scholarly journals Assessing the molecular diversity of Hildaea (Poaceae, Panicoideae): reaching a compromise between the splitter and the lumper

2019 ◽  
Vol 192 (1) ◽  
pp. 121-147
Author(s):  
Christian Silva ◽  
Cristiane Snak ◽  
Gerrit Davidse ◽  
Cássio Van Den Berg ◽  
R Patrícia Oliveira

Abstract The taxonomy of some groups of plants is challenging, and the strict use of morphological characters may not be enough to solve problems of species delimitation. Hildaea, a genus of tropical grasses recently segregated from Ichnanthus section Foveolatus, is mostly composed of species with obscure boundaries. This group was revised by two authors, Rogers and Stieber, with distinct opinions. The former recognized > 30 taxa, whereas the latter reduced this number to six. In the present study, we re-evaluate current and previous classifications through a comprehensively sampled phylogenetic analysis using plastid (ndhF) and nuclear data (ETS and ITS). Our results demonstrate that the diversity in Hildaea is a middle ground between the splitter and the lumper, indicating that several taxa currently treated as synonyms should be reinstated. Old World Hildaea were found to belong to two clades, one including species from Asia and Oceania, and another including species from the Neotropics and from western Africa. Topological incongruences suggest that hybridization may be a possible cause for the morphological variation observed and also an important evolutionary driver.

Zootaxa ◽  
2017 ◽  
Vol 4320 (3) ◽  
pp. 505 ◽  
Author(s):  
ROMANA KALOUSOVA ◽  
LADISLAV BOCAK

Cladophorus Guérin-Méneville, 1830 are endemic Papuan net-winged beetles which take part in highly diverse Müllerian mimicry rings. Available specimens were sequenced for cox1–tRNA-Leu–cox2 mitochondrial DNA fragment and the species delimitations were based on the genetic distance, phylogenetic analysis, and morphology. Three earlier described species were identified in the recently collected material and further 10 species are described: C. pallescens sp. nov., C. bicolor sp. nov., C. craterensis sp. nov., C. motykai sp. nov., C. mindikensis sp. nov., C. kailakiensis sp. nov., C. manokwarensis sp. nov., C. haiaensis sp. nov., C. humeralis sp. nov., and C. boceki sp. nov. DNA-based identifications provided some ambiguous results and closely related species could not be robustly delimited using solely molecular data. Additionally, the species limits were based on clearly defined morphological characters and the morphological differentiation was found unlinked from the genetic divergence. Colour patterns cannot be used for identification because all species available in more specimens were polymorphic and followed various local co-mimics. The Papuan fauna of Cladophorus is very diverse and the closely related species regularly occur in limited regions. Differentiation within restricted ranges is therefore considered as the main speciation mode. 


Phytotaxa ◽  
2018 ◽  
Vol 350 (1) ◽  
pp. 1
Author(s):  
RUI-HONG WANG ◽  
MAO-QIN XIA ◽  
JIN-BO TAN ◽  
CHUAN CHEN ◽  
XIN-JIE JIN ◽  
...  

A new species, Scrophularia jinii (Scrophulariaceae), from Central China is described and illustrated. This new species was formerly misidentified as S. fargesii, from which it differs in many morphological characters. Moreover, it is distinct with all known Scrophularia species in its unique deeply double serrate leaf margin with 3–7 big teeth on each side. Molecular phylogenetic analysis further supports its species delimitation and suggests a close relationship with several Japanese and North American species.


2021 ◽  
Author(s):  
Hyun Lee ◽  
Komsit Wissitrassameewong ◽  
Myung Soo Park ◽  
Jonathan J. Fong ◽  
Annemieke Verbeken ◽  
...  

Abstract Lactifluus (Pers.) Roussel is an ectomycorrhizal genus that was recently recognized to be distinct from the genus Lactarius. To date, 216 Lactifluus species have been reported worldwide. Misidentification of Lactifluus species is common because of intraspecific morphological variation, cryptic diversity, and the limited number of taxonomic keys available. Molecular data are indispensable for species delimitation; a multilocus phylogenetic analysis showed that most Asian Lactifluus species are not conspecific with morphologically similar species present on other continents. In particular, Korea has misused European and North American Lactifluus names. In this study, we evaluated the taxonomy of Lactifluus in Korea using both morphological and multilocus molecular (ITS, nrLSU, rpb1, and rpb2) data. We examined 199 Lactifluus specimens collected between 1980 and 2016, and a total of 24 species across the four Lactifluus subgenera were identified. All Korean species are distinct and clearly separated from European and North American species. Five taxa corresponded to previously described species from Asia and the remaining 19 taxa are confirmed as new species. Herein, we provide keys to the Korean Lactifluus species within their subgenera, molecular phylogenies, a summary of diversity, and detailed description of the new species.


Phytotaxa ◽  
2016 ◽  
Vol 260 (2) ◽  
pp. 157 ◽  
Author(s):  
JAMES W. BYNG ◽  
BENEDETTA BERNARDINI ◽  
MAARTEN J. M. CHRISTENHUSZ ◽  
MARK W. CHASE

Relationships of Ixonanthaceae and Irvingiaceae have been poorly known in the past. We therefore investigate the relationships of these families here. Plastid atpB, rbcL and ndhF sequences from taxa representing all genera were analysed using maximum likelihood. Allantospermum was found as sister to Irvingiaceae and does not belong to Ixonanthaceae where it was often traditionally placed. This position of Allantospermum in Irvingiaceae is further supported by numerous putative synapomorphic characters. Expanded species sampling in Ixonanthaceae found that African Phyllocosmus was embedded within a strongly supported clade containing American Ochthocosmus. A re-evaluation of morphological characters of the two supports an enlarged concept of Ochthocosmus. Within Irvingiaceae, the West African monotypic Desbordesia was embedded within a strongly supported clade of Old World Irvingia. These findings change circumscriptions of both Ixonanthaceae and Irvingiaceae.


Nematology ◽  
2015 ◽  
Vol 17 (4) ◽  
pp. 377-400 ◽  
Author(s):  
Kimkhuy Khun ◽  
Wilfrida Decraemer ◽  
Marjolein Couvreur ◽  
Gerrit Karssen ◽  
Hanne Steel ◽  
...  

Hirschmanniella mucronatapopulations isolated from two Cambodian provinces were characterised using morphological, morphometric and molecular criteria. Examination of 1024 specimens from 60 different paddy fields revealed high intraspecific variation in morphology and morphometrics, especially in tail terminus shape and stylet length. Sequence results confirmed that morphologically divergent individuals represent a single species, suggesting that neglecting morphological variation has led to an overestimation ofHirschmannielladiversity in former studies. Phylogenetic analysis of the SSU, D2-D3, LSU and ITS1-5.8S-ITS2 regions revealed three concordant clades,H. mucronatahaving a sister relationship withH. kwazunaandH. loofi. Plotting the diagnostic features, including tail terminus shape, stylet length and lip region morphology on the phylogenetic framework, revealed that none of them supported the clades and represented convergent features. All three molecular markers were able to discriminate allHirschmanniellaspecies, but the D2-D3 region was the easiest, fastest and most successful region to be amplified. Species delimitation and the diagnostic features ofHirschmanniellawere re-evaluated.Hirschmanniella abnormalis and H. exactaare considered to be junior synonyms ofH. oryzaeandH. mannaiaspecies inquirenda. Finally, a list of valid species with indication of synonyms and a polytomous key are provided.


2019 ◽  
Vol 95 (1) ◽  
pp. 49-64 ◽  
Author(s):  
Felipe Polivanov Ottoni ◽  
José L. O. Mattos ◽  
Axel M. Katz ◽  
Pedro H.N. Bragança

Three distinct and independent molecular-based species delimitation analyses were performed among the species and populations included within theAustraloherosautranigroup, based on sequences of the mitochondrial gene Cytochrome b: a tree-based method proposed by Wiens and Penkrot (WP), a Character-based DNA Barcoding (CBB) and coalescent species delimitation method termed the Bayesian Implementation of the Poisson tree processes (bPTP). The congruence of WP and CBB delimited 11 independent lineages (species), while the bPTP delimited just nine lineages. We did not favour any of the methods, and we considered the possibility of two slightly variant scenarios. A time-calibrated phylogenetic analysis is proposed based on the predominant congruence of the results of these three species delimitation methods herein applied. The monophyly of theA.autranispecies group was highly supported with maximum node support value and diagnosed by 11 nucleotide substitutions. The sister clade of theA.autranispecies group is the clade comprisingA.sp. Timbé do Sul andA.minuano. The phylogenetic analysis supports three main clades within theA.autranispecies group, supported by maximum node support value, with the Southern Mata Atlântica clade as the most basal clade. Divergence time estimates indicate that the diversification of theAustraloherosoriginated during the early Neogene, but only in the late Neogene did the processes of diversification in the southeast and north regions occur. Diversification within theAustraloherosautranispecies group occurred synchronically for the three main clades during the beginning of the Quaternary. It is demonstrated that molecular characters are valuable tools for species recognition, particularly in speciose groups with inconspicuous or difficult to record morphological characters. The resulting phylogeny of theAustraloherosautranigroup is highly compatible with the geological and biogeographic scenarios proposed for the Neogene and Quarternary shaping of the extant river basins of eastern Brazil. Despite the origin of theA.autranigroup being dated to the late Miocene, species level diversification occurred in the Pleistocene and was probably driven by headwater capture events and sea-level fluctuations.


2006 ◽  
Vol 19 (1) ◽  
pp. 59 ◽  
Author(s):  
D. Nicolle ◽  
M. A. Whalen ◽  
D. A. Mackay

Morphological variation within Eucalyptus series Subulatae, a group of mallee and woodland tree taxa distributed across southern Australia, was assessed by adult and seedling characteristics. A phenetic study included a total of 51 adult morphological characters and 37 seedling characters, which were assessed for 564 individuals representing 163 populations, covering the broad geographical distribution of the series. All taxa included in the series by either Johnson and Hill (1999) or Brooker (2000) were included together with E. angustissima, E. cooperiana, E. falcata and E. salmonophloia, all of which have been at times included in, or considered closely related to, E. ser. Subulatae. The phenetic analyses indicate that the four subseries of Brooker (2000) are morphologically distinct, although their distinctiveness is only evident from seedling characters. The two subseries that Johnson and Hill (1999) recognise (subser. Flocktonianosae and Transcontinentalosae) corresponding to Brooker’s (2000) subser. Decurrentes, are more weakly defined. Southern populations of E. dolichocera are not considered here to belong to this species but rather to belong to a different subseries based on seedling morphology. A phylogenetic analysis of 44 morphological characters and 23 species of E. ser. Subulatae and 24 species from variously related taxa suggest that E. ser. Subulatae may not be monophyletic. Eucalyptus brockwayi and E. salmonophloia are basal to E. ser. Subulatae and all of the other taxa included in the analysis. Within E. ser. Subulatae, subsers Oleaginae and Spirales are both monophyletic. Both the phylogenetic and phenetic analyses strongly suggest that E. brockwayi is unique in several characters, including some not previously recognised, and is best placed in a monotypic series. The position of E. aspersa remains unresolved, but is probably best retained in E. subser. Decussatae. A key to the subseries of E. ser. Subulatae is presented and putative intersubserial, interserial and intersectional hybrids involving the series are cited.


Phytotaxa ◽  
2020 ◽  
Vol 456 (3) ◽  
pp. 219-243 ◽  
Author(s):  
DEAN P. PHILLIPS ◽  
BENNY BYTEBIER

Based on a published morphological and phylogenetic analysis, species delimitation in Stenoglottis is here revised, and five species (six taxa) are now recognized: S. fimbriata (with two varieties), S. longifolia, S. inandensis, S. woodii, and S. macloughlinii. Stenoglottis fimbriata subsp. saxicola and S. zambesiaca are synonymised here with S. fimbriata, S. modesta is reduced in rank to S. fimbriata var. modesta and S. molweniensis is synonymised with S. longifolia. The three spurred species, S. inandensis, S. woodii and S. macloughlinii, are retained. We include revised descriptions, diagnoses and a morphological key, in which characteristics of the floral spurs, labella, leaves, bracts, and auricles contribute most clearly to distinguishing the taxa. Distributions maps and photos showing important diagnostic characters and morphological variation are also presented.


Zootaxa ◽  
2007 ◽  
Vol 1627 (1) ◽  
pp. 23-39 ◽  
Author(s):  
NATAN M. MACIEL ◽  
REUBER A. BRANDÃO ◽  
LEANDRO A. CAMPOS ◽  
ANTONIO SEBBEN

A new toad, Rhinella cerradensis, is described, including its tadpole and the advertisement call. The new species occupies Cerrado habitats in the Brazilian states of Piauí, Bahia, Goiás, Minas Gerais, and Distrito Federal. The species is characterized by its large size; absence of tibial glands; well developed cranial crests; short hands; sexually dimorphic coloration; and by the absence of a spiracle tube of the tadpole. The new species is included in the Rhinella marina group by the presence of a jagged suture formed by the articulation between the pterygoid medial ramus and the parasphenoid alae, as well as other shared morphological features. Morphological characters and statistical analyses inferred by morphometric feature suggest the existence of two subgroups of species within R. marina group. However, taxonomic rearrangements are not made here and await phylogenetic analysis.


Sign in / Sign up

Export Citation Format

Share Document