scholarly journals Osteology of Tucanoichthys tucano Géry and Römer, an enigmatic miniature fish from the Amazon basin, Brazil (Teleostei: Characiformes: Characidae)

2021 ◽  
Vol 71 ◽  
pp. 645-667
Author(s):  
George M. T. Mattox ◽  
Kevin W. Conway
Keyword(s):  
Amazon Basin ◽  
Freshwater Fishes ◽  
Molecular Data ◽  
Phylogenetic Position ◽  
Close Relative ◽  
Sensory Canal ◽  
The Family ◽  
Rio Negro Basin ◽  
Salminus Brasiliensis ◽  
Ossification Sequence

Miniaturization, the evolution of extremely small adult body size, is a common phenomenon across the lineages of freshwater fishes, especially in the Neotropics where over 200 species are considered miniature (≤26 mm in standard length [SL]). Close to 30% of all miniature Neotropical freshwater fishes belong to the family Characidae, several of which are of uncertain phylogenetic placement within the family. We investigate the skeletal anatomy of Tucanoichthys tucano, a species of uncertain phylogenetic position from the upper Rio Negro basin, reaching a maximum known size of 16.6 mm SL. The skeleton of Tucanoichthys is characterized by the complete absence of ten skeletal elements and marked reduction in size and/or complexity of others, especially those elements associated with the cephalic latero-sensory canal system. Missing elements in the skeleton of Tucanoichthys include those that develop relatively late in the ossification sequence of the non-miniature characiform Salminus brasiliensis, suggesting that their absence in Tucanoichthys can be explained by a simple scenario of developmental truncation. A number of the reductions in the skeleton of Tucanoichthys are shared with other miniature characiforms, most notably species of Priocharax and Tyttobrycon, the latter a putative close relative of Tucanoichthys based on molecular data.

scholarly journals Phylogenetic position and taxonomy of Cycloseris explanulata and C. wellsi (Scleractinia: Fungiidae): lost mushroom corals find their way home

2012 ◽  
Vol 81 (3) ◽  
pp. 125-146 ◽  
Author(s):  
Francesca Benzoni ◽  
Roberto Arrigoni ◽  
Fabrizio Stefani ◽  
Bastian T. Reijnen ◽  
Simone Montano ◽  
...  
Keyword(s):  
Molecular Study ◽  
Molecular Data ◽  
Phylogenetic Position ◽  
Distribution Data ◽  
Data Sets ◽  
Free Living ◽  
New Findings ◽  
The Family ◽  
Ecological Implications ◽  
History Of

The scleractinian species Psammocora explanulata and Coscinaraea wellsi were originally classified in the family Siderastreidae, but in a recent morpho-molecular study it appeared that they are more closely related to each other and to the Fungiidae than to any siderastreid taxon. A subsequent morpho-molecular study of the Fungiidae provided new insights regarding the phylogenetic relationships within that family. In the present study existing molecular data sets of both families were analyzed jointly with those of new specimens and sequences of P. explanulata and C. wellsi. The results indicate that both species actually belong to the Cycloseris clade within the family Fungiidae. A reappraisal of their morphologic characters based on museum specimens and recently collected material substantiate the molecular results. Consequently, they are renamed Cycloseris explanulata and C. wellsi. They are polystomatous and encrusting like C. mokai, another species recently added to the genus, whereas all Cycloseris species were initially thought to be monostomatous and free-living. In the light of the new findings, the taxonomy and distribution data of C. explanulata and C. wellsi have been updated and revised. Finally, the ecological implications of the evolutionary history of the three encrusting polystomatous Cycloseris species and their free-living monostomatous congeners are discussed.

High cryptic diversity in the kleptoparasitic genus Hyalorisia Dall, 1889 (Littorinimorpha: Capulidae) with the description of nine new species from the Indo-West Pacific

2020 ◽  
Vol 86 (4) ◽  
pp. 401-421 ◽  
Author(s):  
Giulia Fassio ◽  
Valeria Russini ◽  
Barbara Buge ◽  
Stefano Schiaparelli ◽  
Maria Vittoria Modica ◽  
...  
Keyword(s):  
Trophic Ecology ◽  
Molecular Data ◽  
Sympatric Species ◽  
Water Current ◽  
Phylogenetic Position ◽  
Nominal Species ◽  
West Pacific ◽  
Allopatric Species ◽  
Wide Range ◽  
The Family

ABSTRACT Species in the family Capulidae (Littorinimorpha: Capuloidea) display a wide range of shell morphologies. Several species are known to live in association with other benthic invertebrates—mostly bivalves and sabellid worms, but also other gastropods—and are believed to be kleptoparasitic filter feeders that take advantage of the water current produced by the host. This peculiar trophic ecology, implying a sedentary lifestyle, has resulted in highly convergent shell forms. This is particularly true for the genus Hyalorisia Dall, 1889, which occurs in deep water in the Caribbean and Indo-West Pacific provinces, with two nominal species recognized so far. Combining morphological, ecological and molecular data, we assessed the diversity of the genus, its phylogenetic position inside the family and its association with its bivalve host, the genus Propeamussium de Gregorio, 1884 (Pectinoidea), resulting in the description of nine new cryptic species. When sympatric, species of Hyalorisia are associated with different host species, but the same species of Propeamussium may be the host of several allopatric species of Hyalorisia.

Phylogenetic relationships of the subfamily Pyrgulinae (Gastropoda: Caenogastropoda: Hydrobiidae) with emphasis on the genus Dianella Gude, 1913

Zootaxa ◽  
2005 ◽  
Vol 891 (1) ◽  
pp. 1 ◽  
Author(s):  
Magdalena Szarowska ◽  
Andrzej Falniowski ◽  
FRANK Riedel ◽  
Thomas Wilke
Keyword(s):  
Type Species ◽  
Sister Group ◽  
Molecular Data ◽  
Character Evolution ◽  
Phylogenetic Position ◽  
Sister Group Relationship ◽  
Data Sets ◽  
Sequencing Data ◽  
The Family ◽  
Anatomical Characters

The phylogenetic position of the subfamily Pyrgulinae within the superfamily Rissooidea has been discussed very controversially. Different data sets not only led to different evolutionary scenarios but also to different systematic classifications of the taxon. The present study uses detailed anatomical data for two pyrgulinid taxa, the type species of the subfamily, Pyrgula annulata (Linnaeus, 1767), and the type species of the little known genus Dianella, D. thiesseana (Kobelt, 1878), as well as DNA sequencing data of three gene fragments from representatives of eight rissooidean families to A) infer the phylogenetic position of Pyrgulinae with emphasis on its relationships within the family Hydrobiidae, B) to study the degree of concordance between anatomyand DNAbased phylogenies and C) to trace the evolution of anatomical characters along a multi-gene molecular phylogeny to find the anatomical characters that might be informative for future cladistic analyses. Both anatomical and molecular data sets indicate either a very close or even sister-group relationship of Pyrgulinae and Hydrobiinae. However, there are major conflicts between the two data sets on and above the family level. Notably, Hydrobiidae is not monophyletic in the anatomical analysis. The reconstruction of anatomical character evolution indicates that many of the characters on which the European hydrobioid taxonomy is primarily based upon are problematic. The inability to clearly separate some hydrobiids from other distinct families based on those characters might explain why until only a few years ago, "Hydrobiidae" was a collecting box for numerous rissooidean taxa (mostly species with shells small and lacking any characteristic features). The present study not only stresses the need for comprehensive molecular studies of rissooidean taxa, it also demonstrates that much of the problems surrounding anatomical analyses in rissooidean taxa are due to the lack of comprehensive data for many representatives. In order to aid future comparativeanatomical studies and a better understanding of character evolution in the species-rich family Hydrobiidae, detailed anatomical descriptions for P. annulata and D. thiesseana are provided.Key words: Pyrgulinae, Pyrgula, Dianella, Hydrobiidae, phylogeny, DNA, anatomy, Greece

scholarly journals Cruciglanis, a new genus of Pseudopimelodid catfish (Ostariophysi: Siluriformes) with description of a new species from the Colombian Pacific coast

2006 ◽  
Vol 4 (2) ◽  
pp. 147-156 ◽  
Author(s):  
Armando Ortega-Lara ◽  
Pablo Lehmann A.
Keyword(s):  
New Genus ◽  
The Other ◽  
Dark Spot ◽  
Phylogenetic Position ◽  
Caudal Fin ◽  
Sensory Canal ◽  
The Pacific ◽  
The Family ◽  
Pacific Slope

Cruciglanis pacifici, gen. et sp. nov., is described from the Dagua and Anchicaya Rivers on the Pacific slope of Colombia. The new genus is differentiated from the other genera in the family by the presence of an ossified crucifix-shaped second basibranchial; ectopterygoid bone shaped as an inverted comma, with its distal end narrow and directed medially towards the mesopterygoid; anterior fontanel elongated, reaching a transverse line at sensory canal opening of the sphenotic bone; caudal fin emarginated with rounded edges and ventral lobe more developed than the dorsal lobe; caudal fin with a dark spot from its base and fused with the peduncular spot, covering the anterior three quarters of its length, distal rim totally hyaline. Coloration of the species is described in vivo, and the shared diagnostic characters with the other genera within the Pseudopimelodidae are discussed. The phylogenetic position of the new genus is proposed and new insights in the family interrelationships are presented.

Early embryology of Vochysiaceae and some insights into its phylogeny and intrafamilial taxonomy

Phytotaxa ◽  
2020 ◽  
Vol 443 (3) ◽  
pp. 211-257
Author(s):  
RENATA CARMO-OLIVEIRA ◽  
LUCIANA NASCIMENTO CUSTÓDIO ◽  
BERTA LANGE DE MORRETES ◽  
PAULO EUGÊNIO OLIVEIRA
Keyword(s):  
Developmental Stages ◽  
Embryo Sac ◽  
Sister Group ◽  
Molecular Data ◽  
Phylogenetic Position ◽  
Its Phylogeny ◽  
The Family

Embryological data provides insights into the taxonomy and evolution of angiosperms.  Vochysiaceae is a mostly Neotropical family whose phylogenetic position was greatly influenced by reconstructions based on molecular data, and despite its monosymmetric and oligostemonous flowers, was included as a sister group of polysymmetric and polystemonous Myrtaceae. However, molecular data has yet to resolve the relationships between the genera inside the family. We analysed the early embryology of some species of five out of the six generally accepted Neotropical genera using sequential histological analyses to compare the microsporogenesis and gametogenesis and megasporogenesis and gametogenesis between clades and with the embryology of the well-studied Myrtales. We observed some marked differences in timing and developmental stages, which somewhat corroborate the clades defined from molecular data. Multiple archesporium and embryo sacs, as well as megagametophyte maturation and fertilization long after anthesis, characterized the Qualea-Ruizteranea-Callisthene (QRC) clade, while single embryo sac mature at anthesis characterized the Vochysia-Salvertia (VS) clade. Tri-cellular pollen only occurred in Salvertia convallariodora. Seven of the eight main embryological features supported the Myrtales as present in Vochysiaceae and the remaining one, inner integument with two layers of cells, was observed in some Qualea. Thus, the studied Vochysiaceae embryology conforms very well within the order and only their strongly monosymmetric and oligostemonous flowers are less common among Myrtales.

Further polyphyly of pinnotheroid crabs: the molecular phylogenetic position of the polychaete-associated Aphanodactylidae

2018 ◽  
Vol 32 (1) ◽  
pp. 92 ◽  
Author(s):  
Ling Ming Tsang ◽  
Shane T. Ahyong ◽  
Hsi-Te Shih ◽  
Peter K. L. Ng
Keyword(s):  
Marine Invertebrates ◽  
Histone H3 ◽  
Molecular Data ◽  
Phylogenetic Position ◽  
Monophyletic Origin ◽  
The Family ◽  
Molecular Phylogenetic ◽  
Nuclear Histone ◽  
Similar Body ◽  
High Degree

Pea crabs of the superfamily Pinnotheroidea De Haan, 1833 are known for their obligate commensal relationships with other marine invertebrates. The concomitant specialisations and adaptations of pinnotheroids have resulted in superficially similar body forms that include a high degree of structural reduction. This has confounded interpretation of their phylogenetic position in the Brachyura and interrelationships within Pinnotheroidea, though all were nevertheless believed to be united by a monophyletic origin of obligate commensalism. The family Aphanodactylidae Ahyong & Ng, 2009 was proposed for a group of genera associated with tube-dwelling polychaetes formerly classified in Pinnotheridae, and provisionally retained in the Pinnotheroidea. We investigated the phylogenetic position of Aphanodactylidae using molecular data from three markers (mitochondrial 12S and 16S rRNAs, and nuclear histone H3) covering five of the 12 described aphanodactylid species and a total of 15 thoracotreme families. We found Aphanodactylidae to be monophyletic, but widely distant from Pinnotheridae and instead most closely related to Macrophthalmidae (Ocypodoidea) and Varunidae (Grapsoidea). Therefore, the family Aphanodactylidae is corroborated, but its placement in Pinnotheroidea is rejected. Instead, the phylogenetic position of Aphanodactylidae, as clearly distant from other pinnotheroids, demonstrates that obligate commensalism has evolved independently multiple times within Thoracotremata.

Phylogenetic position of Coronastrum ellipsoideum and description of Parachlorella hussii sp. nov.

Biologia ◽  
2011 ◽  
Vol 66 (4) ◽  
Author(s):  
Christina Bock ◽  
Marie Pažoutová ◽  
Lothar Krienitz
Keyword(s):  
Molecular Data ◽  
Phylogenetic Position ◽  
Rrna Gene ◽  
Combined Approach ◽  
Molecular Analyses ◽  
Phylogenetic Studies ◽  
The Family ◽  
Its Rrna Gene ◽  
Molecular Phylogenetic ◽  
First Time

AbstractFollowing traditional morphological concepts, the genus Coronastrum is considered to be a rare member of the Scenedesmaceae (Chorophyceae). This classification may be called into question when molecular data are taken into account as well. Recent molecular phylogenetic studies revealed the polyphyletic origin of the family Scenedesmaceae within the Chlorophyceae and Trebouxiophyceae. In a combined approach of morphological analyses, SSU/ITS rRNA gene phylogeny and comparison of the ITS secondary structure, we analysed the systematics of Coronastrum strains available in public strain collections. Our molecular analyses revealed a new subclade within the Chlorella clade of the Chlorellaceae consisting of Coronastrum ellipsoideum, two strains with Dictyosphaerium-like morphology and one strain which fits the description of the genus Parachlorella. Four additional strains formed together a new lineage within the genus Parachlorella in the Parachlorella clade of the Chlorellaceae. These strains differ from the already known Parachlorella species in complementary base changes within the ITS2 and are here described for the first time as Parachlorella hussii sp. nov.

scholarly journals Gomphonella olivacea (Bacillariophyceae) – a new phylogenetic position for a well-known taxon, its typification, new species and combinations

2019 ◽  
Vol 152 (2) ◽  
pp. 219-247 ◽  
Author(s):  
Regine Jahn ◽  
Wolf-Henning Kusber ◽  
Oliver Skibbe ◽  
Jonas Zimmermann ◽  
Anh Tu Van ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
New Species ◽  
Molecular Data ◽  
Water Bodies ◽  
Phylogenetic Position ◽  
Lake Balaton ◽  
The Family ◽  
Clonal Cultures ◽  
German Waters ◽  
Scanning Electron

Background and aims – Within the project “German Barcode of Life – Diatoms” common diatoms of German waters were routinely isolated and cultivated. In order to understand the taxonomy and phylogeny of the genus Gomphonema, one of the most common taxa of Central Europe, known currently either under the name Gomphonema olivaceum in Europe or Gomphoneis olivacea in America, was studied. Methods – Twenty unialgal strains were established from five different water bodies in Germany and one from Lake Balaton, Hungary, which supplied molecular data (18S V4 and rbcL) besides morphometric and ultrastructural data. In addition, on eight populations from different water bodies including the type from Denmark, morphometric and micromorphological studies by light and scanning electron microscopy were performed. Key results – Molecular and micromorphological data show that the target taxon neither belongs to Gomphonema Ehrenb. nor to Gomphoneis Cleve. By reinstating the genus name Gomphonella Rabenh., the nomenclatural and taxonomic enigma of this taxon is solved, and with the presentation of the type by Hornemann the authorship of the epithet is clarified. Molecular data for the unialgal strains and several environmental clones show that there is more diversity in the Gomphonella olivacea clade than can be identified morphologically. In addition, the establishment of the new species Gomphonella coxiae and Gomphonella acsiae is supported. The molecular data classified Gomphonella species as belonging to the Cymbellales but not to the Gomphonemataceae. In addition, molecular data put Gomphoneis tegelensis R.Jahn & N.Abarca also into Gomphonella. In order to make the genera Gomphoneis and Gomphonema monophyletic, their astigmate members are transferred to Gomphonella. Conclusions – The results clarify that the gomphonemoid outline is not restricted to the family Gomphonemataceae but seem to be distributed across the entire order Cymbellales. This is shown in this paper for the revived genus Gomphonella, which contains the astigmate group of Gomphoneis and Gomphonema besides the longly disputed G. olivacea. Only a polyphasic approach, combining molecular and micromorphological data for taxonomy, nomenclatural evaluation, and observations from clonal cultures can reveal the full intricacies of evolutionary relations.

A new predatory leech from Vietnam (Hirudinida : Arhynchobdellida : Salifidae): its phylogenetic position with comments on the classification of the family

2015 ◽  
Vol 29 (5) ◽  
pp. 473 ◽  
Author(s):  
Takafumi Nakano ◽  
Son Truong Nguyen
Keyword(s):  
Phylogenetic Relationships ◽  
Phylogenetic Analyses ◽  
Morphological Characteristics ◽  
Molecular Data ◽  
Phylogenetic Position ◽  
12S Rrna ◽  
The Family ◽  
Morphological And Molecular Data ◽  
First Time

The family Salifidae is a predaceous leech taxon in the suborder Erpobdelliformes. Although Salifidae is widely distributed in the African, Oriental, Indo-Malayan, Sino-Japanese and Australasian regions, the phylogenetic relationships of the family Salifidae have never been tested using molecular data obtained from leeches collected from the family distributional range. A salifid species was collected for the first time in Vietnam, and relevant morphological and molecular data are presented here. Because the Vietnamese salifid species possesses unique morphological characteristics among the known salifid species, this species is herein described as a new species, Salifa motokawai, sp. nov. Phylogenetic analyses based on nuclear 18S rRNA and histone H3, as well as mitochondrial cytochrome c oxidase subunit I, tRNACys, tRNAMet, 12S rRNA, tRNAVal, 16S rRNA, tRNALeu and NADH dehydrogenase subunit 1 markers demonstrate that the Vietnamese salifid species is a close congener with the African Salifa perspicax and the Malagasy Linta be. Furthermore, molecular data revealed non-monophyly of the Asian salifid leeches. According to the observed phylogenetic relationships and morphological characteristics of the Vietnamese Salifa motokawai, sp. nov., the current classification of salifid taxa should be revised.

A new pygmy squid, Idiosepius hallami n. sp. (Cephalopoda: Idiosepiidae) from eastern Australia and elevation of the southern endemic ‘notoides’ clade to a new genus, Xipholeptos n. gen.

Zootaxa ◽  
2018 ◽  
Vol 4369 (4) ◽  
pp. 451
Author(s):  
AMANDA L. REID ◽  
JAN M. STRUGNELL
Keyword(s):  
New Genus ◽  
Sequence Divergence ◽  
Molecular Data ◽  
Phylogenetic Position ◽  
12S Rrna ◽  
Data Sets ◽  
Eastern Australia ◽  
The Family ◽  
Morphological Differences ◽  
Australasian Region

A new species of pygmy squid, Idiosepius hallami n. sp., is described from eastern Australia. It differs from I. notoides Berry, 1921 and I. pygmaeus Steenstrup, 1881 (also found in Australian waters) in a number of traits, including the number of club suckers, shape of the funnel-mantle locking apparatus and the modification of the male hectocotylus. Mitochondrial DNA markers (12S rRNA, 16S rRNA and cytochrome c oxidase subunit 1) indicate that it is also distinct on a molecular level. The new Australian species is also recognised as the taxon from Stradbroke I., Queensland for which the entire mitochondrial genome has been sequenced (Hall et al. 2014). Idiosepius hallami n. sp. is compared with all nominal Idiosepius Steenstrup, 1881 and a current summary of Idiosepius systematics is provided as a basis for future studies. Based on our analyses, we propose the elevation of the ‘notoides’ clade to the new genus Xipholeptos n. gen., retaining Idiosepius as the genetic epithet for all other nominal idiosepiids. This is supported by: monophyly of the two lineages based on molecular data sets, the level of sequence divergence between these lineages, and morphological differences. The ‘notoides’ clade is endemic to southern Australia and its basal phylogenetic position suggests that the family may have originated in the Australasian region. Idiosepiids are found in seagrass beds and among mangroves—among the most threatened ecosystems in the world. 

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