Morphological and molecular characterisation of Longidorus pinus sp. n. (Nematoda: Longidoridae) from China and a key to known species of Longidorus in China

Nematology ◽  
2018 ◽  
Vol 20 (7) ◽  
pp. 617-639 ◽  
Author(s):  
Yumei Xu ◽  
Weimin Ye ◽  
Jianming Wang ◽  
Zengqi Zhao

Summary Longidorus pinus sp. n. from China is characterised by females 3.3-4.9 mm long; lip region 8-12 μm diam., distinctly offset by a constriction; amphidial fovea pocket-shaped without basal lobes; a short odontostyle (67-81 μm); anteriorly located guide ring (30-38 μm); and short and conoid tail (31-40 μm long, c = 84-138, c′ = 1.2-1.9), with one or two pairs of caudal pores on each side. Males were not found. Three developmental juvenile stages were identified, the first-stage juvenile with conoid tail (c′ = 2.4-2.9). The polytomous key codes for the new species are: A2(3), B1, C23, D4, E1, F2, G23, H23, I1, J2, K6. Molecular phylogenetic analyses based on SSU, D2-D3 of LSU, ITS1 and ITS2 rDNA sequences indicate that L. pinus sp. n. is closely related to L. hangzhouensis, L. asiaticus, and L. camelliae, all of which apparently share a common Asiatic geographic origin. In addition, a key for identification of Longidorus found in China, based on morphological characters of both female and first-stage juvenile, is provided.

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.


Nematology ◽  
2017 ◽  
Vol 19 (8) ◽  
pp. 951-970 ◽  
Author(s):  
Yumei Xu ◽  
Kai Guo ◽  
Weimin Ye ◽  
Jianming Wang ◽  
Jingwu Zheng ◽  
...  

Longidorus juglanssp. nov. is a new needle nematode detected from the rhizosphere of a walnut tree in Shanxi Province, P.R. China. It was distinguished by female body length of 3.9-5.2 mm; lip region 14-18 μm wide, rounded and continuous, amphidial fovea pocket-shaped without distinct basal lobes; moderately long odontostyle (125-140 μm); guide ring at mid-odontostyle and situated 69-78 μm from anterior end; short and blunt conoid tail (30-41 μm long, c = 118-147, c′ = 0.6-0.9), bearing 2-3 caudal pores on each side. The male ofL. juglanssp. nov. is 5.1 mm long, with 13 ventro-median supplements, a short and blunt conoid tail bearing 3-4 caudal pores on each side, and spicules 73 μm long. Three developmental juvenile stages were recognised. This new species is very similar to another Chinese speciesL. fangiin general morphology, but can be distinguished by the number of juvenile stages and DNA sequences of SSU, ITS1, ITS2 and D2-D3 of LSU rDNA. Morphological and molecular characterisation was provided forL. fangirepresenting two new geographical records. The phylogenetic relationships among these species were analysed using data from SSU, D2-D3 of LSU, ITS1 and ITS2 rDNA, which revealed thatL. juglanssp. nov. andL. fangiwere clustered together withL. diadecturus,L. litchiiandL. jonesiwhose guide ring is located at mid-odontostyle level.


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.


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 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 ◽  
2015 ◽  
Vol 204 (3) ◽  
pp. 203 ◽  
Author(s):  
Zdenko Tkalčec ◽  
Armin Mešić ◽  
Chun-Ying Deng ◽  
Bruna Pleše ◽  
Helena Ćetković

Hymenoporus paradoxus, a new marasmioid fungal species belonging to the new genus is described from southern China. It differs from all other marasmioid species by a true tubular hymenophore, a character previously unknown in marasmioid fungi, and from all other tubular agarics by a hymenophore attached to a free collarium, and central, tough, dark and filiform stipe. The additional diagnostic characters are small basidiocarps, mostly convex pileus, smooth, hyaline, non-amyloid spores, densely packed dendriform cheilocystidia, and pileipellis composed of repent hyphae densely covered with simple to coralloid excrescences, intermixed with dendriform cells. As peculiar morphological characters had indicated, molecular phylogenetic analyses based on the 28S rDNA sequences confirm phylogenetic position of the new species in Omphalotaceae and a need to establish a new genus. Color photographs of macro- and micromorphological characters, SEM microphotographs, and a phylogenetic tree based on the partial 28S rDNA gene are provided.


2021 ◽  
Vol 307 (2) ◽  
Author(s):  
Pau Carnicero ◽  
Núria Garcia-Jacas ◽  
Llorenç Sáez ◽  
Theophanis Constantinidis ◽  
Mercè Galbany-Casals

AbstractThe eastern Mediterranean basin hosts a remarkably high plant diversity. Historical connections between currently isolated areas across the Aegean region and long-distance dispersal events have been invoked to explain current distribution patterns of species. According to most recent treatments, at least two Cymbalaria species occur in this area, Cymbalaria microcalyx and C. longipes. The former comprises several intraspecific taxa, treated at different ranks by different authors based on morphological data, evidencing the need of a taxonomic revision. Additionally, some populations of C. microcalyx show exclusive morphological characters that do not match any described taxon. Here, we aim to shed light on the systematics of eastern Mediterranean Cymbalaria and to propose a classification informed by various sources of evidence. We performed molecular phylogenetic analyses using ITS, 3’ETS, ndhF and rpl32-trnL sequences and estimated the ploidy level of some taxa performing relative genome size measures. Molecular data combined with morphology support the division of traditionally delimited C. microcalyx into C. acutiloba, C. microcalyx and C. minor, corresponding to well-delimited nrDNA lineages. Furthermore, we propose to combine C. microcalyx subsp. paradoxa at the species level. A group of specimens previously thought to belong to Cymbalaria microcalyx constitute a well-defined phylogenetic and morphological entity and are described here as a new species, Cymbalaria spetae. Cymbalaria longipes is non-monophyletic, but characterized by being glabrous and diploid, unlike other eastern species. The nrDNA data suggest at least two dispersals from the mainland to the Aegean Islands, potentially facilitated by marine regressions.


2021 ◽  
pp. 1-28
Author(s):  
Yoshimasa Kumekawa ◽  
Haruka Fujimoto ◽  
Osamu Miura ◽  
Ryo Arakawa ◽  
Jun Yokoyama ◽  
...  

Abstract Harvestmen (Arachnida: Opiliones) are soil animals with extremely low dispersal abilities that experienced allopatric differentiation. To clarify the morphological and phylogenetic differentiation of the endemic harvestman Zepedanulus ishikawai (Suzuki, 1971) (Laniatores: Epedanidae) in the southern part of the Ryukyu Archipelago, we conducted molecular phylogenetic analyses and divergence time estimates based on CO1 and 16S rRNA sequences of mtDNA, the 28S rRNA sequence of nrDNA, and the external morphology. A phylogenetic tree based on mtDNA sequences indicated that individuals of Z. ishikawai were monophyletic and were divided into clade I and clade II. This was supported by the nrDNA phylogenetic tree. Although clades I and II were distributed sympatrically on all three islands examined (Ishigaki, Iriomote, and Yonaguni), heterogeneity could not be detected by polymerase chain reaction–restriction fragment length polymorphism of nrDNA, indicating that clades I and II do not have a history of hybridisation. Also, several morphological characters differed significantly between individuals of clade I and clade II. The longstanding isolation of the southern Ryukyus from the surrounding islands enabled estimation of the original morphological characters of both clades of Z. ishikawai.


2021 ◽  
Vol 99 (2) ◽  
pp. 398-412
Author(s):  
Marcelo R. Pace ◽  
Brenda Hernández-Hernández ◽  
Esteban M. Martínez Salas ◽  
Lúcia G. Lohmann ◽  
N. Ivalu Cacho

Background: Astianthus is a monospecific arborescent genus of Bignoniaceae that occur in the Pacific Coast of central Mexico and northern Central America, where it grows in dense populations along riversides. Its phylogenetic placement has remained controversial since Astianthus has unusual morphological characters such as a four-loculed ovary, and simple, pulvinate, verticillate leaves. Methods: Here we used three plastid markers ndhF, rbcL, and trnL-F, wood, and bark anatomical data to investigate the phylogenetic placement of Astianthus and assign it to one of Bignoniaceae’s main clades. Results: Our molecular phylogenetic analyses indicated that Astianthus belongs in tribe Tecomeae s.s., where other charismatic Neotropical Bignoniaceae genera such as Campsis and Tecoma are currently placed. Wood and bark anatomy support this placement, as Astianthus reunites a unique combination of features only known from members of Tecomeae s.s., such as storied axial parenchyma, the co-occurrence of homo- and heterocellular rays, septate fibers, and scattered phloem fibers in the bark. Conclusions: The placement of Astianthus within Tecomeae s.s. provides further support to previous proposals for the Neotropical origin of this Pantropical tribe.


Zootaxa ◽  
2019 ◽  
Vol 4603 (1) ◽  
pp. 105
Author(s):  
FAN XIN ◽  
SI-YU ZHANG ◽  
YONG-SHI SHI ◽  
LEI WANG ◽  
YU ZHANG ◽  
...  

In this study, two new brackish-water species of Macrostomum (M. shenda n. sp. and M. spiriger n. sp.) collected from Shenzhen, China, were described based on morphological, histological, and molecular phylogenetic analyses. Macrostomum shenda n. sp. differs from its congeners in the oblique and non-thickening distal opening of its narrow funnel-shaped stylet. In addition, its sperm have neither bristles nor brush, and are surrounded by an undulating membrane in the mid-body region. In M. spiriger n. sp., the stylet is spirally twisted. Its reproductive apparatus has a seminal bursal pore opening exteriorly. Results of the 18S and 28S rDNA phylogenetic analyses also support the establishments of these two new species. Moreover, the 18S and 28S rDNA sequences of some species within Macrostomum in previous studies have been revised to avoid ambiguity, while Macrostomum dongyuanensis Wang & Sun, 2015 was re-identified as a new record of M. quiritium Kolasa, 1973 from China.


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