scholarly journals Reproductive system and spermatozoa ultrastructure support the phylogenetic proximity of Megadasys and Crasiella (Gastrotricha, Macrodasyida)

2014 ◽  
Vol 83 (2) ◽  
pp. 119-131 ◽  
Author(s):  
Loretta Guidi ◽  
M. Antonio Todaro ◽  
Marco Ferraguti ◽  
Maria Balsamo
Keyword(s):  
Reproductive System ◽  
Phylogenetic Study ◽  
Simultaneous Hermaphrodite ◽  
Basal Region ◽  
Mitochondrial Complex ◽  
Thin Region ◽  
Molecular Phylogenetic Study ◽  
The Family ◽  
Close Relationship ◽  
Molecular Phylogenetic

The reproductive system and the spermatozoon of Megadasys sterreri from Lanzarote (Canary Islands, Spain) were studied at structural and ultrastructural levels. The species is a simultaneous hermaphrodite with cross-fertilization and shows paired gonads, the male anterior and the female posterior, and both gametes mature in a caudo-cephalic direction. Sperm ducts converge on the midline and open into a ventral common pore. Two sexual accessory organs are present in the caudal trunk. A pipe-like frontal organ lies between the ovaries and the caudal organ, and is composed of a long, thin region connected to a large zone containing mature and degenerating spermatozoa. The cigar-like caudal organ is elongate, bulky and is made of an anterior glandulo-muscular region and a posterior muscular one. Spermatozoa are long, filiform cells formed by an acrosome, a nucleus-mitochondrial complex, and a flagellum. The long acrosome is composed of an apical twisted region and a basal straight region. The nucleo-mitochondrial complex is formed by a spring-shaped nucleus surrounding basally the mitochondrion and apically a granular material. The flagellum has a 9x2+2 axoneme, characterized by a dense and prominent central sheath surrounding the central tubules. Megadasys sterreri (Cephalodasyidae) shows the same reproductive layout as Crasiella (Planodasyidae): paired gonads, caudo-cephalic maturation of gametes, sperm ducts converging into a common ventral pore, and two sexual accessory organs. Also the spermatozoa ultrastructure shows two similarities in the two genera: a peculiar prominent central sheath in the axoneme and a similar structure of the basal region of the acrosome. Considering the likely polyphyletic nature of the family Cephalodasyidae, and the sister- taxon relationship of Megadasys and Crasiella that emerged from a recent molecular phylogenetic study, a close relationship between the two taxa appears to be very likely; consequently, we propose to remove Megadasys from the family Cephalodasyidae and affiliate it to the family Planodasyidae.

scholarly journals A revision of the African genus Mesanthemum (Eriocaulaceae)

Kew Bulletin ◽  
2019 ◽  
Vol 74 (4) ◽  
Author(s):  
Yuxi Liang ◽  
Sylvia M. Phillips ◽  
Martin Cheek ◽  
Isabel Larridon
Keyword(s):  
New Genus ◽  
Phylogenetic Study ◽  
Taxonomic Descriptions ◽  
Molecular Phylogenetic Study ◽  
The Family ◽  
Molecular Phylogenetic ◽  
Perennial Herbs ◽  
Ephemeral Species ◽  
A New Species ◽  
African Genus

SummaryMesanthemum is a genus comprising 16 species in the family Eriocaulaceae and is native to Africa and Madagascar. Eriocaulaceae are characterised by a basal tuft or rosette of narrow leaves and small flowers in heads. Mesanthemum can be recognised by diplostemonous flowers and fused glandular pistillate petals. While most Mesanthemum species are large perennial herbs, two small ephemeral species from West Africa, M. albidum and M. auratum differ from the rest of the genus by their shorter life cycle, smaller size, simpler floral structures and different seed surface patterning. A molecular phylogenetic study, morphological comparisons and scanning electron microscope (SEM) examination of seed coat sculpture were carried out to determine whether they should be separated as a new genus. The molecular results indicate that the two ephemeral species are nested in the Mesanthemum clade. However, they are not closely related to each other. All species of Mesanthemum are here revised, including the description of a new species M. alenicola from Equatorial Guinea. An identification key is provided, together with taxonomic descriptions, synonymy and notes. Images of the seeds as seen under SEM are provided where available. Lectotypifications are provided for Mesanthemum albidum, M. bennae, M. pilosum, M. prescottianum, M. pubescens and M. variabile. A neotype is selected for M. rutenbergianum, which is synonymised with M. pubescens.

A morphology-based phylogenetic analysis of Fasciolariidae (Gastropoda: Buccinoidea)

Zootaxa ◽  
2019 ◽  
Vol 4684 (1) ◽  
pp. 1-65
Author(s):  
DIOGO R. COUTO ◽  
LUIZ R. L. R. SIMONE
Keyword(s):  
Morphological Data ◽  
Phylogenetic Study ◽  
Similar Species ◽  
Molecular Phylogenetic Study ◽  
The Family ◽  
Basal Clade ◽  
Morphological Approach ◽  
Molecular Phylogenetic ◽  
Taxonomic Groups ◽  
The Tropics

Fasciolariids are buccinoid neogastropods and key predators in the tropics and subtropics, comprising more than 500 species in the subfamilies Fasciolariinae, Fusininae and Peristerniinae. Tulip shells, horse-conchs, spindles, etc., have been grouped into heterogeneous combinations of unrelated species, while several generic names have been used to group conchologically similar species. The latest molecular phylogenetic study conflicts with the current circumscription of many genera, and even more so, with the three currently recognized subfamilies. This work is the first morphological approach to the phylogeny of fasciolariids, using a parsimony analysis in TnT of 53 taxa based on 100 characters. This analysis reveals a monophyletic Fasciolariidae, with the genera Dolicholatirus and Teralatirus representing the most basal clade in the family, followed by three nodes that correspond to a fusinine grade, which includes the genus Pseudolatirus (Peristerniinae). A terminal clade groups the peristerniine genera Peristernia and Fusolatirus, fasciolariines and the remaining peristerniines. Although none of these clades correspond to currently accepted taxonomic groups, the latter two clades are corroborated in the most recent multilocus molecular phylogeny. This study supports the utility of morphological data in the recovery of groups, even in the molecular era. 

Mycetia griffithii, a new name for Mycetia angustifolia (Hook.f.) Razafim. & B.Bremer (Rubiaceae)

Phytotaxa ◽  
2016 ◽  
Vol 252 (3) ◽  
pp. 231
Author(s):  
DONG-XIAN XU ◽  
SYLVAIN G. RAZAFIMANDIMBISON ◽  
ZHU-QIU SONG
Keyword(s):  
South China ◽  
Phylogenetic Study ◽  
New Combinations ◽  
New Name ◽  
Molecular Phylogenetic Study ◽  
The Family ◽  
Distinct Genus ◽  
Molecular Phylogenetic

Myrioneuron R. Brown ex J. D. Hooker in Bentham & Hooker (1873: 69) comprises about eight species of the family Rubiaceae and it is distributed in East Himalaya to South China (Govaerts et al. 2011). Although it was occasionally treated as a synonym of Mycetia Reinwardt (1825: 9) (Bakhuizen 1975) or Keenania J. D. Hooker (1880: 101) (Van Steenis 1987, Robbrecht 1988), most botanists accepted it as a distinct genus (Kurz 1877, Hooker 1880, Schumann 1891, Pitard 1923, Merrill 1942, Bremekamp 1952, Deb 1996, Lo 1999, Wright 1999, Kress et al. 2003; Chen & Taylor 2011, Govaerts et al. 2011). Most recently, however, a molecular phylogenetic study revealed that Myrioneuron and Mycetia are non-monophyletic and intermixed, and therefore both taxa were combined to represent a monophyletic genus and Mycetia was accepted as its generic name (Ginter et al. 2015). In the study, they published nine new combinations, including Mycetia angustifolia (J. D. Hooker 1880: 97) Razafim. & B. Bremer in Ginter et al. (2015: 293). However, this name is illegitimate because it is a later homonym of Mycetia angustifolia Ridley (1923: 68), in accordance with Article 53.1 of the ICN (McNeil et al. 2012).

scholarly journals Two new species of the genus Meleonoma Meyrick from China (Lepidoptera, Gelechioidea, Xyloryctidae)

ZooKeys ◽  
2019 ◽  
Vol 871 ◽  
pp. 79-87 ◽  
Author(s):  
Aihui Yin ◽  
Yanpeng Cai
Keyword(s):  
New Species ◽  
Male Genitalia ◽  
Taxonomic Position ◽  
Phylogenetic Study ◽  
Guangxi Province ◽  
Southeastern China ◽  
Molecular Phylogenetic Study ◽  
The Family ◽  
Two New Species ◽  
Molecular Phylogenetic

Two new species of Meleonoma Meyrick, 1914a (Gelechioidea, Xyloryctidae) from southeastern China are described: Meleonoma foliiformis Yin, sp. nov. from Guangxi Province and M. projecta Yin, sp. nov. from Fujian Province. Adults and male genitalia are described in detail. A list of the Meleonoma species occurring in China is given. The taxonomic position of Meleonoma has been unstable, and under debate. Nonetheless, it is here tentatively placed in the family Xyloryctidae, following the latest molecular phylogenetic study concerning this genus.

scholarly journals Taxonomic Monograph of Saxicolella (Podostemaceae), African waterfall plants highly threatened by Hydro-Electric projects, with five new species.

2021 ◽  
Author(s):  
Martin Cheek ◽  
Denise Molmou ◽  
Sekou Magassouba ◽  
Jean Paul Ghogue
Keyword(s):  
Sierra Leone ◽  
Extinction Risk ◽  
Sensu Stricto ◽  
Risk Assessments ◽  
Phylogenetic Study ◽  
Molecular Phylogenetic Study ◽  
The Family ◽  
Molecular Phylogenetic ◽  
Distribution And Ecology ◽  
Silt Load

The genus Saxicolella Engl. (Podostemaceae) are African rheophytes, restricted to rapids and waterfalls as are all members of the family. Previously, Saxicolella sensu lato was shown to be polyphyletic with two separate clades in the molecular phylogenetic study of Koi et al. (2012). The name Pohliella Engl. was recently resurrected for one clade that is sister to the American genera Ceratolacis (Tul.)Wedd., Podostemum Michx. and all Old World Podostemoideae (podostemoids) (Cheek 2020). Pohliella has distichous phyllotaxy, bilocular ovaries, filiform roots with paired holdfasts, and rootcaps. The second clade, Saxicolella sensu stricto, including the type of the generic name, has spiral phyllotaxy, unilocular ovaries, ribbon-like or crustose roots that lack both holdfasts and rootcaps. Saxicolella sensu stricto, sampled from the type species, S. nana Engl. of Cameroon, is embedded within and near the base of the major clade of African podostemoids and is sister to all other African genera apart from Inversodicraea R.E.Fr. and Monandriella Engl. Recently reduced to three species in Cameroon and S.E. Nigeria by the resurrection of Pohliella (3 to 4 species in Ghana and Nigeria and Cameroon), Saxicolella sensu stricto is expanded to eight species in this monograph by description of five new taxa. Saxicolella futa Cheek and S. deniseae Cheek are newly described from Guinea, S. ijim Cheek from Cameroon, the informally named S. sp. A from Gabon, and S. angola Cheek from Angola. The known geographic range of the genus is thus expanded c. 2,500 km westwards to Guinea from eastern Nigeria and c.1,500 km southeastwards from Cameroon to Cuanza do Sul, Angola. The greatest concentration of species occurs in the Cross Sanaga interval of western Cameroon and eastern Nigeria, with three species. Cameroon (3 species) followed by Nigeria and Guinea (2 species each) are the countries with highest species diversity. The genus can be expected to be found in Sierra Leone, Liberia, Ivory Coast and Congo Republic. A classification is proposed grouping the species into three subgenera (Saxicolella, Butumia (G.Taylor) Cheek comb. et. stat. nov. and Kinkonia Cheek subgen. nov.) based on root morphology and shoot position and morphology. The discovery, morphology, circumscription, distribution, and ecology of Saxicolella is reviewed, an identification key to the species is presented, together with descriptions, synonymy, links to illustrations, and extinction risk assessments for each of the eight species now recognised. All of the species are provisionally assessed as either Endangered or Critically Endangered using the IUCN 2012 standard, making this genus among the most threatened of its size globally. The major threats, above all, are hydro-electric projects. Saxicolella deniseae may already be globally extinct, and two of the four known locations of S. angola appear lost, S. sp. A of Gabon is threatened at at least one of its three locations, while Saxicolella futa is threatened at all three locations, all due to incipient or active hydro electric projects. Contamination of watercourses by increased turbidity from silt-load due anthropic changes and by eutrophication from pollution are also threats for the majority of the species.

A pilot study on the molecular phylogeny of Drepanoidea (Insecta: Lepidoptera) inferred from the nuclear gene EF-1α and the mitochondrial gene COI

2009 ◽  
Vol 100 (2) ◽  
pp. 207-216 ◽  
Author(s):  
C.G. Wu ◽  
H.X. Han ◽  
D.Y. Xue
Keyword(s):  
Mitochondrial Gene ◽  
Nuclear Gene ◽  
Phylogenetic Study ◽  
Sister Relationship ◽  
Molecular Phylogenetic Study ◽  
The Family ◽  
Molecular Phylogenetic ◽  
Gene Coi ◽  
Coi Sequences ◽  
Definition Of

AbstractA molecular phylogenetic study of the Drepanoidea based on the EF-1α sequences and combined EF-1α and COI sequences was carried out in order to infer higher classification at and above the subfamily level. The sample contained 14 taxa representing 13 genera recognized in the Drepanoidea. The results revealed that the Drepaninae, Thyatirinae and Cyclidiinae respectively form monophyletic groups. The sister relationship between the Drepaninae and the Thyatirinae was validated. The monophyly of the Cyclidiinae with the Drepaninae+Thyatirinae was supported robustly.Hypsomadius insignisandOreta vatamawithin the traditional definition of the Drepaninae formed an individual clade with robust support (100%) and constitutes a sister relationship to a clade containing the rest of the Drepaninae in all the topologies, which means that the subfamily Oretinae of the Drepanidae should be restored. The family Drepanidae is divided into four subfamilies: Drepaninae, Oretinae, Thyatirinae and Cyclidiinae in this work. The family Epicopeiidae formed a monophyly with high bootstrap values. The result of combined analysis of EF-1α and COI showed that the Epicopeiidae have a closer phylogenetic relationship with the Geometridae than with the Drepanidae and belong to neither the Drepanoidea nor the Geometroidea.

Description of Ditylenchus acantholimonis n. sp. (Rhabditida: Anguinidae) from Iran, a morphological and molecular phylogenetic study

Nematology ◽  
2021 ◽  
pp. 1-10
Author(s):  
Samira Aliverdi ◽  
Ebrahim Pourjam ◽  
Majid Pedram
Keyword(s):  
New Species ◽  
Rhizosphere Soil ◽  
Phylogenetic Analyses ◽  
Phylogenetic Study ◽  
Pharyngeal Bulb ◽  
Lateral Field ◽  
Molecular Phylogenetic Study ◽  
Molecular Phylogenetic ◽  
Golestan Province ◽  
Tail Tip

Summary Ditylenchus acantholimonis n. sp. is described based on morphological, morphometric and molecular characters. It was isolated from the rhizosphere soil of Acantholimon sp. in Golestan province, Iran, and is mainly characterised by having four lines in the lateral field, a pyriform to bottle-shaped offset pharyngeal bulb, post-vulval uterine sac 36.6-56.1% of the vulva to anus distance long, and a subcylindrical to conical tail with widely rounded tip. It is further characterised by short to medium-sized females, 480-617 μm long, with a fine stylet having small rounded knobs, V = 80.8-83.6, c = 11.0-13.8, c′ = 3.3-4.6, and males with 16.0-17.0 μm long spicules. The new species was morphologically compared with six species having four lines in their lateral field, rounded tail tip and comparable morphometric data namely: D. dipsacoideus, D. emus, D. exilis, D. paraparvus, D. sturhani, and D. solani. It was also compared with two species, D. ferepolitor and D. angustus, forming a maximally supported clade in the 18S tree. The phylogenetic analyses using the maximal number of Anguinidae and several Sphaerularioidea genera based upon partial 18S and 28S rDNA D2-D3 sequences revealed that Ditylenchus is polyphyletic. In the 18S tree, the new species formed a clade with D. ferepolitor (KJ636374) and D. angustus (AJ966483); in the 28S tree it formed a poorly supported clade with D. phyllobios (KT192618) and Ditylenchus sp. (MG865719).

scholarly journals A molecular phylogenetic study of the caecal fluke of poultry, Postharmostomum commutatum (= P. gallinum) (Trematoda: Brachylaimidae)

2018 ◽  
Vol 117 (12) ◽  
pp. 3927-3934 ◽  
Author(s):  
Marisa C. Valadão ◽  
Beatriz C. M. Silva ◽  
Danimar López-Hernández ◽  
Jackson V. Araújo ◽  
Sean A. Locke ◽  
...  
Keyword(s):  
Phylogenetic Study ◽  
Molecular Phylogenetic Study ◽  
Molecular Phylogenetic

Molecular phylogeny of Pemphiginae (Hemiptera: Aphididae) inferred from nuclear gene EF-1α sequences

2008 ◽  
Vol 98 (5) ◽  
pp. 499-507 ◽  
Author(s):  
H.C. Zhang ◽  
G.X. Qiao
Keyword(s):  
Phylogenetic Analysis ◽  
Molecular Phylogeny ◽  
Host Specificity ◽  
Nuclear Gene ◽  
Molecular Data ◽  
Molecular Phylogenetic Analysis ◽  
Phylogenetic Study ◽  
Primary Host ◽  
Molecular Phylogenetic Study ◽  
Molecular Phylogenetic

AbstractThree traditional tribes of Fordini, Pemphigini and Eriosomatini comprise Pemphiginae, and there are two subtribes in Fordini and Pemphigini, respectively. Most of the species in this subfamily live heteroecious holocyclic lives with distinct primary host specificity. The three tribes of Pemphigini (except Prociphilina), Eriosomatini and Fordini use three families of plants, Salicaceae (Populus), Ulmaceae (Ulums) and Anacardiaceae (Pistacia and Rhus), as primary hosts, respectively, and form galls on them. Therefore, the Pemphigids are well known as gall makers, and their galls can be divided into true galls and pseudo-galls in type. We performed the first molecular phylogenetic study of Pemphiginae based on molecular data (EF-1α sequences). Results show that Pemphiginae is probably not a monophylum, but the monophyly of Fordini is supported robustly. The monophyly of Pemphigini is not supported, and two subtribes in it, Pemphigina and Prociphilina, are suggested to be raised to tribal level, equal with Fordini and Eriosomatini. The molecular phylogenetic analysis does not show definite relationships among the four tribes of Pemphiginae, as in the previous phylogenetic study based on morphology. It seems that the four tribes radiated at nearly the same time and then evolved independently. Based on this, we can speculate that galls originated independently four times in the four tribes, and there is no evidence to support that true galls are preceded by pseudo-galls, as in the case of thrips and willow sawflies.

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