The comparative morphology, phylogeny and evolution of the gastropod family littorinidae

An account is given of the comparative morphology of the family Littorinidae, based on examination of 122 species, grouped into 32 subgenera. The shell, operculum and principal organ systems are described, and their phylogenetic significance assessed. A total of 53 characters, coded as 131 character states, were chosen for inclusion in a cladistic analysis of the phylogenetic relationships of the subgenera. This was performed by the program paup, using the principle of maximum parsimony. The outgroup for the analysis comprised representatives of the Pomatiasidae and Skeneopsidae. A consensus tree was obtained from cladograms with consistency indices of 0.408 (autapomorphies excluded).

Zootaxa ◽  
2009 ◽  
Vol 2022 (1) ◽  
pp. 1-14 ◽  
Author(s):  
RAFAEL LEMAITRE ◽  
PATSY A. MCLAUGHLIN ◽  
ULF SORHANNUS

Phylogenetic relationships within the “symmetrical” hermit crab family Pylochelidae were analyzed for 41 of the 45 species and subspecies currently considered valid. In the analyses, 78 morphological characters comprised the data matrix and the outgroup consisted of Thalassina anomala, a member of the Thalassinidae, and Munida quadrispina, a member of the Galatheidae. A poorly resolved strict consensus tree was obtained from a heuristic parsimony analysis of unweighted and unordered characters, which showed the family Pylochelidae and the subfamilies Pylochelinae and Pomatochelinae to be monophyletic taxa – the latter two groups had the highest Bremer support values. Additionally, while the subgenus Pylocheles (Pylocheles) was strongly supported, the subgenera Xylocheles, and Bathycheles were not. More fully resolved trees were obtained when using implied weighting, which recognized the monotypic subfamilies Parapylochelinae, Cancellochelinae and Mixtopagurinae. The subfamily Trizochelinae was found to have four distinct clades and several ambiguously placed taxa.


2005 ◽  
Vol 26 (2) ◽  
pp. 139-147 ◽  
Author(s):  
Francisca do Val ◽  
Paulo Nuin

AbstractThe systematics and phylogenetic relationships of the family Leptodactylidae are controversial as is the intrafamilial phylogeny of the leptodactylids. Here we analyze the relationships of the leptodactylid subfamily Hylodinae. This subfamily has been considered to be monophyletic and composed of three genera, Hylodes, Crossodactylus and Megaelosia. In the present study 49 characters were used, based on different studies on Leptodactylidae phylogeny. Maximum parsimony methods with unweighted and successively weighted characters were used to estimate the phylogeny of the Hylodinae. Upon analysis, the data provided further evidence of the monophyletic status of the three genera, with Megaelosia being the basal genus and the other two genera being sister taxa. The analysis with successive weighting results in a more resolved topology of the species subgroups of the genus Hylodes and separates this genus from Crossodactylus and confirms that the hylodines are monophyletic.


Zootaxa ◽  
2004 ◽  
Vol 760 (1) ◽  
pp. 1 ◽  
Author(s):  
LOURDES M.A. ELMOOR-LOUREIRO

The phylogenetic relationships among families of the Order Anomopoda (Crustacea, Branchiopoda, Cladocera) were investigated through a cladistic analysis including 93 characters and 37 terminal taxa (2 as outgroups). The strict consensus tree supported the monophyly of the Anomopoda and its families, and indicated the existence of two main clades: (Moinidae+Daphniidae) and (Dumontidae (Ilyocryptidae+Bosminidae+Radopoda)). The later clade was supported by trunk limb characters, probably related to life associated with the bottom or with macrophytes (lifestyle lost in Bosminidae, but still visible in some of its trunk limbs). Within the Radopoda, the Eurycercoidea was monophyletic, but the monophyly of the Macrothricoidea was not supported.


2002 ◽  
Vol 80 (11) ◽  
pp. 1887-1899 ◽  
Author(s):  
Alison M Murray ◽  
Kathlyn M Stewart

The family Alestidae (also referred to as the African Characidae) comprises the African dwarf forms ("Petersiini") and the genera Alestes, Brycinus, Bryconaethiops, and Hydrocynus. Although several authors have presented characters to support the monophyly of the family, a cladistic analysis of the group has not been published. Furthermore, the interrelationships of the constituent groups are the subject of some controversy. A cladistic analysis of the Alestidae is presented, including characters to support the monophyly of the family. The results of this study indicate that several species should be removed from the genus Brycinus, that Hydrocynus is the sister group of Alestes s.str. (containing only five species), and that the dwarf alestids ("Petersiini") do not form a monophyletic group.


1997 ◽  
Vol 75 (6) ◽  
pp. 963-970 ◽  
Author(s):  
André-Denis G. Wright ◽  
Denis H. Lynn

Phylogenetic relationships within the largest family of entodiniomorphid rumen ciliates, the Ophryoscolecidae, were inferred from comparisons of small-subunit ribosomal RNA gene sequences. These included three new sequences from Diplodinium dentatum (1638 base pairs (bp)), Eudiplodinium maggii (1637 bp), and Ophryoscolex purkynjei (1636 bp). Using morphological characters, Lubinsky constructed a cladogram of the Ophryoscolecidae, and on the basis of his analysis, he divided the family into three subfamilies (Entodiniinae, Diplodiniinae, Ophryoscolecinae) to reflect his "natural" groupings (G. Lubinsky. 1957. Can. J. Zool. 35: 141 – 159). Our cladistic analysis, based on the limited morphological and ultrastructural data available, indicates that there are no synapomorphies supporting the Diplodiniinae sensu Lubinsky. However, based upon the six 18S sequences for the Ophryoscolecidae, the rumen ciliates are monophyletic and fall into three distinct groups corresponding to Lubinsky's subfamilial division of the family. Our molecular analysis shows Entodinium to be the earliest branching rumen ciliate (subfamily Entodiniinae) and Eudiplodinium, not Diplodiium, branching first among the diplodiniines.


Zootaxa ◽  
2017 ◽  
Vol 4221 (1) ◽  
pp. 1 ◽  
Author(s):  
KANAMI OKU ◽  
HISASHI IMAMURA ◽  
MAMORU YABE

 Phylogenetic relationships of the family Cyclopteridae were reconstructed based on osteological and external characters.  The monophyly of the family was strongly supported by 47 commonly recognized synapomorphies, including six autapomorphies (plus one additional autapomorphy, presence of a dorsal process on the pelvis, recognized after the phylogenetic analysis) among the suborder Cottoidei.  As a result of the cladistic analysis, a single most parsimonious phylogeny was obtained, based on characters in 32 transformation series.  A new classification of Cyclopteridae based on reconstructed relationships, including three subfamilies [Liparopsinae, Cyclopterinae and Eumicrotreminae (newly established)] and four genera (Aptocyclus, Cyclopsis, Cyclopterus and Eumicrotremus), is proposed.    


2018 ◽  
Vol 11 ◽  
pp. 00021 ◽  
Author(s):  
Alexandr Kashin ◽  
Ivan Schanzer ◽  
Tatyana Kritskaya ◽  
Alena ParkhomenkO

The article examines the genetic diversity in 54 populations of 9 Chondrilla species (C. acantholepis, C. ambigua, C. brevirostris, C. canescens, C. graminea, C. juncea, C. laticoronata, C. latifolia, and C. pauciflora) in European Russia. Plastid DNA segments trnT–trnF are selected as markers. Reconstruction of evolutionary networks based on the principle of maximum parsimony reveals that the sample is divided into four groups, where group 1 is C. ambigua, 2 – C. brevirostris, 3 – C. laticoronata, 4 – C. acantholepis, C. canescens, C. graminea, C. juncea, and C. latifolia. The findings show that C. acantholepis, C. canescens, C. graminea, C. juncea and C. latifolia are to be treated as synonyms under the name of C. juncea.


2020 ◽  
Vol 96 (2) ◽  
pp. 637-637
Author(s):  
Karla D. A. Soares ◽  
Marcelo R. de Carvalho

The genus Scyliorhinus is part of the family Scyliorhinidae, the most diverse family of sharks and of the subfamily Scyliorhininae along with Cephaloscyllium and Poroderma. This study reviews the phylogenetic relationships of species of Scyliorhinus in the subfamily Scyliorhininae. Specimens of all Scyliorhinus species were examined as well as specimens of four of the 18 species of Cephaloscyllium, two species of Poroderma, representatives of almost all other catshark (scyliorhinid) genera and one proscylliid (Proscyllium habereri). A detailed morphological study, including external and internal morphology, morphometry and meristic data, was performed. From this study, a total of 84 morphological characters were compiled into a data matrix. Parsimony analysis was employed to generate hypotheses of phylogenetic relationships using the TNT 1.1. Proscyllium habereri was used to root the cladogram. The phylogenetic analysis, based on implied weighting (k = 3; 300 replications and 100 trees saved per replication), resulted in three equally most parsimonious cladograms with 233 steps, with a CI of 0.37 and an RI of 0.69. The monophyly of the subfamily Scyliorhininae is supported as well as of the genus Scyliorhinus, which is proposed to be the sister group of Cephaloscyllium. The phylogenetic relationships amongst Scyliorhinus species are presented for the frst time.


Zootaxa ◽  
2007 ◽  
Vol 1401 (1) ◽  
pp. 33 ◽  
Author(s):  
REBECCA L. HUNTER

A phylogenetic analysis using morphological characters was done on the Antarctic ophiuroid genus Ophiurolepis Matsumoto, 1915. This genus is one of the more abundant and ecologically dominant ophiuroid genera in the Antarctic and surrounding Southern Ocean. Maximum parsimony was used to infer phylogenetic relationships. Although strongly supported nodes were not recovered for most groupings within Ophiurolepis, this first attempt at a phylogeny revealed the presence of three tentative clades. Two of the three Ophiurolepis clades included species currently assigned to other genera, but closely allied with Ophiurolepis in the taxonomic literature. This indicates that Ophiurolepis as currently defined is not a monophyletic group. Additional forms of data, namely molecular, are needed to more definitively resolve relationships within this group.


2018 ◽  
Vol 18 (4) ◽  
Author(s):  
Gustavo Darlim ◽  
Manoela M. F. Marinho

Abstract Cladistic analysis of fishes are mostly based on osteological studies. Phylogenetic relationships within the family Characidae are poorly known in part due to the lack of anatomical studies of its members, including osteology. The present contribution aims to offer a detailed description of all bony complexes of Moenkhausia lepidura. Two remarkable morphological conditions present in the species are discussed: a bony lamella on the proximal portion of the ribs and a basal expansion of the gill rakers. A morphological survey of several species of Characidae along with available phylogenetic information of the family indicates the putative relationships of Moenkhausia lepidura with other small characids presenting bony lamella on ribs and a dark mark on the caudal fin.


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