Redescription of Amphioctopus ovulum (Sasaki, 1917) (Cephalopoda : Octopodidae) and comparative morphological analyses among three species of violet-ringed octopods

2020 ◽  
Author(s):  
Yan Tang ◽  
Xiaodong Zheng ◽  
Qi Li
Keyword(s):  
Coastal Waters ◽  
Phylogenetic Trees ◽  
Morphological Characters ◽  
Mitochondrial Genes ◽  
The East China Sea ◽  
Morphometric Characters ◽  
China Sea ◽  
Terminal Organ ◽  
The Gulf Of Thailand ◽  
The Web

Amphioctopus ovulum (Sasaki, 1917) is a small to moderate-sized octopus, which can be identified by the iridescent violet ring present in the dark ocellus on the web between the bases of arms II and III. Comprehensive taxonomic review is required to fully characterise this species because the syntypes are missing and the description is insufficiently complete for modern octopod taxonomy. In this study, the species A. ovulum is redescribed with morphological and morphometric characters of 18 specimens collected from the coastal waters of China. The distribution of A. ovulum extends from the Gulf of Thailand, through Cambodia, Vietnam, Philippines, through the South China Sea and the East China Sea to Japan. The swollen terminal organ diverticulum and long spermatophores make it possible to distinguish A. ovulum clearly from A. rex and A. neglectus, species with similar morphological characters of violet rings. Moreover, three species of violet-ringed octopods were clearly differentiated by sequences of the partial mitochondrial genes COI and COIII. Three monophyletic clades resolved in phylogenetic trees. Amphioctopus rex and A. neglectus clustered into a sister taxon, and clustered with the remaining Amphioctopus species.

Alkaline phosphatase activities and regulation in three harmful Prorocentrum species from the coastal waters of the East China Sea

2019 ◽  
Vol 79 (2) ◽  
pp. 459-471 ◽  
Author(s):  
Linjian Ou ◽  
Xianling Qin ◽  
Xiaoyong Shi ◽  
Qingliang Feng ◽  
Shuwen Zhang ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
East China Sea ◽  
Coastal Waters ◽  
East China ◽  
The East China Sea ◽  
Phosphatase Activities ◽  
China Sea

Morphology and molecular analyses of a newClytiaspecies (Cnidaria: Hydrozoa: Campanulariidae) from the East China Sea

2014 ◽  
Vol 95 (2) ◽  
pp. 289-300 ◽  
Author(s):  
Jinru He ◽  
Lianming Zheng ◽  
Wenjing Zhang ◽  
Yuanshao Lin ◽  
Wenqing Cao
Keyword(s):  
New Species ◽  
East China Sea ◽  
Coastal Waters ◽  
Phylogenetic Analyses ◽  
Coi Gene ◽  
East China ◽  
The East China Sea ◽  
Separate Species ◽  
Molecular Analyses ◽  
China Sea

The near-cosmopolitan genusClytiais abundantly found in coastal waters, but difficulties of identification in this genus make nearly all species records of medusae suspect. Complex life histories, ambiguous taxonomic characters, and phenotypic plasticity pose serious problems for accurate species-level identifications and future revisions ofClytiaspecies. In the present study, morphological investigations and molecular analyses ofClytiaspecimens from the coastal waters of the East China Sea revealedClytia gulangensissp. nov. as a new species. DNA barcoding based on the mitochondrial cytochrome oxidase I (COI) gene supported the new species as a separate species withinClytia, and phylogenetic analyses based on mitochondrial 16S rDNA and nuclear 18S rDNA further confirmed this new species to be a distinct lineage. Moreover, detailed observation of medusae and polyps of this species showed sufficient morphological differences from otherClytiaspecies for a diagnosis. Our results indicated that life cycle and DNA-based studies should be a standard approach in future biodiversity investigations ofClytiaspecies.

Redescription of Robsonella fontaniana (Cephalopoda: Octopodidae)

2008 ◽  
Vol 88 (3) ◽  
pp. 617-624 ◽  
Author(s):  
C.M. Ibáñez ◽  
R.D. Sepúlveda ◽  
J. Guerrero ◽  
J. Chong
Keyword(s):  
Sexual Dimorphism ◽  
Morphological Characters ◽  
South Coast ◽  
Lateral Tooth ◽  
Zoological Museum ◽  
Adult Males ◽  
Morphometric Characters ◽  
Terminal Organ ◽  
The Family ◽  
Central South

The genus Robsonella Adam, 1938 belongs to the family Octopodidae and can only be identified by some characters present in males. In this work the species Robsonella fontaniana is redescribed from morphological and morphometric characters of 33 specimens (21 males and 12 females) collected on the central-south coast of Chile, during the years 2003 and 2004, and of 11 specimens (three males and eight females) obtained from the Zoological Museum of Hamburg. New diagnoses for the genus Robsonella and the species R. fontaniana are provided. Sexual dimorphism in R. fontaniana is evident by adult males having enlarged suckers and a shorter third right arm compared to the females. Some morphological characters such as ligula, radula and terminal organ diverticulum make it possible to distinguish this genus clearly from other genera. The ligula of the hectocotylized arm in Robsonella is characterized by a longitudinal groove, rounded tip, large calamus and seven copulatory lamellae. In addition, the first lateral tooth in the radula is crescent-shaped; this allows the identification of Robsonella regardless of sex.

Phylogeny of Trematomus (Notothenioidei: Nototheniidae) inferred from mitochondrial and nuclear gene sequences

2009 ◽  
Vol 21 (6) ◽  
pp. 565-570 ◽  
Author(s):  
Kristen L. Kuhn ◽  
Thomas J. Near
Keyword(s):  
Dna Sequences ◽  
Phylogenetic Relationships ◽  
Phylogenetic Trees ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Nuclear Gene ◽  
Single Copy ◽  
Morphological Characters ◽  
Mitochondrial Genes ◽  
Phylogenetic Resolution

AbstractThe biota of Antarctica is amazingly rich and highly endemic. The phylogenetics of notothenioid fishes has been extensively investigated through analyses of morphological characters, DNA sequences from mitochondrial genes, and single copy nuclear genes. These phylogenetic analyses have produced reasonably similar phylogenetic trees of notothenioids, however a number of phylogenetic questions remain. The nototheniid clade Trematomus is an example of a group where phylogenetic relationships remain unresolved. In this paper we revisit the phylogenetic relationships of Trematomus using both increased taxon sampling and an expanded dataset which includes DNA sequences from two mitochondrial genes (ND2 and 16S rRNA) and one single-copy nuclear gene (RPS7). The Bayesian phylogeny resulting from the analysis of the combined mitochondrial and nuclear gene datasets was well resolved and contained more interspecific nodes supported with significant Bayesian posteriors than either the mitochondrial or nuclear gene phylogenies alone. This demonstrates that the addition of nuclear gene sequence data to mitochondrial data can enhance phylogenetic resolution and increase node support. Additionally, the results of the combined mitochondrial and nuclear Bayesian analyses provide further support for the inclusion of species previously classified as Pagothenia and Cryothenia in Trematomus.

The distribution of dissolved lead in the coastal waters of the East China Sea

2014 ◽  
Vol 85 (2) ◽  
pp. 700-709 ◽  
Author(s):  
Yan Li ◽  
Rujun Yang ◽  
Aibin Zhang ◽  
Shirong Wang
Keyword(s):  
East China Sea ◽  
Coastal Waters ◽  
East China ◽  
The East China Sea ◽  
China Sea
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