Combining morphological and molecular data to classify Laxus sakihariiae sp. n., a new stilbonematine nematode (Nematoda: Desmodoridae) from the coast of Sesoko Island, Japan

Nematology ◽  
2018 ◽  
Vol 20 (1) ◽  
pp. 81-95 ◽  
Author(s):  
Daniel Leduc ◽  
Frederic Sinniger

Because of their relatively simple body plan, the number of morphological characters used to differentiate between closely related nematode genera is often limited. In addition, boundaries among genera sometimes become blurred due to the appearance of new trait combinations as more new species are described. Molecular phylogenetic analyses can address the shortcomings of morphological taxonomy by clarifying relationships among closely related species and genera and can help identify which morphological characters are taxonomically informative. Here, we describeLaxus sakihariiaesp. n. from shallow subtidal sands on Sesoko Island in the Okinawa prefecture, investigate phylogenetic relationships with other stilbonematine species and genera based on SSU rDNA sequences, and provide the first LSU rDNA sequence for the subfamily. The new species can be easily distinguished from all other species of the genus by the presence in the male of subventral and ventral rows of stout and spine-like setae in the pre- and postcloacal regions. This feature suggests affinities with the closely related genusLeptonemella, although the SSU consensus tree clearly shows that the new species forms a monophyletic clade together with the otherLaxusspecies for which sequences are available. The structure of the cephalic capsule inL. sakihariiaesp. n., which consists of a block layer between the median and basal zones of the cephalic cuticle, is consistent with the placement of this species. This trait is not currently used as a diagnostic feature, but our finding suggests that the structure of the cephalic capsule may be taxonomically useful for differentiating between some stilbonematine genera.

Phytotaxa ◽  
2018 ◽  
Vol 345 (1) ◽  
pp. 35 ◽  
Author(s):  
BIAO XU ◽  
UWE BRAUN ◽  
SHANHE ZHANG ◽  
HUI YANG ◽  
ZHI CAO ◽  
...  

Bauhinia species are popular ornamental and medicinal plants with a pantropical distribution. In December 2016, powdery mildew symptoms were found on B. blakeana and B. purpurea in Guangdong, China. Based on ITS and 28S rDNA sequences, as well as morphological characters, the powdery mildew was identified as Erysiphe lespedezae. Previous records of powdery mildews on Bauhinia spp. are discussed. Based on morphological and molecular phylogenetic analyses of type material, Pseudoidium caesalpiniacearum is reduced to synonymy with E. lespedezae. To our best knowledge, this is the first report of E. lespedezae causing powdery mildew on B. purpurea in China, and B. blakeana as a new host. A detailed morphological description and molecular data are provided herein.


Author(s):  
Nikita A. Martynenko ◽  
Evgeniy S. Gusev ◽  
Pavel V. Kulizin ◽  
Elena E. Guseva ◽  
Kevin McCartney ◽  
...  

A new species, Cryptomonas uralensis Martynenko, Gusev, Kulizin & Guseva sp. nov., is described from western slopes of the Ural Mountains (Russia) based on morphological and molecular data. Phylogenetic relationships inferred from nuclear SSU and LSU rDNA sequences show that the new species forms a clade with C. tetrapyrenoidosa Skuja emend. Hoef-Emden & Melkonian. Comparison of secondary structures of nuclear rDNA ITS2, including analysis of Compensatory Base Changes (CBC), confirms the separation between C. uralensis sp. nov. and C. tetrapyrenoidosa. Cell morphology and sizes of C. uralensis sp. nov. are very similar to C. tetrapyrenoidosa and C. pyrenoidifera, and C. uralensis sp. nov. may thus represent a species that can only be reliably identified using molecular data.


2020 ◽  
Vol 61 (1) ◽  
Author(s):  
Jian-Sheng Wang ◽  
Yi-Fei Lu ◽  
Yue-Liang Xu ◽  
Shui-Hu Jin ◽  
Xiao-Feng Jin

Abstract Background Southeast Asia, together with tropical Africa, Madagascar, South India and Sri Lanka, and the eastern Himalayas, are the five primary hotspots of species diversity of Impatiens (Balsaminaceae). China is also rich in Impatiens species, especially in the limestone karsts or ‘Danxia’ landforms. With zygomorphic flowers and diverse corolla morphology and color, the species in Impatiens are well-known for their ornamental use, but they are also notorious in taxonomy. During the preparation of revision of Impatiens in Zhejiang and adjacent regions, an unknown species was collected from Mt. Wuyi in Fujian Province, Southeast China. Results Phylogenetic analyses based on nuclear ITS, chloroplast atpB-rbcL and trnL-F sequences, together with micromorphology of pollen grains and seed coats, strongly supported the close relationship of the new species with Impatiens platysepala Y.L.Chen and I. chloroxantha Y.L.Chen. In turn, both molecular data and morphological characters also were sufficient to distinguish the new species from the other two counterparts. Conclusions Our detailed morphological observations and molecular phylogenetic analyses support the recognition of Impatiens wuyiensis as a species new to science.


Phytotaxa ◽  
2021 ◽  
Vol 478 (2) ◽  
pp. 261-267
Author(s):  
MENG ZHOU ◽  
JIA-JIA CHEN ◽  
JOSEF VLASÁK ◽  
YUAN YUAN

Dentipellicula guyanensis, a new species of Hericiaceae, is described and illustrated based on morphological characters and supported by molecular phylogenetic analyses using ITS and nLSU rDNA sequences. D. guyanensis is characterized by an annual and resupinate growth habit, a monomitic hyphal structure with non-amyloid, non-dextrinoid and acyanophilous generative hyphae, the presence of gloeoplerous hyphae in hymenophoral trama, the presence of gloeocystidia, and rough basidiospores measuring as 2.8–3.1 × 1.9–2.1 µm. A key to accepted species of Dentipellicula is provided.


2019 ◽  
Vol 94 ◽  
Author(s):  
S.V. Shchenkov ◽  
S.A. Denisova ◽  
G.A. Kremnev ◽  
A.A. Dobrovolskij

Abstract The phylogenetic position of most xiphidiocercariae from subgroups Cercariae virgulae and Cercariae microcotylae remains unknown or unclear, even at the family level. In this paper, we studied the morphology and molecular phylogeny of 15 microcotylous and virgulate cercariae (11 new and four previously described ones). Based on morphological and molecular data, we suggested five distinct morphological types of xiphidiocercariae, which are a practical alternative to Cercariae virgulae and Cercariae microcotylae subgroups. Four of these types correspond to actual digenean taxa (Microphallidae, Lecithodendriidae, Pleurogenidae and Prosthogonimidae), while the fifth is represented by Cercaria nigrospora Wergun, 1957, which we classified on the basis of molecular data for the first time. We reassessed the relative importance of morphological characters used for the classification of virgulate and microcotylous cercariae, and discussed the main evolutionary trends within xiphidiocercariae. Now stylet cercariae can be reliably placed into several sub-taxa of Microphalloidea on the basis of their morphological features.


Phytotaxa ◽  
2017 ◽  
Vol 311 (2) ◽  
pp. 155 ◽  
Author(s):  
NATALY GÓMEZ-MONTOYA ◽  
ELISANDRO RICARDO DRECHSLER-SANTOS ◽  
VALÉRIA FERREIRA-LOPES ◽  
MICHAL TOMŠOVSKÝ ◽  
CARLOS URCELAY ◽  
...  

Based on molecular evidence and morphological analyses, a new species in the genus Trametopsis is revealed. Trametopsis aborigena sp. nov. is proposed and described from South America. Molecular phylogenetic analyses of ITS and LSU rDNA sequences suggest that Trametopsis cervina seems to encompass more than one species and confirm previous results showing that Antrodiella brasiliensis groups with Trametopsis. The morphological analyses of type specimens of A. brasiliensis and A. luteocontexta revealed a shared morphological pattern with Trametopsis and their combinations in Trametopsis are proposed. The circumscription of Trametopsis is discussed since all the studied specimens revealed a previously overlooked arrangement of characters, i.e., cylindrical and slightly curved to allantoid basidiospores and a metachromatic hyphal system monomitic in the context and dimitic in the tubes.


Zootaxa ◽  
2017 ◽  
Vol 4226 (2) ◽  
pp. 229 ◽  
Author(s):  
W. DAI ◽  
J.N. ZAHNISER ◽  
C.A. VIRAKTAMATH ◽  
M.D. WEBB

A new tribe of the leafhopper subfamily Deltocephalinae, Punctulini tribe nov., from China, India, Thailand, and Fiji is described and includes three new genera and five new species: Punctulus gen. nov. includes P. tumidifrons sp. nov. from China, P. manipurensis from India, and P. lobatus sp. nov. from Thailand; Hirsutula gen. nov. includes H. rubrifrons sp. nov. from Thailand; and Taveunius gen. nov. includes T. megapunctatus sp. nov., from Fiji. A key to the genera of Punctulini is provided. Observations on the shared morphological characters of Punctulini with the superficially similar tribe Magnentiini, and with Vartini to which it is found to be related based on phylogenetic analyses of morphological and molecular data including newly available sequences and analyses, are made and discussed. Afrovarta Zahniser 2013 is removed from Vartini and placed in Athysanini, placement nov. 


Phytotaxa ◽  
2016 ◽  
Vol 289 (1) ◽  
pp. 59 ◽  
Author(s):  
DIOGO X. LIMA ◽  
KERSTIN VOIGT ◽  
CARLOS A.F. DE SOUZA ◽  
RAFAEL J.V. DE OLIVEIRA ◽  
CRISTINA M. SOUZA-MOTTA ◽  
...  

The Backusella genus comprises mucoralean saprobes that inhabit in mainly soil and form transitorily curved (when young, erect at maturity) sporangiophores arising directly from the substratum, with simultaneous production of both sporangia and sporangiola. During a study of Mucorales in soil from an Atlantic Rainforest in Pernambuco, Brazil, one specimen of Backusella was isolated and characterized based on morphological, physiological and molecular data (ITS1-5.8S-ITS2 and LSU rDNA sequences). The phylogenetic analyses of the isolate revealed that it belongs to the Backusellaceae and is closely related to species of Backusella. The specimen grew better at 25ºC, with no development at 40ºC, and presented conical and cylindrical columellae possessing a central constriction as well as subglobose sporangiospores 7.5–15 × 5.5–10 µm. Based on the evidences of the analyzed datasets, a new species of Backusella is proposed and a taxonomic key for the species of this genus is provided.


Phytotaxa ◽  
2018 ◽  
Vol 350 (1) ◽  
pp. 64
Author(s):  
CHAO-QUN WANG ◽  
MING ZHANG ◽  
TAI-HUI LI

A new species in genus Neohygrocybe sect. Neohygrocybe, N. griseonigra, is described from the Chebaling National Nature Reserve in Guangdong province, China. It is characterized by its dark brown dry fibrillose pileus, whitish to grayish white lamellae that stain red then dark gray or blackish when bruised, smooth basidiospores, long sterigmata of basidia, and lanceolate pseudocystidia. Molecular phylogenetic analyses based on the ITS rDNA sequences also confirm the taxonomic status of the new species as the morphological characters indicated. A key to all known members of Neohygrocybe is provided in this study.


Phytotaxa ◽  
2018 ◽  
Vol 340 (2) ◽  
pp. 157 ◽  
Author(s):  
K. P. DEEPNA LATHA ◽  
K. N. ANIL RAJ ◽  
PATINJAREVEETTIL MANIMOHAN

Two new species of Rhodocollybia, R. ciliatomarginata and R. brevipes, are described from Kerala State, India, based on morphological and molecular data. Comprehensive descriptions, photographs, and comparisons with phenetically similar and phylogenetically related species are provided. Molecular phylogenetic analysis based on nrITS-rDNA sequences coupled with morphology confirmed both the novelty of these species and their placement in the genus Rhodocollybia. The present study forms the first documentation of the genus Rhodocollybia from south Asia.


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