scholarly journals Evolution in the Model Genus Antirrhinum Based on Phylogenomics of Topotypic Material

2021 ◽  
Vol 12 ◽  
Author(s):  
Ana Otero ◽  
Mario Fernández-Mazuecos ◽  
Pablo Vargas

Researchers in phylogenetic systematics typically choose a few individual representatives of every species for sequencing based on convenience (neighboring populations, herbarium specimens, samples provided by experts, garden plants). However, few studies are based on original material, type material or topotypic material (living specimens from the locality where the type material was collected). The use of type or topotypic material in phylogenetic studies is paramount particularly when taxonomy is complex, such as that of Antirrhinum (Plantaginaceae). In this paper, we used topotypic materials of Antirrhinum at the species level (34 species proposed by previous authors), 87 specimens representing the species distributions and >50,000 informative nucleotide characters (from ∼4,000 loci) generated by the genotyping-by-sequencing (GBS) technique: (i) to test two explicit taxonomic hypotheses widely followed by local taxonomic treatments; (ii) to robustly estimate phylogenetic relationships; (iii) to investigate the evolution of key morphological characters and biogeographic centers of differentiation. Two GBS phylogenies based on two datasets (87 localities and 34 topotypic specimens) revealed that: (1) Sutton’s (1988) taxonomic account is the most congruent with phylogenetic results, whereas division of Antirrhinum into three major clades disagrees with Rothmaler’s (1956) infrageneric classification; (2) monophyly of populations currently included in the same species is primarily supported; (3) the historically recognized Antirrhinum majus group is not monophyletic; (4) sister-group relationships are robust for eight species pairs; (5) the evolutionary radiation of 26 species since the Pliocene is underpinned given a high rate of diversification (0.54 spp. Myr–1); (6) a geographic pattern of speciation is reconstructed, with northern Iberia as the center of early diversification followed by more recent speciation in southeastern Iberia; and (7) multiple acquisitions of key taxonomic characters in the course of Antirrhinum diversification are strongly supported, with no evidence of hybridization between major clades. Our results also suggest incipient speciation in some geographic areas and point to future avenues of research in evolution and systematics of Antirrhinum.

Phytotaxa ◽  
2021 ◽  
Vol 498 (2) ◽  
pp. 87-103
Author(s):  
YOU-PAI ZENG ◽  
QIONG YUAN ◽  
QIN-ER YANG

Based on critical observations on herbarium specimens (including type material) and living plants in the wild from its type locality, we demonstrate that Thalictrum kangdingense, recently described from Kangding county in western Sichuan province, China, is readily distinguishable from T. xinningense by an array of morphological characters but is actually conspecific with T. megalostigma, a species with its type locality also in Kangding. We therefore reduce T. kangdingense to the synonymy of T. megalostigma herein. The morphological distinction between T. baicalense and T. megalostigma is also clarified.


2018 ◽  
Vol 93 (2) ◽  
pp. 208-219
Author(s):  
J.F. Santos Neto ◽  
N.G.S. Costa ◽  
G.B. Soares ◽  
M.V. Domingues

AbstractTwo new species of Diaphorocleidus and one new species of Rhinoxenoides n. gen. are described from the gills of Acestrorhynchus falcatus (Bloch) from rivers of north-eastern Pará, Brazil. Diaphorocleidus jaymedeloyolai n. sp. is characterized by a male copulatory organ (MCO) possessing three counterclockwise coils; similar anchors with subtriangular superficial roots; a ventral bar with posteromedial projection; and hooks of pairs 1, 4 and 7 approximately three times longer than hook pair 5. Diaphorocleidus sclerocolpus n. sp. differs from its congeners by a dual-branched accessory piece articulated with the MCO and a sclerotized tubular vagina with a bottle-shaped vestibule. Rhinoxenoides n. gen. is proposed and is characterized by possessing: MCO sclerotized with clockwise coils; an accessory piece articulated to the base of MCO; a sinistroventral vaginal aperture; ventral anchor with conspicuous roots; dorsal anchor with superficial root five times longer than deep root; and absence of dorsal bar. The proposal of Rhinoxenoides n. gen. is also supported by its phylogenetic relationship with Protorhinoxenus prochilodi and species of Rhinoxenus, using 16 morphological characters, which resulted in the following hypothesis of sister-group relationships: Rhinoxenoides n. gen. [Protorhinoxenus (Rhinoxenus curimatae (R. nyttus (R. bulbovaginatus (R. guianensis, R. piranhus, R. euryxenus (R. arietinus, R. anaclaudiae)))))].


2012 ◽  
Vol 46 (6) ◽  
pp. 31-48
Author(s):  
K. B. Sukhomlin

Abstract Phylogenetic relationships among the Palaearctic genera of the subfamily Simuliinae are analyzed based on the matrix of 100 morphological characters and 37 taxa, including 6 outgroups. Parsimonic analysis was resulted in 3 consensus trees (weighting based on CI, RI and RC indices) of slightly different topology, which show monophyly of the subfamily Simuliinae, tribes Stegopternini, Nevermanniini, Wilhelmiini and Simuliini, and a possible sister-group relationships between the latter two tribes. Tribe Ectemniini is apparently a paraphyletic formation. The analysis also supports transferring of the Stegopternini and Nevermanniini from Prosimuliinae to Simuliinae.


2016 ◽  
Vol 149 (1) ◽  
pp. 8-25 ◽  
Author(s):  
Bjarte H. Jordal ◽  
Johanna Kaidel

AbstractMicracidini (Coleoptera: Curculionidae: Scolytinae) is an unusual tribe of mainly bigynous bark beetles found in dry forests and scrublands in Afrotropical and Neotropical regions. Their phylogenetic relationship to other bark beetle groups is poorly known with few clues from external morphology. Hence, a phylogenetic analysis of five genes (COI, EF-1a, 28S, CAD, ArgK) and morphological (internal and external) data was conducted to test potential sister group relationships, including 56 outgroup genera in 22 tribes, and 18 species in 10 genera of Micracidini.CactopinusSchwarz – a genus with many cactus feeding species – was nested within a clade of all Neotropical and Nearctic genera. The New World was colonised by an Afrotropical ancestor about 75–85 million years ago, where cactus feeding inCactopinusevolved much later. All analyses indicated a paraphyletic clade of Afrotropical micracidines, strongly supporting inclusion of the Ipini genusDendrochilusSchedl inAfromicracisSchedl. Hypoborini appear to be one of the more plausible sistergroup candidates to Micracidini, and revealed morphological similarity in protibial and proventricular characters. Most phylogenetic results were supported independently by morphological and molecular data and therefore document the power of thorough examination of morphological characters analysed properly in a phylogenetic context.


2006 ◽  
Vol 20 (5) ◽  
pp. 503 ◽  
Author(s):  
Gregory D. Edgecombe ◽  
Gonzalo Giribet

Scutigeromorpha (‘house centipedes’) play a pivotal role in myriapod systematics in being the sister group to all other chilopods, but their internal phylogeny has not been comprehensively appraised since K. W. Verhoeff’s morphological investigations a century ago. Relationships between the three families of Scutigeromorpha are inferred based on a combined analysis of approximately 5.5 Kb of sequence data from five molecular markers (complete 18S rRNA, a 2.2-Kb fragment of 28S rRNA, 16S rRNA, cytochrome c oxidase subunit I, histone H3) and 33 ingroup morphological characters. Molecular data are available for 19 ingroup terminals representing 14 morphospecies that include the genera Scutigerina, Madagassophora (family Scutigerinidae), Sphendononema (family Pselliodidae), Scutigera, Thereuopoda, Thereuopodina, Thereuonema, Allothereua and Parascutigera (family Scutigeridae). Morphology resolves the southern African–Malagasy Scutigerinidae as sister to all other Scutigeromorpha, whereas rival sister-group relationships between the Neotropical–Afrotropical Pselliodidae and Scutigerinidae + Scutigeridae or Pselliodidae + Scutigerinidae and Scutigeridae are resolved by the molecular and combined analyses. Monophyly of Scutigeridae and Thereuoneminae are stable across a broad range of analytical parameters. Thereuoneminae is composed of two stable clades: an Allothereua + Parascutigera group, and a grouping of Thereuopoda, Thereuonema and Thereuopodina. Molecular and combined analyses resolve the genus Scutigerina and the morphospecies Scutigerina weberi as paraphyletic, in both cases with a Malagasy clade excluding populations from southern Africa.


2010 ◽  
Vol 85 (4) ◽  
pp. 353-380 ◽  
Author(s):  
M.V. Domingues ◽  
F.P.L Marques

AbstractThe marine-derived stingrays of Potamotrygonidae, endemic to South American river systems, host an interesting parasite fauna equally related to marine lineages. Among those lineages, the diversity and phylogenetic relationships within Potamotrygonocotyle – a monocotylid monogenoidean specific to potamotrygonids – are poorly known, since 9 of 10 species attributed to this genus have been described in the past 3 years. Here, we readdress the diversity of Potamotrygonocotyle after examining the gills of 436 potamotrygonid individuals representing 12 described and 14 potentially undescribed species of freshwater stingrays from 19 major river systems of South America (i.e. sub-basins). We recognized 12 valid species within the parasite genus, of which four are described in this study. Our taxonomic decisions were based on the phylogenetic analysis of 14 ingroup terminal taxa and 12 morphological characters, which resulted in the following hypothesis of sister-group relationships: ((P. dromedarius, P. tatianae sp. nov.), (P. rionegrense, P. auriculocotyle sp. nov., ((P. quadracotyle, P. umbella), (P. septemcotyle sp. nov., (P. chisholmae, P. uruguayense)), (P. tsalickisi, P. eurypotamoxenus, P. rarum, (P. tocantinsense sp. nov., P. aramasae))))). According to our hypothesis, the absence of autapomorphic features for some nominal species, and the re-evaluation of morphological variation among populations, led us to consider P. eurypotamoxenus and P. uruguayense as junior synonymys of P. tsalicksi and P. chisholmae, respectively. Finally, we address the importance of biogeographic and host representation, in order to fully understand the patterns of morphological variation and host specificity within this group. We found that hypotheses of species delimitation depend greatly on efforts to sample specimens throughout its distributional range and that host specificity within this genus varies dramatically among lineages.


Zootaxa ◽  
2011 ◽  
Vol 2965 (1) ◽  
pp. 1
Author(s):  
ISABELLE M. VEA

The monotypic genus Chlamydolecanium Goux (Hemiptera: Coccoidea: Coccidae) is known only from the original collection in Corsica. The original description does not allow definite placement in any of the subfamilies in the Coccidae. Although it had been suggested that it belonged to the Cardiococcinae, no other members of this subfamily were geographically close. The adult female and 1 st -instar nymph of the type species, Chlamydolecanium conchioides Goux are here redescribed. A parsimony analysis was undertaken based on 56 morphological characters of the adult females in 29 taxa (24 genera considered to belong to the Cardiococcinae, plus Parafairmaria bipartita (Signoret), an incertae sedis monospecific genus possibly close to Cardiococcinae, plus the recently described Kenima galilit Ben-Dov plus two other soft scale genera as outgroups (Coccus hesperidum L. and Paralecanium frenchii (Maskell)). This analysis confirmed the placement of the genus Chlamydolecanium within the Cardiococcinae clade, although its sister-group relationships remain unresolved. Its geographic distribution and taxonomic relationships are discussed.


Phytotaxa ◽  
2021 ◽  
Vol 511 (3) ◽  
Author(s):  
YOU-PAI ZENG ◽  
QIONG YUAN ◽  
QIN-ER YANG

Based on critical observations on both herbarium specimens (including type material) and living plants in the wild, here we clarify some morphological characters in the Chinese species Thalictrum przewalskii (Ranunculaceae) and demonstrate that T. lasiogynum and T. latistylum, described respectively from China’s Sichuan and Gansu provinces, are conspecific with it. We therefore reduce T. lasiogynum and T. latistylum to the synonymy of T. przewalskii. Thalictrum sect. Platystylus, which was established to accommodate T. latistylum, is reduced to the synonymy under T. sect. Omalophysa. The identity of T. rockii is further confirmed and the distribution in China of T. sparsiflorum, a species most closely similar to T. przewalskii and widely distributed in northeastern Asia and North America, is also determined.


Phytotaxa ◽  
2014 ◽  
Vol 167 (1) ◽  
pp. 133 ◽  
Author(s):  
ZOLTÁN BARINA ◽  
GERGELY KIRÁLY

Pyrus magyarica was considered as a “superendemic” species of the Carpathian Basin for a long time; however, despite its presumed significance, doubts about its taxonomical status have been raised. The confusions originate from the invalidity of the description and the lack of type material. Latter interpretations are not consistent and contradict the description of the species in the protologue. The authors attempted to get access to the original material of the taxon, but no vouchers or living specimens that correspond to the protologue were found; herbarium specimens assigned as P. magyarica mostly refer to P. pyraster. Based on the available records, P. magyarica cannot be clearly defined and re-described; thus we propose to leave off the use of the name P. magyarica as it has no clear content.


1987 ◽  
Vol 65 (9) ◽  
pp. 2292-2310 ◽  
Author(s):  
Hugh Griffith

A cladogram indicating sister-group relationships within the pinnotherid crab genus Dissodactylus is constructed from analysis of 28 morphological characters. The outgroup method was used to determine character polarities. Parapinnixa and Sakaina are shown to be a monophyletic group, and are suggested to be the sister group of Dissodactylus. Within Dissodactylus, two mutually exclusive, monophyletic subgroups are found, one containing nine, the other four species. Both of these groups include Atlantic and Pacific representatives. Two Atlantic–Pacific species pairs are suggested to be sister species (D. mellitae–D. glasselli and D. primitivus–D. schmitti). Members of the group of nine species are inhabitants primarily of mellitid sand dollars, although one species, D. primitivus, is a symbiont of heart urchins (Spatangoida). Members of the group of four species are inhabitants of sea biscuits of the genus Clypeaster (Clypeasteridae). An evolutionary scenario is presented, which suggests that a free-living ancestor colonized mellitid sand dollars, and subsequent specializations led to the colonizations of the genus Clypeaster and genera of Spatangoida.


Sign in / Sign up

Export Citation Format

Share Document