Morphometrical and genetic comparison of two nematode species: H. spumosa and H. dahomensis (Nematoda, Heterakidae)

2013 ◽  
Vol 58 (3) ◽  
Author(s):  
Alexis Ribas ◽  
Jöelle Bellocq ◽  
Albert Ros ◽  
Papa Ndiaye ◽  
Jordi Miquel

AbstractHeterakis is a genus of parasitic nematodes, the majority of which are found in ground-feeding birds and only rarely in mammals. The best-known species is Heterakis spumosa, a parasite associated with the cosmopolitan invasive rodent Rattus rattus of Asiatic origin. Heterakis dahomensis was described in 1911 as a parasite of the Gambian giant rat (Cricetomys gambianus) from Benin (Africa), subsequently synonymized to H. spumosa by Hall (1916). The study of helminths in African rodents is scarce and patchy. Since the original description of H. dahomensis, there have been only a few reports from Africa of species belonging to the genus Heterakis and the validity of this species has never in fact been confirmed or rejected. In the present study individual Heterakis spp. were collected from C. gambianus from Senegal. The morphological data taken point to differences between Heterakis dahomensis and H. spumosa, specifically in the number of tail papillae in males and in the vulva cuticular processes of females. In addition, molecular data revealed differences between these taxa and so H. dahomensis should be considered as a valid species. Moreover, recent changes in the systematics of the genus Cricetomys mean that it is now necessary to study the morphology and genetics of the Heterakis specimens collected from Cricetomys spp. (previously assigned to C. gambianus) in order to determine their taxonomic status as either H. dahomensis o H. spumosa.

Zootaxa ◽  
2020 ◽  
Vol 4778 (2) ◽  
pp. 343-356
Author(s):  
FISAYO Y. DARAMOLA ◽  
SAMUEL B. ORISAJO ◽  
ANTOINETTE P. MALAN ◽  
MARIETTE MARAIS

The genus Helicotylenchus contains cosmopolitan, ubiquitous plant-parasitic nematodes with some species capable of causing significant economic damage to agricultural crops. Accurate species identification in this genus is essential in recognizing the damaging species and establishing effective management options. In a study on cocoa plantations in Nigeria, two species of spiral nematodes were found in high numbers from soil samples obtained from a six-decade old cocoa plantation at the Cocoa Research Institute of Nigeria. An integrated approach involving a combination of morphology, morphometrics, and molecular tools was used to identify the nematode species. Morphological data indicate the presence of both H. multicinctus and H. dihystera. There is congruence in the morphological and molecular data obtained for H. multicinctus. However, phylogenetic analysis of the 28S rDNA expansion segment revealed a high variability in the sequences of the Nigerian population of H. dihystera, suggesting the need for a careful appraisal and more comparative studies. 


Phytotaxa ◽  
2017 ◽  
Vol 299 (2) ◽  
pp. 151
Author(s):  
MARYAM BEHROOZIAN ◽  
JAMIL VAEZI ◽  
MOHAMMAD REZA JOHARCHI ◽  
FARSHID MEMARIANI

The genus Linum consists of 15 species in Iran. A new species as well as a new record from Iran is described and illustrated here as L. khorassanicum and L. turcomanicum, respectively. The original description of the latter species is incomplete and ambiguous, probably due to incomplete taxon sampling. In this work, after a comprehensive taxon sampling from the entire distribution range of the species in northeast of Iran, the taxonomic description of L. turcomanicum is completed. The present study considers morphological and molecular (the nrITS region) analyses of the both species. In phylogenetic analysis based on the molecular data, we included these species and some related Linum species to examine the phylogenetic relationship of the new species and L. turcomanicum with other members of the genus. Linum turcomanicum is morphologically almost similar to L. austriacum and L. perenne, but it can be distinguished from them on the basis of several traits such as fruiting-pedicel form and length of petal. Likewise, results obtained from the molecular phylogenetic tree are consistent with those obtained from the morphological data. Linum khorassanicum is well characterized morphologically by having erect fruiting pedicels and inflorescence with few flowers. Our results suggest that the morphological data are in agreement with the molecular phylogenetic tree in which the taxonomic status of L. khorassanicum is confirmed as a new species. Based on IUCN Red List categories and criteria, L. khorassanicum and L. turcomanicum are evaluated as Endangered and Near Threatened species, respectively. 


Author(s):  
Antonio Zurita ◽  
Cristina Cutillas

AbstractCtenophthalmus is considered the largest genus within the Order Siphonaptera. From a morphological point of view, only males of this genus can be identified at species and subspecies levels using morphological keys, whereas there are no morphological criteria in order to classify females at these taxonomical levels. Furthermore, the amount of available molecular and phylogenetic data for this genus is quite scarce so far. The main objective of this work was to assess the utility of the combination of nuclear and mitochondrial markers with respect to their ability to differentiate among different subspecies within the Ctenophthalmus genus. With this purpose, we carried out a comparative morphological and molecular study of three different subspecies (Ctenophthalmus baeticus arvernus, Ctenophthalmus nobilis dobyi, and Ctenophthalmus andorrensis catalaniensis) in order to clarify and discuss its taxonomic status. In addition, our study complemented the molecular data previously provided for Ctenophthalmus baeticus boisseauorum and Ctenophthalmus apertus allani subspecies. We sequenced five different molecular markers: EF1-α, ITS1, ITS2, cox1, and cytb. Our results confirmed that morphological data by themselves are not able to discriminate among Ctenophthalmus female taxa; however, the combination of the nuclear marker EF1-α together with mtDNA markers cytb and cox1 constituted a useful taxonomical and phylogenetic tool to solve this issue. Based on these results, we consider that the use of this molecular approach should be gradually used within Ctenophthalmus genus in order to complement its classical taxonomy and clarifying the complex taxonomy of other congeneric species of fleas.


Zootaxa ◽  
2018 ◽  
Vol 4512 (1) ◽  
pp. 1
Author(s):  
CHRISTINE M. KAISER ◽  
HINRICH KAISER ◽  
MARK O’SHEA

Since its conceptualization in 1854, 29 species of the colubrid genus Stegonotus have been recognized or described, of which 15 (admiraltiensis, batjanensis, borneensis, cucullatus, derooijae, diehli, florensis, guentheri, iridis, heterurus, melanolabiatus, modestus, muelleri, parvus, poechi) are still considered valid today. Original species descriptions for the members of this genus were published in Dutch, English, French, German, and Italian and, perhaps as a consequence of these polyglot origins, there has been a considerable amount of confusion over which species names should be applied to which populations of Stegonotus throughout its range across Borneo, the Philippines, Wallacea, New Guinea, Australia, and associated archipelagos. In addition, the terminology used to notate characteristics in the descriptions of these forms was not uniform and may have added to the taxonomic confusion. In this paper, we trace in detail the history of the type specimens, the species, and the synonyms currently associated with the genus Stegonotus and provide a basic, species-specific listing of their characteristics, derived from our examination of over 1500 museum specimens. Based on our data, we are able to limit the distribution of S. modestus to the islands of Ambon, Buru, and Seram in the central Moluccas of Indonesian Wallacea. We correct the type locality of S. cucullatus to the Manokwari area on the Bird’s Head Peninsula of West Papua, Indonesian New Guinea and designate a neotype for S. parvus, a species likely to be a regional endemic in the Schouten Archipelago of Cenderawasih Bay (formerly Geelvink Bay), Indonesian New Guinea. We unequivocally identify and explain the problematic localities of the type specimens of S. muelleri and Lycodon muelleri, which currently reside in the same specimen jar. We remove L. aruensis and L. lividum from the synonymy of S. modestus and recognize them as S. aruensis n. comb. and S. lividus n. comb., respectively. We remove S. keyensis and Zamenophis australis from the synonymy of S. cucullatus and recognize them as S. keyensis n. comb. and S. australis n. comb., respectively. We further remove S. reticulatus from the synonymy of S. cucullatus, S. dorsalis from the synonymy of S. diehli, and S. sutteri from the synonymy of S. florensis. We designate lectotypes for S. guentheri, S. heterurus, S. lividus, and S. reticulatus. Lastly, we introduce S. poechi, a valid species not mentioned in the scientific literature since its description in 1924. This brings the diversity in the genus Stegonotus to 22 species. We also caution that in a complex group of organisms like Stegonotus any rush to taxonomic judgment on the basis of molecular and incomplete morphological data sets may perpetuate errors and introduce incongruities. Only through the careful work of connecting type material with museum specimens and molecular data can the taxonomy and nomenclature of complex taxa be stabilized. 


2021 ◽  
Author(s):  
Louis Nastasi ◽  
Andrew Deans

Cynipidae (Hymenoptera: Cynipoidea) is a diverse group of wasps, many of which are capable of inducing plants to make novel structures, galls, that protect and nourish the wasps' larvae. Other cynipids, especially those species in Ceroptresini and Synergini, are understood to be usurpers of galls made by other cynipids. The North American cynipid fauna has not been fully cataloged since 1979, but there is renewed interest in revising the taxonomy and in doing research that sheds light on the mechanisms of gall induction, the evolution of this life history, and their ecological interactions more broadly. Significant taxonomic changes have impacted the group since 1979, thereby warranting a new catalog. The current state of knowledge of species classified in Aulacideini, Ceroptresini, Diastrophini, Diplolepidini, Phanacidini, and Synergini in the United States, Canada, and Mexico is summarized in catalog format. We report 323 names, including 170 valid species of rose gall wasps, herb gall wasps, and inquiline gall wasps, classified in 12 genera, from the United States, Canada, and Mexico. Current taxonomic status, distribution, host associations, and vernacular names are listed for each species. The catalog also includes the original description of galls for many species of gall-inducer, as well as atomized characterizations of different gall traits as key-value pairs. For most galling species without existing vernacular names, new vernacular names are proposed.


2018 ◽  
Vol 3 (4) ◽  
pp. 14-28 ◽  
Author(s):  
I. P. Bondarev

The name Flexopecten glaber ponticus (Bucquoy, Dautzenberg & Dollfus, 1889) is generally used for the only Pectinidae representative inhabiting the Black Sea. It is registered in the Red Book of the Republic of Crimea as endemic subspecies reducing in amount. F. glaber ponticus is listed in WoRMS MolluscaBase as the only accepted subspecies of Flexopecten glaber (Linnaeus, 1758). In the past its taxonomic status has been changed from a geographic variety to valid species. The purpose of this study is to establish its correct taxonomic status. The study is based on a comparative analysis of conchological features of Flexopecten glaber and F. glaber ponticus in relation with the brief natural history of population in the Black Sea. Sampling was performed by snorkel equipment in Kazach’ya Bay (Black Sea, Crimea, Sevastopol) at 2–6 m depths. A total of 100 scallop specimens were sampled in September 2017. To assure a better understanding in a broader context those results are compared with the previously published morphological data based on the analysis of a large amount of material from the Black Sea and the Mediterranean Sea – Marmara Sea regions. Comparative analysis of conchological features of F. glaber ponticus from the Black Sea with F. glaber from the Mediterranean region has not revealed any distinct differences between them. Thus, there are no evidenced data for the diagnosis of F. glaber ponticus as a subspecies. Species F. glaber appeared in the Black Sea not earlier than 7,000 years ago and formed a well developed population less than 3,000 years ago. We have to conclude that the specified divergence period is not long enough to form a subspecies. As a result of the present survey the subspecific status of F. glaber ponticus is not retained and the name is placed in synonymy of the parent species Flexopecten glaber.


ZooKeys ◽  
2015 ◽  
Vol 489 ◽  
pp. 1-13 ◽  
Author(s):  
Gezahegne Damessa ◽  
Wim Bert ◽  
Frieda Decraemer

A total of six soil samples were collected around rhizosphere of citrus plants during 2010 from Melkassa Agricultural Research Center experimental station, Ethiopia. From these samples two most important ecto-plant parasitic nematodes of the genus Xiphinema were found and analysed. The genus Xiphinema is a large group of the phylum nematoda which constitutes more than 260 species. They are polyphagous root- ectoparasites of many crop plants and some species of this genus cause damage by direct feeding on root tips and transmit nepoviruses. The delimitation and discrimination of two species in the genus is presented, described herein as Xiphinemaelongatum and Xiphinemapachtaicum. Morphological and morphometric data were done using light microscopy and results of both species were fit within the previously described nematode species of Xiphinemaelongatum and Xiphinemapachtaicum. 18S rDNA were analysed using Bayesian inference (BI) method to reconstruct phylogenetic relationships of the studied Xiphinema sp. (KP407872Xiphinemaelongatum and KP407873Xiphinemapachtaicum) with other Xiphinema species. The 18S rDNA sequence of Xiphinemapachtaicum was alike to previously described species from the GenBank but Xiphinemaelongatum exhibited very small levels of nucleotides differences (0.4%) which might be possible intra-specific divergence. Though this region of rDNA has less resolution on complex species, its combination with morphological and morphometric analyses, suggests these species as Xiphinemaelongatum and Xiphinemapachtaicum with the GenBank accession number of KP407872 and KP407873, respectively. Short notes, morphological measurements, illustrations, and molecular data are given to these species. These species are reported for the first time from Ethiopia and it provides new geographical information of these organisms.


2019 ◽  
Vol 40 (4) ◽  
pp. 511-521
Author(s):  
Luana Rodrigues Lima ◽  
Marcos Jorge Matias Dubeux ◽  
Filipe Augusto Cavalcanti do Nascimento ◽  
Daniel Pacheco Bruschi ◽  
Tamí Mott

Abstract Boana atlantica was described based on morphological characters to acommodate populations from Bahia state, Brazil, previously referred to as B. punctata. However, its taxonomic validity is questionable due to inconsistencies in bioacoustic data. Here, we integrate molecular, cytogenetic and morphological data to re-evaluate the taxonomic status of B. atlantica. Molecular analyses provided strong support for the hypothesis that B. atlantica is a valid species, being, however, nominal populations from Bahia state paraphyletic with respect to individuals of B. atlantica collected in Alagoas and Pernambuco states. These populations shown high genetic divergence in the 16S rRNA mitochondrial fragment, and we consider populations from Alagoas and Pernambuco as a putative new candidate species of Boana punctata group. The external and internal morphology of the tadpoles of these lineages were similar, but Nucleolar Organizer Regions (NOR) was sited in different chromosomes. Our results indicate that B. atlantica is paraphyletic and may be a complex of species. Morphological of adult and/or bioacoustical data should be further assessed to find diagnostic characters to tease these lineages apart and name them properly.


2005 ◽  
Vol 19 (4) ◽  
pp. 297 ◽  
Author(s):  
Peter J. Schwendinger ◽  
Gonzalo Giribet

The hitherto monotypic opilionid genus Fangensis Rambla, 1994 is re-evaluated from new material collected in northern, western and southern Thailand. The original description of F. leclerci Rambla (type material not traceable) was based on specimens belonging to at least three distinct species. Fangensis leclerci is thus redefined and the binomen restricted to specimens from a cave in northern Thailand only. Three new species are described, F. spelaeus, sp. nov. and F. cavernarus, sp. nov. from two caves in western Thailand and F. insulanus, sp. nov. from forests on two islands in southern Thailand. Taxonomic characters are discussed and relationships among Fangensis species and between Fangensis and other cyphophthalmids are evaluated using morphological data and ~4 Kb of molecular data from three loci, two nuclear ribosomal genes and a mitochondrial coding gene. Overall, data indicate monophyly of Stylocellidae and morphological and ribosomal data suggest monophyly of Fangensis, which is in turn divided into two clades, one composed of the three species from northern and western Thailand and the other represented by the species from southern Thailand. Observations on mating in F. leclerci are provided.


Zootaxa ◽  
2007 ◽  
Vol 1517 (1) ◽  
pp. 53-62 ◽  
Author(s):  
FRANK GLAW ◽  
ZOLTÁN T. NAGY ◽  
MIGUEL VENCES

Based on a specimen found at Montagne d'Ambre in northern Madagascar morphologically agreeing with Compsophis albiventris Mocquard, 1894, we report on the rediscovery of this enigmatic snake genus and species and its molecular phylogenetic relationships. Compsophis albiventris, considered to be the only representative of its genus and unreported since its original description, bears strong morphological similarities to species of Geodipsas Boulenger, 1896. A molecular phylogeny based on DNA sequences of three mitochondrial and nuclear genes (complete cytochrome b, fragments of 16S rRNA and c-mos) in Compsophis albiventris and three Geodipsas species corroborated close relationships between C. albiventris and Geodipsas boulengeri, and showed that the genera Compsophis and Geodipsas together form a monophyletic unit. Despite the general similarities, morphological data and chromatic features support the existence of two species groups, corresponding to Compsophis and Geodipsas. We consequently consider Geodipsas as a subgenus of Compsophis and transfer all species currently in Geodipsas into the genus Compsophis.


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