicates that the genus Lourinia Wilson, 1924 is distributed worldwide. Ceyloniella nicobarica Sewell, 1940, originally described from Nicobar Island and previously considered a junior subjective synonym of L. armata is reinstated as Lourinia nicobarica (Sewell, 1940) comb. nov. on the basis of the unique paddle-shaped caudal ramus seta V. It is postulated that almost all of these records are unreliable in terms of representing true Lourinia aff. armata described herein. On the other hand, the comparative evaluation of the illustrations and descriptions in the published literature indicates the presence of several new species waiting to be discovered in the genus Lourinia.                 It has been determined that, according to updated modern keys, the recent inclusion of the monotypic genus Archeolourinia Corgosinho & Schizas, 2013 in the Louriniidae is not justified since Archeolourinia shermani Corgosinho & Schizas, 2013 does not belong to this family but should be assigned to the Canthocamptidae. On the other hand, it has been argued that the exact phylogenetic position of the Louriniidae still remains problematic since none of the diagnostic characters supports the monophyly of the family within the Oligoarthra. It has also been argued that the close relationship between Louriniidae and Canthocamptidae is supported since both families share the homologous sexual dimorphism (apophysis) on P3 endopod. The most important characteristic that can possibly be used to define Louriniidae is the reduction of maxilliped.  

scholarly journals Distribution of naked amoebae in the soils of the steppe zone of Ukraine

2020 ◽  
pp. 159-166
Author(s):  
M. Patsyuk ◽  
Keyword(s):  
Cluster Analysis ◽  
Multidimensional Scaling ◽  
Species Complex ◽  
Steppe Zone ◽  
Common Species ◽  
Molecular Clusters ◽  
The Other ◽  
Steppe Region ◽  
Species Complexes ◽  
Naked Amoebae

As a result of the study, in the steppe zone of Ukraine (Odessa, Mykolaiv, Kirovohrad region), 12 species of naked amoebas were identified, which according to the modern Eukaryot system belong to three molecular clusters Tubulinea Smirnov et al., 2005, Discosea Cavalier-Smith, 2004., Discoba Simpson and Hampl et al., 2009. This species Vahlkampfia sp. (1), Vahlkampfia sp. (2), Deuteramoeba mycophaga Page, 1988, Saccamoeba stagnicola Page, 1974, Vexillifera sp., Vannella sp. Ripellaplatypodia Smirnov, Nassonova, Chao et Cavalier-Smith, 2007, Cochliopodium sp. (1), Mayorella sp., Thecamoeba striata Penard, 1890, Stenamoeba stenopodia (Page, 1969) Smirnov et al., 2007, Acanthamoeba sp. (1). In the studied steppe soils, the most common were Vahlkampfia sp. (2), S. stenopodia, Vahlkampfia sp. (1), Vexillifera sp., Cochliopodium sp. (1); the least common – R. platypodia, D. mycophaga, T. striata, Mayorella sp. As a result of the cluster analysis, it was found that the largest share of common species is observed between Mykolaiv and Kirovograd regions (0.71) and Odessa and Kirovograd regions (0.53); the smallest is between the Odessa and Mykolaiv regions (0.43). According to the results of cluster analysis, the faunistic complexes of soil species of amoebae of the steppe region of Ukraine are united into two clusters: one of them being complexes characteristic of the Odessa region, and the other complexes of the Mykolaiv and Kirovograd regions. According to the results of nonparametric multidimensional scaling, it is established that the species complex of soil amoebae in the Kirovograd and Mykolaiv regions is determined by the increased soil temperature and acidity, compared to the Odessa region. As for moisture, this factor has little effect on the species complexes amoebae steppe region of Ukraine.

scholarly journals Identification of a novel Candida metapsilosis isolate suggests ongoing hybridization.

2021 ◽  
Author(s):  
Caoimhe E. O'Brien ◽  
Bing Zhai ◽  
Mihaela Ola ◽  
Eoin Ó Cinnéide ◽  
Ísla O'Connor ◽  
...  
Keyword(s):  
Loss Of Heterozygosity ◽  
Mating Type ◽  
Small Proportion ◽  
Species Complex ◽  
The Other ◽  
Human Pathogens ◽  
Hybridization Event ◽  
Candida Metapsilosis ◽  
Genome Stabilization ◽  
Haplotype A

Candida metapsilosis is a member of the C. parapsilosis species complex, a group of opportunistic human pathogens. Of all the members of this complex, C. metapsilosis is the least virulent, and accounts for a small proportion of invasive Candida infections. Previous studies established that all C. metapsilosis isolates are hybrids, originating from a single hybridization event between two lineages, parent A and parent B. Here, we use MinION and Illumina sequencing to characterize a C. metapsilosis isolate that originated from a separate hybridization. One of the parents of the new isolate is very closely related to parent A. However, the other parent (parent C) is not the same as parent B. Unlike C. metapsilosis AB isolates, the C. metapsilosis AC isolate has not undergone introgression at the Mating Type-like Locus. In addition, the A and C haplotypes are not fully collinear. The C. metapsilosis AC isolate has undergone Loss of Heterozygosity (LOH) with a preference for haplotype A, indicating that this isolate is in the early stages of genome stabilization.

scholarly journals Plantago campestris (Plantaginaceae), a rare new species from southern Brazil, supported by phylogenomic and morphological evidence

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11848
Author(s):  
Gustavo Hassemer ◽  
Elliot M. Gardner ◽  
Nina Rønsted
Keyword(s):  
New Species ◽  
Species Complex ◽  
High Throughput Sequencing ◽  
Morphological Characters ◽  
High Elevation ◽  
Species Level ◽  
Morphological Evidence ◽  
Southern Brazil ◽  
A New Species ◽  
Iucn Criteria

High-throughput sequencing, when combined with taxonomic expertise, is a powerful tool to refine and advance taxonomic classification, including at the species level. In the present work, a new species, Plantago campestris, is described out of the P. commersoniana species complex, based on phylogenomic and morphological evidence. The main morphological characters that distinguish the new species from P. commersoniana are the glabrous posterior sepals and the slightly broader leaves. The new species is known from only three localities, all in natural high-elevation grasslands in Paraná and Santa Catarina states, southern Brazil. According to the IUCN criteria new species should be assessed as Endangered (EN). We present field photographs of P. campestris and related species, and we provide an identification key to the species previously included within the circumscription of P. commersoniana.

The Persevering Cytotaxonomy: Discovery of a Unique XX/XY Sex Chromosome System in Catfishes Suggests the Existence of a New, Endemic and Rare Species

2018 ◽  
Vol 156 (1) ◽  
pp. 45-55 ◽  
Author(s):  
Dinaíza A. Rocha-Reis ◽  
Karina de Oliveira Brandão ◽  
Lurdes F. de Almeida-Toledo ◽  
Rubens Pazza ◽  
Karine F. Kavalco
Keyword(s):  
Phylogenetic Analysis ◽  
Rare Species ◽  
Species Complex ◽  
Sex Chromosome ◽  
Supernumerary Chromosome ◽  
The Other ◽  
Allopatric Populations ◽  
Sex Chromosome System ◽  
Upper Paraná River ◽  
Upper Paraná River Basin

The genus Hypostomus has a broad geographic distribution in Brazilian rivers and comprises armored catfishes with a very complicated taxonomy due to the absence of morphological autapomorphies. The existence of nearly 10 allopatric populations with different karyotypes suggests that Hypostomusancistroides represents a species complex in the Upper Paraná River basin. In this paper, an unusual karyotype of an isolated H. aff. ancistroides population was investigated. All specimens of this sample have 2n = 66 chromosomes except for 1 male with 2n = 67, most likely due to a supernumerary chromosome. In this population, the sexes are dimorphic, the males are heterogametic, and an XX/XY sex chromosome system is present. Phylogenetic analysis using mitochondrial and nuclear DNAs indicated that this population forms a monophyletic group separate from the other populations of H.ancistroides and may represent an incipient species.

Four new species of Phrynus, Lamarck (Arachnida: Amblypygi) from Mexico

Zootaxa ◽  
2021 ◽  
Vol 4948 (2) ◽  
pp. 151-183
Author(s):  
DANIEL CHIRIVI JOYA
Keyword(s):  
New Species ◽  
Species Complex ◽  
Population Studies ◽  
The Other ◽  
Genetic Population ◽  
Male And Female ◽  
Taxonomic Information ◽  
Species Complexes ◽  
Morphologic Variation ◽  
Mexican Species

Mexico is the country with the largest diversity of the genus Phrynus (Amblypygi: Phrynidae); however, many species could remain hidden due to the conservative morphology of the group. Two of the Mexican species, P. operculatus, and P. jalisco show enough variation, between populations from different localities, to be considered as possible species complexes. The scarce taxonomic information of these species and the few analyses of their variation could cause misidentifications and sub estimation of the diversity. Specimens morphologically similar to P. operculatus from different Mexican localities were analyzed, using characters from the male and female genitals. Four new species are described, presenting illustrations of SEM for the male genitals. Details of the morphologic variation in this group of species are discussed, as well as the usefulness of sexual characters like the size proportions, and sclerotization in the female gonopods, and ornaments in males, to improve the diagnoses of the Mexican Phrynus. The known distribution of P. operculatus is large in comparison with those of the other species, after the result of this research, the possibility that it is a larger species complex is evident, thus, it is necessary to increase the morphologic and genetic population studies in this group. 

scholarly journals Species Delineation Within the Euwallacea fornicatus (Coleoptera: Curculionidae) Complex Revealed by Morphometric and Phylogenetic Analyses

2018 ◽  
Vol 2 (6) ◽  
Author(s):  
Demian F Gomez ◽  
James Skelton ◽  
M Sedonia Steininger ◽  
Richard Stouthamer ◽  
Paul Rugman-Jones ◽  
...  
Keyword(s):  
Species Complex ◽  
Phylogenetic Analyses ◽  
Integrated Approach ◽  
Type Specimen ◽  
Morphological Characters ◽  
Morphological Evidence ◽  
Pest Species ◽  
Species Delineation ◽  
Genetic Lineages ◽  
C Subunit

Abstract The ambrosia beetle Euwallacea fornicatus Eichhoff sensu lato is a complex of genetically divergent emerging pests responsible for damages to tree industries and ecosystems around the world. All lineages within the species complex are currently considered morphologically identical, presenting problems for their delineation and highlighting the shortcomings of species concepts based solely on type-specimen morphology. The objectives of this work were to 1) broaden the geographic sampling of the E. fornicatus complex in Asia, 2) reconstruct relationships between clades and populations, 3) find morphological characters or combinations of characters which are useful in delimiting the genetic lineages of the E. fornicatus species complex, and 4) propose taxonomic delimitation of species where morphology and phylogenetic identity correlate. Our integrated approach using molecular and morphological evidence suggests four clades that differ morphologically, but with overlap, therefore, cytochrome oxidase c subunit I (COI) barcoding remains necessary for assigning specimens to a clade. The following taxonomic changes are proposed: E. fornicatus (Eichhoff 1868) (= ‘Tea Shot Hole Borer Clade a’); E. fornicatior (Eggers 1923), stat. rev. (= ‘Tea Shot Hole Borer Clade b’); E. whitfordiodendrus (Schedl 1942), stat. rev. (= ‘Polyphagous Shot Hole Borer’); and E. kuroshio Gomez and Hulcr, sp. nov. (= ‘Kuroshio Shot Hole Borer’). This approach delivers a practical, evidence-based guidance for species delineation that can address overlapping variation in morphological characters of an emerging pest species complex.

scholarly journals Taxonomy of Micronesian monitors (Reptilia: Squamata: Varanus ): endemic status of new species argues for caution in pursuing eradication plans

2020 ◽  
Vol 7 (5) ◽  
pp. 200092
Author(s):  
Valter Weijola ◽  
Varpu Vahtera ◽  
André Koch ◽  
Andreas Schmitz ◽  
Fred Kraus
Keyword(s):  
New Species ◽  
The Other ◽  
Disjunct Distribution ◽  
Morphological Evidence ◽  
Mariana Islands ◽  
Separate Species ◽  
Natural Origin ◽  
Phylogenetic Studies ◽  
Human Introduction ◽  
Monitor Lizards

In the light of recent phylogenetic studies, we re-assess the taxonomy and biogeography of the Varanus populations distributed in the Micronesian islands of Palau, the Western Carolines and the Marianas. Whether these populations are of natural origin or human introductions has long been contentious, but no study has fully resolved that question. Here, we present molecular and morphological evidence that monitor lizards of the Varanus indicus Group reached both Palau and the Mariana Islands sometime in the late Pleistocene and subsequently differentiated into two separate species endemic to each geographical region. One species is confined to the Mariana Islands, and for these populations, we revalidate the name V. tsukamotoi Kishida, 1929. The other species has a disjunct distribution in Palau, the Western Carolines and Sarigan Island in the Northern Marianas and is herein described as V. bennetti sp. nov. Both species are most closely allied to each other, V. lirungensis and V. rainerguentheri , suggesting that colonization of Micronesia took place from the Moluccas. We discuss the biogeographic distributions of both species in the light of the likely colonization mechanism and previous arguments for human introduction, and we argue that bounties for Palauan populations are ill-advised and plans for eradication of some other populations must first demonstrate that they are, in fact, introduced and not native.

A new giant Vellozia (Velloziaceae) from Minas Gerais, Brazil with comments on the V. compacta complex and conservation

Phytotaxa ◽  
2014 ◽  
Vol 172 (1) ◽  
pp. 13 ◽  
Author(s):  
Ruy José Válka Alves ◽  
Alessandra Ribeiro Guimarães ◽  
Claudia De Moraes Rezende ◽  
Laura Di Spirito Braga ◽  
Nílber Gonçalves da Silva
Keyword(s):  
New Species ◽  
Species Complex ◽  
Chemical Constituents ◽  
Minas Gerais ◽  
The Other ◽  
Taxonomic Study ◽  
Anatomical Characters

A new giant Vellozia species from the Ouro Branco range, Minas Gerais, is described and compared morphologically to the other dracenoid species. Leaf-anatomical characters and a unique suite of chemical constituents which help to separate the new species from V. compacta, sympatric in the range, are provided. Furthermore we discuss the circumscription of V. compacta and argue that this binomial is applied to a species complex in need of further taxonomic study.

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