Progressing diversification and biogeography of the mesopelagic Nematoscelis (Crustacea: Euphausiacea) in the Atlantic

2021 ◽  
Author(s):  
D N Kulagin ◽  
A A Lunina ◽  
U V Simakova ◽  
A L Vereshchaka
Keyword(s):  
Molecular Phylogenetics ◽  
Coi Gene ◽  
Geographic Isolation ◽  
Evolutionary Mechanisms ◽  
Linked Gene ◽  
Mitochondrial Coi ◽  
Speciation Model ◽  
Mitochondrial Coi Gene ◽  
Primary Driver

Abstract Evolutionary mechanisms driving the diversification of pelagic animals remain poorly understood, partly due to the high levels of gene flow in the open ocean. We use molecular phylogenetics, morphological, and phylogeographic approaches to test the allopatric speciation model in respect to the Atlantic krill genus Nematoscelis. Based on our observations, we hypothesize that diversification in genus Nematoscelis may occur through three progressing stages: (i) populations separated geographically and divergence occurred in the mitochondrial COI gene only (Nematoscelis megalops, one clade of Nematoscelis tenella), (ii) morphology diverged (clades of Nematoscelis microps and Nematoscelis atlantica), and (iii) the nuclear H3 gene diverged (clades of N. tenella). Our results confirm allopatric expectations and the dispersal-limiting speciation model. We propose that the primary driver of diversification is geographic isolation coupled with hydrology-linked gene barriers at ∼14–22°N (new) and ∼30°S. The second driver preventing hybridization of diverged populations is linked to external morphology, i.e. enlarged photophores and chitin saddles on the pleon of males, which facilitate sexual selection by female choice. Same-male forms, even belonging to different species, rarely co-occur, which makes the selection effective and not biased. Our results implicate a significant role of non-copulatory characters in Nematoscelis speciation.

A review of the genus Forficuloecus Conci (Phthiraptera: Philopteridae) from parrots (Psittaciformes: Psittacidae), with descriptions of four new species

Zootaxa ◽  
2008 ◽  
Vol 1859 (1) ◽  
pp. 49 ◽  
Author(s):  
ROGER D. PRICE ◽  
KEVIN P. JOHNSON ◽  
RICARDO L. PALMA
Keyword(s):  
New Species ◽  
Coi Gene ◽  
Chewing Louse ◽  
Mitochondrial Coi ◽  
Mitochondrial Coi Gene ◽  
Genetic Distinctiveness

Ten species, including four new species, of the chewing louse genus Forficuloecus Conci, 1941, are recognized from Australasian parrots, and a key is given for their identification. The new species and their type hosts are: F. cameroni ex the Red-winged Parrot, Aprosmictus erythropterus (J.F. Gmelin, 1788); F. banksi ex the Mulga Parrot, Psephotus varius Clark, 1910; F. wilsoni ex the Northern Rosella, Platycercus venustus (Kuhl, 1820); and F. josephi ex the Bourke's Parrot, Neopsephotus bourkii (Gould, 1841). Partial sequences of the mitochondrial COI gene support the genetic distinctiveness of these new species.

Are Tetranychus macfarlanei Baker & Pritchard and Tetranychus malaysiensis Ehara (Acari: Tetranychidae) one species? Morphological and molecular evidences for synonymy between these two spider mite species and a note on invasiveness of T. macfarlanei on okra and eggplant in India

2017 ◽  
Vol 22 (4) ◽  
pp. 467
Author(s):  
Mahran Zeity ◽  
Nagappa Srinivas ◽  
Chinnamade Channegowde Gowda
Keyword(s):  
Spider Mite ◽  
Morphological Characters ◽  
Molecular Data ◽  
Mite Species ◽  
Coi Gene ◽  
High Similarity ◽  
Mitochondrial Coi ◽  
Mitochondrial Coi Gene ◽  
High Degree ◽  
Degree Of Similarity

Study of morphological characters of Tetranychus macfarlanei Baker & Pritchard and Tetranychus malaysiensis Ehara revealed high similarity by comparing all the important characters in addition to the characters pointed out by Ehara to separate those two species. Molecular phylogeny of seven Indian populations of T. macfarlanei and one population of T. malaysiensis from Philippines along with few distantly related species of Tetranychus was attempted. High degree of similarity between these two species at mitochondrial COI gene (96%) as well as ITS2 (rDNA) (96–99%) region was evident. Based on both morphological features and molecular data, T. malaysiensis is proposed as a junior synonym of T. macfarlanei based on ICZN’s law of priority. Also more female characters are prompted in this study to distinctly discriminate T. macfarlanei from its most resembling species, Tetranychus ludeni Zacher. Tetranychus macfarlanei has emerged as a pest of several cultivated crop plants in India. 

A new species of Cyrtodactylus (Squamata: Gekkonidae) from Ninh Thuan Province, southern Vietnam

Zootaxa ◽  
2021 ◽  
Vol 4999 (1) ◽  
pp. 58-76
Author(s):  
Quyen Hanh Do ◽  
TRUNG MY PHUNG ◽  
HANH THI NGO ◽  
MINH DUC LE ◽  
THOMAS ZIEGLER ◽  
...  
Keyword(s):  
New Species ◽  
Phylogenetic Analyses ◽  
Coi Gene ◽  
Unique Combination ◽  
Mitochondrial Coi ◽  
Southern Vietnam ◽  
Mitochondrial Coi Gene ◽  
Morphological Differences ◽  
Dorsal Pattern ◽  
A New Species

A new species of the Cyrtodactylus irregularis group is described from Ninh Thuan Province, southern Vietnam based on molecular divergence and morphological differences. Cyrtodactylus orlovi sp. nov. is distinguished from the remaining Indochinese bent-toed geckos by having the unique combination of the following characters: size medium (SVL 61.0–77.7 mm); dorsal tubercles in 16–20 irregular rows; 36–39 ventral scale rows; precloacal pores absent in females, 5 or 6 in males, in a continuous row; femoral pores absent; 3–8 enlarged femoral scales; postcloacal spurs 1 or 2; lamellae under toe IV 16–19; a continuous neckband; a highly irregular transverse banded dorsal pattern; the absence of transversely enlarged median subcaudal scales. In phylogenetic analyses, the new species was revealed to be the sister taxon to a clade consisting of Cyrtodactylus cattienensis and the most recently described species from Vietnam, C. chungi, with 12.1–12.4% and 11.7 % pairwise genetic divergence from the two species, respectively, based on a fragment of the mitochondrial COI gene.  

scholarly journals Genetic Diversity and Population Structure of Metaphire vulgaris Based on the Mitochondrial COI Gene and Microsatellites

2021 ◽  
Vol 12 ◽  
Author(s):  
Yu Fang ◽  
Jie Chen ◽  
Honghua Ruan ◽  
Nan Xu ◽  
Ziting Que ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Coi Gene ◽  
Small Scale ◽  
The Novel ◽  
Mitochondrial Coi ◽  
Allele Number ◽  
Medicinal Value ◽  
Mitochondrial Coi Gene ◽  
Data Content ◽  
Genetic Structures

The earthworm species Metaphire vulgaris (a member of the Clitellata class) is widely distributed across China, and has important ecological functions and medicinal value. However, investigations into its genetic diversity and differentiation are scarce. Consequently, we evaluated the genetic diversity of five populations of M. vulgaris (GM, HD, NYYZ, QDDY, and QDY) in Yancheng, China via the mitochondrial COI gene and the novel microsatellites developed there. A total of nine haplotypes were obtained by sequencing the mitochondrial COI gene, among which NYYZ and QDDY populations had the greatest number of haplotypes (nh = 5). Further, the nucleotide diversity ranged from 0.00437 to 0.1243. The neighbor-joining trees and the TCS network of haplotypes indicated that earthworm populations within close geographical range were not genetically isolated at these small scale distances. Results of the identification of microsatellite molecular markers revealed that the allele number in 12 microsatellite loci ranged from 4 to 13. The observed heterozygosity ranged from 0.151 to 0.644, whereas the expected heterozygosity ranged from 0.213 to 0.847. The polymorphism data content of most sites was >0.5, which indicated that the designed sites had high polymorphism. Structural analysis results indicated that GM, HD, and NYYZ had similar genetic structures across the five populations. The Nei’s genetic distance between HD and NYYZ populations was the smallest (Ds = 0.0624), whereas that between HD and QDY populations was the largest (Ds = 0.2364). The UPGMA tree showed that HD were initially grouped with NYYZ, followed by GM, and then with QDDY. Furthermore, cross-species amplification tests were conducted for Metaphire guillelmi, which indicated that the presented markers were usable for this species. This study comprised a preliminary study on the genetic diversity of M. vulgaris, which provides basic data for future investigations into this species.

New species of Sargassum-boring Limnoria Leach, 1814 (Crustacea, Isopoda, Limnoriidae) from Japan

Zootaxa ◽  
2021 ◽  
Vol 4970 (1) ◽  
pp. 119-130
Author(s):  
HIROKI YOSHINO ◽  
YURIKO KAMBARA ◽  
SHOTA KAJIWARA ◽  
TAKESHI A. OHSAWA
Keyword(s):  
New Species ◽  
The Other ◽  
Coi Gene ◽  
Congeneric Species ◽  
Japanese Species ◽  
Mitochondrial Coi ◽  
Chiba Prefecture ◽  
Mitochondrial Coi Gene ◽  
Mandibular Palp ◽  
Coi Sequences

A new marine Sargassum-boring species of Limnoria (Limnoriidae) is described on the basis of specimens obtained at Kamogawa-shi, Chiba Prefecture, Japan. Limnoria aspera sp. nov. shares a reduced mandibular palp to a seta, algal-feeding, and the clavate shaped epipod of the maxilliped with the other species of non-mandibular-palp group. L. aspera sp. nov. differs morphologically from the congeneric species by secondary unguis of pereopods and unique carinae of pleonite 5 and pleotelson. We describe the sequences of the mitochondrial COI gene and the nuclear 28S rDNA gene. L. aspera sp. nov. differs by 14.2–18.0% in p-distance based on COI sequences from other Japanese species, L. furca and L. nagatai. 

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