scholarly journals A morphological, phylogenetic and phylogeographic reappraisal of the land crabs Gecarcinus quadratus De Saussure, 1853, and G. lateralis Fréminville in Guérin, 1832 (Decapoda: Gecarcinidae). Are they different species?

Zootaxa ◽  
2021 ◽  
Vol 5048 (2) ◽  
pp. 215-236
Author(s):  
IA ATZIMBA TOLEDANO-CARRASCO ◽  
JOSÉ LUIS VILLALOBOS ◽  
FERNANDO ÁLVAREZ
Keyword(s):  
Pacific Coast ◽  
Genetic Difference ◽  
Average Distance ◽  
Atlantic Coast ◽  
Valid Species ◽  
Mexican Pacific ◽  
Mitochondrial Coi ◽  
The Pacific ◽  
Land Crabs ◽  
The Status

Land crabs of the genus Gecarcinus are distributed along both versants of the American continent. At some point four species were recognized: G. lateralis, G. nobilii, G. quadratus, and G. ruricola. Taxonomically, several authors have tried to differentiate Gecarcinus lateralis from the Atlantic coast and G. quadratus from the Pacific coast. Because morphologic characters used showed high intra-population variability, identification were very difficult. Consequently, these two species have occasionally been considered synonyms. To establish the degree of genetic difference between them a molecular analysis was performed with both species, G. lateralis and G. quadratus, including Mexican Pacific and Atlantic specimens, using the mitochondrial COI and 16S genes. The maximum clade credibility and maximum likelihood trees showed two clades with high support values, one corresponding to the Gulf of Mexico population and the other one to the Pacific coast population, with a genetic distance of 6.1%. The within-clade average distance for the Atlantic populations (G. lateralis) was 1.1% and 0.2% for those of the Pacific coast (G. quadratus). This supports the status of G. quadratus as a valid species, not as a synonym of G. lateralis. The estimated time of divergence between both species ranged between 2.3 to 4.3 million years, coinciding with the proposed closure of the Isthmus of Panama. Morphologically, some populations show high variability in somatic characters, whereas sexual appendices of males of both species showed very little variation. Color in life, shape of sternite 3, and shape and degree of coverage of the abdomen of thoracic sternites, in both sexes, are traits that can be used to differentiate both species.  

scholarly journals Two new species of Microcotyle (Monogenea: Microcotylidae) on intertidal fish from the south Pacific coast

2020 ◽  
Vol 54 (3) ◽  
pp. 283
Author(s):  
Gabriela Muñoz ◽  
Mario George-Nascimento
Keyword(s):  
New Species ◽  
Pacific Coast ◽  
Valid Species ◽  
Base Pairs ◽  
Central Chile ◽  
South Central ◽  
The Pacific ◽  
The Family ◽  
Two New Species ◽  
Intertidal Fish

Microcotyle is one of the most diverse and controversial genera within the family Microcotylidae. To date, 131 species have been described in Microcotyle; however, more than half have been transferred to other genera, and several others have poor descriptions. Therefore, less than half of all Microcotyle species may be considered valid. In Chile, two species have been recognized, and unidentified Microcotyle have been found on several littoral fish, but there has been no effort to properly identify them. In this study, two new species of Microcotyle are taxonomically described from intertidal fish of the central (33°S) and south-central (36°S) regions of Chile. In this study, Microcotyle sprostonae n. sp. (collected mainly from Scartichthys viridis in central Chile) and M. chilensis n. sp. (collected mainly from Calliclinus geniguttatus in south-central Chile) were identified based on morphological and molecular analyses (ITS2 and 18S genes). Both species of Microcotyle principally differed from one another and from other valid species in the number of testes and clamps. The two new species also differed from one another by one base pair in the ITS2 and 18S genes and differed from other species of Microcotyle by several base pairs of both genes. Intertidal fish are mostly endemic to the Pacific coast of South America, and they have a limited geographical distribution that does not overlap with the type hosts of other Microcotyle species. Therefore, the two new species described here are distinguished from other congeneric species by morphological, genetic, and biological characteristics.

TWO NEW MEXICAN ISOTOGASTRURA (COLLEMBOLA: ISOTOGASTRURIDAE)

1998 ◽  
Vol 130 (2) ◽  
pp. 195-199 ◽  
Author(s):  
José G. Palacios-Vargas ◽  
Jean-Marc Thibaud
Keyword(s):  
New Species ◽  
Pacific Coast ◽  
Atlantic Coast ◽  
New Mexican ◽  
The Pacific ◽  
Two New Species

AbstractTwo new species of Isotogastrura, one from the Pacific coast and one from the Atlantic coast, are described: Isotogastrura ahuizotli sp.nov. and Isotogastrura veracruzana sp.nov. A key for the five species known at present is included.

Taxonomy of Centropomus Lacépède, 1802 (Perciformes: Centropomidae), with focus on the Atlantic species of the genus

Zootaxa ◽  
2021 ◽  
Vol 4942 (3) ◽  
pp. 301-338
Author(s):  
JESSÉ MIRANDA DE FIGUEIREDO-FILHO ◽  
ALEXANDRE P. MARCENIUK ◽  
ANDERSON FEIJÓ ◽  
RAQUEL SICCHA-RAMIREZ ◽  
GIOVANA S. RIBEIRO ◽  
...  
Keyword(s):  
Geometric Morphometrics ◽  
Pacific Coast ◽  
Atlantic Coast ◽  
Lateral View ◽  
Cytochrome C Oxidase I ◽  
Linear Measurements ◽  
Molecular Analyses ◽  
Needed Information ◽  
The Pacific ◽  
Pacific Species

Centropomus Lacépède, 1802 comprises 13 species of the fishes popularly knows as snooks, distributed in both Atlantic and Pacific coasts of America. Despite several studies on the group, conflicting taxonomic classifications still exist, including overlapping diagnostic characters, rendering species diagnoses extremely difficult. Herein, we review the taxonomy of Centropomus to elucidate species identities, redefine their diagnoses and to assess interspecific relationships based on the examination of 376 specimens. The study included complementary approaches, as analyses of external morphologic characters, linear and geometric morphometrics, and molecular analyses. Forty-nine characters were used for external morphology, 17 discrete plus 32 linear measurements. Shape and size were analyzed through geometric morphometrics of 185 specimens in lateral view. Partial sequences of the gene cytochrome c oxidase I were obtained for 129 specimens representing 11 species. Based on the consistent results retrieved from the morphologic and molecular analyses, we recognized six species of Centropomus from the Atlantic coast (C. ensiferus, C. irae, C. parallelus, C. pectinatus, C. poeyi and C. undecimalis). Centropomus mexicanus is treated as a junior synonym of C. parallelus. Six species from the Pacific coast are also tentatively recognized (C. armatus, C. medius, C. nigrescens, C. robalito, C. unionensis, and C. viridis), however further studies on the Pacific species are still needed. Information on type material, diagnosis, distribution, and taxonomic comments are provided for each species. An identification key to the species of Centropomus is presented. 

A revision of the genus Mycale (Poecilosclerida: Mycalidae) from the Mexican Pacific Ocean

2010 ◽  
Vol 79 (4) ◽  
pp. 165-191 ◽  
Author(s):  
José L. Carballo ◽  
José A. Cruz-Barraza
Keyword(s):  
Pacific Ocean ◽  
Pacific Coast ◽  
Type Material ◽  
Mexican Pacific ◽  
East Pacific ◽  
The Pacific ◽  
Taxonomic Studies ◽  
Species Descriptions ◽  
First Time

Knowledge about the sponge fauna from the Mexican Pacific Ocean has increased substantially in recent years, but most of these modern taxonomic studies have been focused on hadromerids. The aim of this study was to contribute to the knowledge of the order Poecilosclerida. At present, seven species of Mycale have been described or recorded from the Pacific coast of Mexico, but only three of them are considered valid: M. contax, M. cecilia and M. aff. magnirhaphidifera. After a revision of the material collected during the last eight years throughout the East Pacific coast of Mexico, along with the type material, and the literature available, eight species of Mycale are considered valid, three of them; M. magnitoxa sp. nov., M. dickinsoni sp. nov., and M. ramulosa sp. nov., are proposed as new to science. In addition, M. adhaerens is reported for the first time from the Mexican Pacific Ocean. Another Mycale-species that was identified was M. psila, which constitutes its seconLamberd record for the Mexican Pacific Ocean. The systematic, distribution and detailed species descriptions are based on newly collected material and previous descriptions from the literature.

New records of benthic hydroids (Cnidaria: Hydrozoa) from the coast of Oaxaca, Mexico

Zootaxa ◽  
2018 ◽  
Vol 4455 (3) ◽  
pp. 454 ◽  
Author(s):  
KARLA J. HUMARA-GIL ◽  
CHRISTOPHER CRUZ-GÓMEZ
Keyword(s):  
Pacific Coast ◽  
New Records ◽  
Mexican Pacific ◽  
Geographic Ranges ◽  
The Pacific

Hydroids of the Pacific coast of Mexico have been little studied. For the coast of Oaxaca, only five papers provide information on species of the region, with some records included in those publications being questionable. Seven species, Pennaria disticha, Clytia linearis, Clytia cf. gracilis, Obelia dichotoma, Ventromma halecioides, Dynamena crisioides and Tridentata turbinata, were discovered during the study and are reported herein. Of these species, Pennaria disticha and Tridentata turbinata are new records for the Mexican Pacific coast, and Clytia linearis and Ventromma halecioides are new records for Oaxaca. Geographic ranges of other hydroids, recorded in earlier studies, are expanded.

First record of Plakortis Schulze (Porifera: Homosclerophorida) from the Northeast Pacific coast, with the description of Plakortis albicans sp. nov.

Zootaxa ◽  
2005 ◽  
Vol 868 (1) ◽  
pp. 1 ◽  
Author(s):  
JOSÉ A. CRUZ-BARRAZA ◽  
JOSÉ L. CARBALLO
Keyword(s):  
Pacific Coast ◽  
First Record ◽  
Single Class ◽  
Mexican Pacific ◽  
Northeast Pacific ◽  
The Pacific ◽  
Drainage Canals ◽  
Cryptic Habitats ◽  
East Pacific Ocean ◽  
A New Species

A new species of Plakortis Schulze, 1880 from the Pacific coast of Mexico is described, which constitutes the first record of the Plakortis genus in the Northeast Pacific coast, and the first record of Homosclerophorida in the Mexican Pacific coast. Plakortis albicans sp. nov. is characterized by its white or ivory color, by a surface sculpted by subectosomic drainage canals, and by the morphological details of its skeleton, such as the presence of diods and triods in one single class, and a tangential alveolar ectosomal skeleton formed mostly by smaller diods. The only species known in the genus Plakortis from the East Pacific Ocean is Plakortis galapagensis Desqueyroux-Faúndez & van Soest, 1997, which differs from Plakortis albicans sp. nov. mainly by having diods in two distinct size classes. So far, P. albicans is only known in one locality (Mazatlán Bay), where it is relatively abundant in cryptic habitats such as under rock.

Redescription of Liopropoma aragai (Teleostei: Serranidae), with two new confirmed records of species of Liopropoma from Taiwan

Zootaxa ◽  
2019 ◽  
Vol 4702 (1) ◽  
pp. 60-72
Author(s):  
KEITA KOEDA ◽  
HIROSHI SENOU ◽  
CHIH-WEI CHANG ◽  
HSUAN-CHING HO
Keyword(s):  
Pacific Coast ◽  
Ryukyu Archipelago ◽  
Type Specimens ◽  
Okinawa Island ◽  
Diagnostic Characters ◽  
The Pacific ◽  
The Status ◽  
Voucher Specimens ◽  
Pacific Coast Of Japan ◽  
First Time

Liopropoma aragai Randall & Taylor 1988 is redescribed based on the holotype and non-type specimens from Japan and Taiwan. Diagnostic characters of the species and the status of Taiwanese specimens previously referred to L. aragai are reassessed. Liopropoma lemniscatum Randall & Taylor 1988, previously recorded only from the Pacific coast of Japan and the Ryukyu Archipelago, and L. lunulatum (Guichenot 1863), previously known from Okinawa Island (Japan), Guam, Réunion, Rarotonga and Tahiti, are redescribed, both being confirmed for the first time by voucher specimens from Taiwanese waters. A detailed description of each species and a key to Taiwan Liopropoma Gill 1861 is provided. 

Records of mud shrimps (Crustacea: Decapoda: Axiidea and Gebiidae) from Pacific Mexico

2013 ◽  
Vol 94 (2) ◽  
pp. 369-388 ◽  
Author(s):  
Manuel Ayón-Parente ◽  
Michel E. Hendrickx ◽  
Eduardo Ríos-Jara ◽  
José Salgado-Barragán
Keyword(s):  
Pacific Coast ◽  
Eastern Pacific ◽  
Western Atlantic ◽  
Mexican Pacific ◽  
The Pacific ◽  
First Time

A total of 75 specimens belonging to four species of thalassinoids were collected in the intertidal and estuarine zones of two localities along the Pacific coast of Mexico.Callianassa tabogensisis recorded for the first time in Mexico, and is transferred to the genusNeotrypaea. Material ofCallichirusis assigned toCallichirus seilacheriwith some doubts due to taxonomic problems related to this genus in the eastern Pacific.Neocallichiruscf.grandimana, an amphi-American species described for the western Atlantic and previously reported in Ecuador and along the Pacific coast of Panama and Colombia, is reported for the first time in Mexico.Upogebia dawsoniis recorded for the second time from the coast of Jalisco. An updated list of Axiidea and Gebiidea known from the Mexican Pacific is provided, including 35 species.

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