Description, molecular characterization and life cycle of Serpentirhabdias mussuranae n. sp. (Nematoda: Rhabdiasidae) from Clelia clelia (Reptilia: Colubroidea) in Brazil

2019 ◽  
Vol 94 ◽  
Author(s):  
Y. Kuzmin ◽  
V.V. Tkach ◽  
F.T.V. Melo
Keyword(s):  
New Species ◽  
Life Cycle ◽  
Nuclear Ribosomal Dna ◽  
Free Living ◽  
Larval Stages ◽  
Triangular Shape ◽  
Oral Opening ◽  
Molecular Phylogenetic ◽  
Apical View ◽  
Amazonas State

Abstract Serpentirhabdias mussuranae n. sp. is described from the lungs of the mussurana, Clelia clelia (Daudin, 1803), from vicinities of Lábrea, Amazonas State, Brazil. The species is characterized by the triangular oral opening, the presence of teeth (onchia) in the oesophastome, the excretory glands longer than the oesophagus and the tail abruptly narrowing in its anterior half and gradually tapering in posterior half. Among the Neotropical representatives of the genus, three species are known to possess the onchia in the oesophastome: S. atroxi, S. moi and S. viperidicus. Serpentirhabdias mussuranae n. sp. differs from S. atroxi and S. viperidicus by its triangular shape of the oral opening and the oesophastome in apical view, vs. round in the latter two congeners. Additionally, S. viperidicus has a larger oesophastome, 13–22 micrometers wide and 13–23 micrometers deep. The new species has relatively longer excretory glands than S. moi. The new species is morphologically and genetically close to S. atroxi, S. moi and S. viperidicus, all parasitic in Brazilian snakes, based on the presence of onchia and the comparison of nucleotide sequences of nuclear ribosomal DNA and mitochondrial cox1 gene (differences varied between 3.8% and 7.1%). Data on the life cycle of S. mussuranae n. sp. is provided, and the life cycle is typical of the genus Serpentirhabdias, with the combination of direct development and heterogony. Free-living larval stages and the adults of amphimictic free-living generation are described. The results of molecular phylogenetic analysis based on nuclear ribosomal internal transcribed spacer (ITS) + partial 28S region and partial mitochondrial cox1 gene are provided.

Life Cycles

2001 ◽  
Author(s):  
Jan A. Pechenik
Keyword(s):  
Life Cycle ◽  
Genetic Material ◽  
Life Cycles ◽  
Offspring Size ◽  
Free Living ◽  
Complex Life Cycles ◽  
Volume Number ◽  
Larval Stages ◽  
Underlying Mechanisms ◽  
Life Cycle Evolution

I have a Hardin cartoon on my office door. It shows a series of animals thinking about the meaning of life. In sequence, we see a lobe-finned fish, a salamander, a lizard, and a monkey, all thinking, “Eat, survive, reproduce; eat, survive, reproduce.” Then comes man: “What's it all about?” he wonders. Organisms live to reproduce. The ultimate selective pressure on any organism is to survive long enough and well enough to pass genetic material to a next generation that will also be successful in reproducing. In this sense, then, every morphological, physiological, biochemical, or behavioral adaptation contributes to reproductive success, making the field of life cycle evolution a very broad one indeed. Key components include mode of sexuality, age and size at first reproduction (Roff, this volume), number of reproductive episodes in a lifetime, offspring size (Messina and Fox, this volume), fecundity, the extent to which parents protect their offspring and how that protection is achieved, source of nutrition during development, survival to maturity, the consequences of shifts in any of these components, and the underlying mechanisms responsible for such shifts. Many of these issues are dealt with in other chapters. Here I focus exclusively on animals, and on a particularly widespread sort of life cycle that includes at least two ecologically distinct free-living stages. Such “complex life cycles” (Istock 1967) are especially common among amphibians and fishes (Hall and Wake 1999), and within most invertebrate groups, including insects (Gilbert and Frieden 1981), crustaceans, bivalves, gastropods, polychaete worms, echinoderms, bryozoans, and corals and other cnidarians (Thorson 1950). In such life cycles, the juvenile or adult stage is reached by metamorphosing from a preceding, free-living larval stage. In many species, metamorphosis involves a veritable revolution in morphology, ecology, behavior, and physiology, sometimes taking place in as little as a few minutes or a few hours. In addition to the issues already mentioned, key components of such complex life cycles include the timing of metamorphosis (i.e., when it occurs), the size at which larvae metamorphose, and the consequences of metamorphosing at particular times or at particular sizes. The potential advantages of including larval stages in the life history have been much discussed.

Larval and life-cycle patterns in echinoderms

2001 ◽  
Vol 79 (7) ◽  
pp. 1125-1170 ◽  
Author(s):  
Larry R McEdward ◽  
Benjamin G Miner
Keyword(s):  
Life Cycle ◽  
Free Living ◽  
Larval Body ◽  
Evolutionary Transitions ◽  
Developmental Patterns ◽  
Developmental Evolution ◽  
Larval Stages ◽  
Two Factors ◽  
Life Cycle Patterns ◽  
Life Cycle Evolution

We review the literature on larval development of 182 asteroids, 20 crinoids, 177 echinoids, 69 holothuroids, and 67 ophiuroids. For each class, we describe the various larval types, common features of a larval body plan, developmental patterns in terms of life-cycle character states and sequences of larval stages, phylogenetic distribution of these traits, and infer evolutionary transitions that account for the documented diversity. Asteroids, echinoids, holothuroids, and ophiuroids, but not crinoids, have feeding larvae. All five classes have evolved nonfeeding larvae. Direct development has been documented in asteroids, echinoids, and ophiuroids. Facultative planktotrophy has been documented only in echinoids. It is surprising that benthic, free-living, feeding larvae have not been reported in echinoderms. From this review, we conclude that it is the ecological and functional demands on larvae which impose limits on developmental evolution and determine the associations of larval types and life-cycle character states that give rise to the developmental patterns that we observe in echinoderms. Two factors seriously limit analyses of larval and life-cycle evolution in echinoderms. First is the limited understanding of developmental diversity and second is the lack of good phylogenies.

The life cycle of Parvatrema homoeotecnum sp.nov.(Trematoda: Digenea) and a review of the family Gymnophallidae Morozov, 1955

Parasitology ◽  
1964 ◽  
Vol 54 (1) ◽  
pp. 1-41 ◽  
Author(s):  
B. L. James
Keyword(s):  
Life Cycle ◽  
Intermediate Host ◽  
Technical Assistance ◽  
Littorina Saxatilis ◽  
Free Living ◽  
Diagnostic Features ◽  
Late Professor ◽  
Larval Stages ◽  
The Family ◽  
Haematopus Ostralegus

1. Parvatrema homoeotecnum sp.nov. from the oystercatcher, Haematopus ostralegus occidentalis Neumann at Aberystwyth is described and compared with other species of the genus.2. The life cycle of this species is unique. The larval stages occur in the gastropod, Littorina saxatilis (Olivi) subsp. tenebrosa (Montagu) and include germinal sacs which have a structure and development similar to an adult digenean. There are no free-living stages and only one intermediate host.3. The significance of this unique life cycle is discussed.4. The family Gymnophallidae Morozov, 1955, is reviewed. Emended definitions are given for the family, subfamilies and genera. Keys, diagnostic features and brief notes of the species are included.I am very grateful to Dr Gwendolen Rees, who suggested the investigation which led to the discovery of this species, for her advice and indispensable assistance throughout the work and the preparation of this paper. I am also grateful to the late Professor T. A. Stephenson for his interest and for the provision of working facilities; to Mr W. A. Ballantine, Mr A. H. Clarke, Jr., Mr C. Curtis, Miss G. P. F. Evans, Dr V. Fretter, Professor L. A. Harvey, Mr D. H. Jones and Dr J. Lewis who sent me specimens of Littorina saxatilis; to Professor R. M. Cable and Emerit. Professor G. R. La Rue for helpful suggestions; to Mr J. R. Hirst and Mr D. Hemingway Jones for photographic and technical assistance and to the Department of Scientific and Industrial Research for a grant which made the work possible.

Ontogeny of the proetoid trilobite Stenoblepharum, and relationships of a new species from the Upper Ordovician of Argentina

1997 ◽  
Vol 71 (3) ◽  
pp. 419-433 ◽  
Author(s):  
Gregory D. Edgecombe ◽  
Brian D. E. Chatterton ◽  
Norberto E. Vaccari ◽  
Beatriz G. Waisfeld
Keyword(s):  
New Species ◽  
Life Cycle ◽  
Cladistic Analysis ◽  
Sister Group ◽  
San Juan ◽  
Upper Ordovician ◽  
Growth Series ◽  
Larval Stages ◽  
A New Species

Silicified material from the Early Caradoc part of the Las Aguaditas Formation in San Juan Province, Argentina, includes a nearly complete growth series for a new species of the tropidocoryphid Stenoblepharum Owens, 1973. Cladistic analysis of Stenoblepharum species indicates that S. astinii new species is most closely allied to the Early Caradoc S. strasburgense (Cooper, 1953) from Virginia. Chinese species of Stenoblepharum are sister group to a Baltic/Laurentian clade. A single adult-like protaspid stage occurs in the life cycle of S. astinii, closely resembling the protaspis of Decoroproetus. It is preceded by a non-adult-like first protaspid instar that appears to be characteristic of Proetoidea in general but contrasts markedly with the early larval stages of other taxa in Proetida.

The morphology of free-living stages and immature parasites of Rhabdias paraensis (Nematoda: Rhabdiasidae), a parasite of Rhinella marina (Anura: Bufonidae) in Brazil

2016 ◽  
Vol 61 (1) ◽  
Author(s):  
Francisco Tiago de Vasconcelos Melo ◽  
Luciana de Cássia Silva do Nascimento ◽  
Lilian Cristina Macedo ◽  
Jeannie Nascimento dos Santos ◽  
Yuriy Kuzmin
Keyword(s):  
Life Cycle ◽  
Buccal Capsule ◽  
Original Description ◽  
Species Determination ◽  
Free Living ◽  
Rhinella Marina ◽  
Additional Information ◽  
New Information ◽  
Apical View

AbstractRhabdias paraensis Santos, Melo, Nascimento, Nascimento, Giese et Furtado, 2011 was described based on fully gravid worms. Further investigations on the free-living stages, immature worms and young individuals were facilitated by cultivation in the laboratory, which allowed us to add new information about the morphology and development of the species. Observations on the free-living development of R. paraensis showed that the life cycle is typical of Rhabdias, with alternation of gonochoristic and hermaphroditic generations and without homogony. Males of the free-living generation were different from those in several species of the genus studied previously. In the original description, the excretory glands and duct were absent in gravid specimens of R. paraensis, while in this study, distinct excretory glands and a duct were observed in immature and young individuals. Additionally, we recognised the separation of the buccal capsule walls into anterior and posterior portions and described the specific shapes of these portions in lateral and apical view. Studies on the morphology and development of free-living stages of Rhabdias spp. from Neotropical regions may provide additional information for species determination.

scholarly journals Euphorbia mbuinzauensis, a new succulent species in Kenya from the Synadenium group in Euphorbia sect. Monadenium (Euphorbiaceae)

PhytoKeys ◽  
2021 ◽  
Vol 183 ◽  
pp. 21-35
Author(s):  
Neng Wei ◽  
Fredrick Munyao Mutie ◽  
Geoffrey Mwachala ◽  
Olwen M. Grace ◽  
Guang-Wan Hu ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Ribosomal Dna ◽  
Phylogenetic Inference ◽  
Distinct Species ◽  
Nuclear Ribosomal Dna ◽  
Molecular Phylogenetic Analysis ◽  
Molecular Phylogenetic ◽  
Smooth Margin ◽  
Iucn Criteria

Euphorbia mbuinzauensis, a succulent new species of the Synadenium group in Euphorbiaceae from Makueni County, Kenya, is described and illustrated. Morphologically, it is most similar to E. pseudomollis, but differs mainly by its shrubby habit (up to 4 m), abaxial leaves surfaces with densely stellate hairs, 2–4-forked cymes, smaller bracts (ca. 2.5 × 3.0 mm), smaller cyathia (6 mm wide), crimson glands without narrow smooth margin, smaller fruits (ca. 8 × 7 mm) and ovoid seeds (ca. 1.8 × 2.2 mm). Furthermore, we performed a molecular phylogenetic analysis of the Synadenium group in Euphorbia sect. Monadenium, based on complete nuclear ribosomal DNA (nrDNA) datasets. This phylogenetic inference also supports it to be a distinct species. The new species is assessed as Endangered using the IUCN criteria.

Pseudosperma albobrunneum sp. nov. from coniferous forests of Pakistan

Mycotaxon ◽  
2021 ◽  
Vol 136 (2) ◽  
pp. 361-372
Author(s):  
Sana Jabeen ◽  
Zainab ◽  
Hira Bashir ◽  
Abdul Nasir Khalid
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Its Region ◽  
Morphological Characters ◽  
Molecular Data ◽  
Nuclear Ribosomal Dna ◽  
Coniferous Forests ◽  
Molecular Phylogenetic ◽  
Khyber Pakhtunkhwa Province ◽  
A New Species

A new species, Pseudosperma albobrunneum, is described and illustrated. The specimens are from different areas of Khyber Pakhtunkhwa province, Pakistan. The identification is based on morphological characters, in combination with molecular phylogenetic analysis of sequences of the ITS region of nuclear ribosomal DNA. The species is found distinct morphologically from all closely related taxa, and molecular data confirm its novelty.

Morphological characteristics and phylogenetic analyses revealed a new Calocybe (Lyophyllaceae, Basidiomycota) species from northeast China

Phytotaxa ◽  
2021 ◽  
Vol 490 (2) ◽  
pp. 203-210
Author(s):  
JIZE XU ◽  
XIAODONG YU ◽  
CHUNLAN ZHANG ◽  
YU LI
Keyword(s):  
New Species ◽  
Internal Transcribed Spacer ◽  
Northeast China ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Morphological Characteristics ◽  
Nuclear Ribosomal Dna ◽  
Full Description ◽  
Molecular Phylogenetic ◽  
A New Species

A new species, Calocybe decurrens, is illustrated and described in detail based on morphological characteristics and phylogenetic analyses. Calocybe decurrens is mainly characterized by its decurrent gills and by its stipe that discolors upon maturation. Molecular phylogenetic analyses were based on the internal transcribed spacer (ITS1-5.8S-ITS2) and the large subunit of the nuclear ribosomal DNA (nrLSU) sequences. The results indicated that its affiliation is in genus Calocybe, where it occupies an isolated position. A full description, color images, illustrations and a phylogenetic tree to show the placement of the new species are provided.

Russula darjeelingensis, a new species from Eastern Himalaya, India

Phytotaxa ◽  
2018 ◽  
Vol 358 (1) ◽  
pp. 83 ◽  
Author(s):  
SOUMITRA PALOI ◽  
KANAD DAS ◽  
KRISHNENDU ACHARYA
Keyword(s):  
New Species ◽  
Ribosomal Dna ◽  
Internal Transcribed Spacer ◽  
Phylogenetic Analyses ◽  
Nuclear Ribosomal Dna ◽  
Eastern Himalaya ◽  
Morphological Description ◽  
Molecular Phylogenetic ◽  
Internal Transcribed Spacer Sequences ◽  
A New Species

Russula darjeelingensis is characterized by its small sized white pileus with a tall and narrow stipe, white spore print, basidiospores with amyloid suprahilar spot and a pileipellis containing encrusted pileocystidia and absence of primordial hyphae. The combination of all these characters and molecular phylogenetic analyses of internal transcribed spacer sequences of nuclear ribosomal DNA confirmed it as a new species in genus Russula Pers., subg. Russula Romagn. emend. sect. Polychromae (Maire) Sarnari subsect. Paraintegrinae Sarnari. A comprehensive morphological description, illustrations, and comparisons with morphologically similar and phylogenetically related species are provided in the present study.

The life cycle ofGyliauchen volubilisNagaty, (Digenea: Gyliauchenidae) from the Red Sea

2011 ◽  
Vol 86 (2) ◽  
pp. 165-172 ◽  
Author(s):  
M.O. Al-Jahdali ◽  
R.M. El-Said Hassanine
Keyword(s):  
Life Cycle ◽  
Post Infection ◽  
Aquatic Vegetation ◽  
Life Cycles ◽  
Gulf Of Aqaba ◽  
Larval Stages ◽  
Phylogenetic Studies ◽  
Molecular Phylogenetic ◽  
Second Intermediate Host ◽  
Siganus Rivulatus

AbstractAlthough nothing is known about gyliauchenid life cycles, molecular phylogenetic studies have placed the Gyliauchenidae Fukui, 1929 close to the Lepocreadiidae Odhner, 1905. The gyliauchenidGyliauchen volubilisNagaty, 1956 was found in the intestine of its type-host,Siganus rivulatus, a siganid fish permanently resident in a lagoon within the mangrove swamps on the Egyptian coast of the Gulf of Aqaba. Larval forms of this trematode (mother sporocysts, rediae and cercariae) were found in the gonads and digestive gland ofClypeomorus clypeomorus(Gastropoda: Cerithiidae), a common snail in the same lagoon. So, this life cycle ofG. volubiliswas elucidated under natural conditions: eggs are directly ingested by the snail; mother sporocysts and rediae reach their maturity 3–6 and 11–13 weeks post-infection; rediae contain 23–29 developing cercariae; fully developed cercariae are gymnocephalus, without penetration glands, emerge from the snail during the night 16–18 weeks post-infection and rapidly encyst on aquatic vegetation (no second intermediate host); encysted metacercariae are not progenetic; 4-day-old metacercariae encysted on filamentous algae fed toS. rivulatusdeveloped into fully mature worms 6–8 weeks post-infection. The cycle was completed in about 26 weeks and followed one of the three known patterns of lepocreadiid life cycles, and except for the gymnocephalus cercariae, the other larval stages are very similar to those of lepocreadiids. Generally, the life cycle ofG. volubilisimplicitly supports the phylogenetic relationship of Gyliauchenidae and Lepocreadiidae inferred from molecular phylogenetic studies.

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