Chondrochelia Gutu, 2016 (Crustacea, Peracarida, Tanaidacea, Leptocheliidae) from North America: new species, redescription and distribution using morphological and molecular data.

Until now, four species of the genus Chondrochelia Gutu, 2016 have been recorded from America. Using morphological and molecular data, we were able to recognize and describe two new species, Chondrochelia caribensis sp. nov. from the Mexican Caribbean and Chondrochelia winfieldi sp. nov. from the Gulf of Mexico. We found significant genetic divergence values between species based on the nucleotide sequences of cytochrome oxidase subunit I to support the morphological data. Also, the range of distribution of two species: Chondrochelia mexicana (Jarquín-González, García-Madrigal & Carrera-Parra, 2015) and Chondrochelia ortizi (Jarquín-González, 2016), were expanded within their described geographic regions. In contrast, the supposed distribution of the Brazilian C. dubia in the Mexican Caribbean and the Gulf of Mexico was rejected. Additionally, Chondrochelia algicola (Harger, 1878) was redescribed based upon type material. Minute details and ornamentation of some structures of three species were examined using SEM.

Phylogeny of Microphthalminae Hartmann-Schröder, 1971, and revision of Hesionella Hartman, 1939, and Struwela Hartmann-Schröder, 1959 (Annelida, Errantia).

Microphthalminae Hartmann-Schröder, 1971 was proposed in Hesionidae to include Microphthalmus and Hesionides; however, the affinities of these genera to other members of Hesionidae have been debated, and some authors have concluded they do not belong in Hesionidae. Herein, based on morphological characters, a phylogenetic analysis of the subfamily and some other similar poorly-known genera, with an uncertain position in Hesionidae was performed to clarify their affinities. Our results indicate that Microphthalminae, as currently delimited, is paraphyletic. The inclusion of Struwela, Uncopodarke, and Westheideius, a new genus, as well as the recognition of Fridericiella are proposed to meet the requirement of monophyly; and as result of this, the elevation in rank to the family level is herein presented. Furthermore, the type species for Hesionella and Struwela are redescribed, and a new species in the latter is described. A key to identify microphthalmid genera is also included.

Redescription of Hargeria rapax (Harger, 1879) and description of H. chetumalensis a new species from the Mexican Caribbean (Crustacea, Peracarida, Tanaidacea, Leptocheliidae) based upon morphological and molecular evidence.

Until now, Hargeria was considered a monospecific leptocheliid genus, with the species Hargeria rapax considered a taxon with a wide distribution, from the Northwestern Atlantic to the Mexican Caribbean. Herein, after a detailed revision of type and topotype materials and specimens collected from the Mexican Caribbean, a new species H. chetumalensis sp. nov. is described, and the redescription of H. rapax is provided. Also, we found a significant genetic divergence between the two species based on the nucleotide sequences of cytochrome oxidase subunit I, which support the morphological data. The morphological features used to recognize both species are also adequate to link males, females, and juvenile stages, although these species have a high intraspecific polymorphism.

New Phylogenetic Analysis of Paraprionospio Caullery (Polychaeta: Spionidae), with Description of a New Species from the Gulf of Mexico.

Víctor H. Delgado-Blas and Luis F. Carrera-Parra (2018) A cladistic analysis of Paraprionospio was conducted based on the revision of some type materials and the original descriptions of some species. The phylogenetic reconstruction of Paraprionospio using parsimony analysis of 45 morphological characters yielded one most parsimonious tree (CI = 0.45, RI = 0.54). Herein, thirteen Paraprionospio species were considered to be valid, and one new species was described: Paraprionospio pinnata (Ehlers, 1901), P. inaequibranchia (Caullery, 1914), P. africana (Augener, 1918), P. alata (Moore, 1923), P. treadwelli (Hartman, 1951), P. lamellibranchia Hartman, 1974, P. coora Wilson, 1990, P. tamaii Delgado-Blas, 2004, P. yokoyamai Delgado-Blas, 2004, P. cordifolia Yokoyama, 2007, P. oceanensis Yokoyama, 2007, P. patiens Yokoyama, 2007, P. cristata Zhou, Yokoyama and Li, 2008, and P. dibranchiata sp. nov. This species is characterized by having two pairs of branchiae on chaetigers 1-2, the first pair pinnate with few pinnules, the second one cirriform; and with a long filament at the base of third notopodial lamella on chaetiger 3. Also, P. alata, P. treadwelli and P. inaequibranchia were redescribed based upon type material, and several morphological features were included to clarify the taxonomic status of P. treadwelli, P. tamaii and P. yokoyamai, which were previously considered synonyms of P. alata. A taxonomic key to all Paraprionospio species is provided.

Revision of Marphysa de Quatrefages, 1865 and some species of Nicidion Kinberg, 1865 with the erection of a new genus (Polychaeta: Eunicidae) from the Grand Caribbean.

Nine species of Marphysa from the Grand Caribbean Region are recognized and described based on the type and non-type specimens. One species is formally described as new: M. emiliae n. sp., and one is re-established as a valid species: M. fragilis Treadwell, 1911. The diagnosis of Nicidion Kinberg, 1865 is restricted based on novel features of the maxillary apparatus. Nicidion angeli (Carrera-Parra & Salazar-Vallejo, 1998) is redescribed, and two species that previously belonged to Marphysa, are transferred to Nicidion: N. longula (Ehlers, 1887) n. comb. and N. obtusa (Verrill, 1900) n. comb.. A new genus Treadwellphysa n. gen. is proposed to include those species having a newly described type of chaetae named spinifalcigers (exhibiting a mixture of falciger and spiniger blades), the base of maxillae II with a small elevation, and the ventral cirri with swollen base as transverse welt with short digitiform tip. Treadwellphysa n. gen. includes a new species, T. yucatanensis n. sp. and three other species previously included in Marphysa: T. amadae (Fauchald, 1977) n. comb., T. languida (Treadwell, 1921) n. comb., and T. veracruzensis (de León-González & Díaz-Castañeda, 2006) n. comb. Some morphological features are evaluated to clarify their variability with respect to specimen size. A key to Eunicidae genera, and keys to species of Marphysa and Treadwellphysa n. gen. from the Grand Caribbean region are given.

Redescription of Alitta succinea (Leuckart, 1847) and reinstatement of A. acutifolia (Ehlers, 1901) n. comb. based upon morphological and molecular data (Polychaeta: Nereididae).

The nereidid worm Alitta succinea (Leuckart, 1847), described from Western Germany, has been considered by some authors as a widespread and alien invasive species, or else as a group of morphologically indistinguishable species. Neither idea has yet been supported by critical taxonomic revisions of relevant material. Most characterizations of A. succinea were based upon a mixture of morphological features from specimens from the type locality and from other regions. Moreover, four species described from America are considered junior synonyms of A. succinea, including Nereis acutifolia Ehlers, 1901, described from the eastern tropical Pacific. The type material of the latter species has not been reviewed since its description. We re-examined type and topotype materials of A. succinea and N. acutifolia including atokous and epitokous specimens. In addition, newly collected specimens were used to evaluate genetic divergence between both species using the mitochondrial gene COI. Alitta succinea is redescribed from type material and specimens from Germany. We rejected the recent placement of the species in Neanthes and we transferred it to Alitta. Further, we refuse the synonymy of N. acutifolia with A. succinea due to morphological and molecular differences. Consequently, we regard Alitta acutifolia n. comb. as a valid species, and the supposed introduction and the alien status of A. succinea along the Mexican and Central American Pacific shores are rejected.

Reinstatement of three species of the Marphysa sanguinea complex (Polychaeta: Eunicidae) from the Grand Caribbean Region.

As part of a study on Marphysa de Quatrefages, 1865 from the Grand Caribbean, three species regarded as junior synonyms of M. sanguinea (Montagu, 1913) were studied to clarify their taxonomic status. The examination of type and additional materials collected in the southern Gulf of Mexico and the Mexican Caribbean regions, allowed us to clarify that M. acicularum Webster, 1884, M. nobilis Treadwell, 1917 and M. viridis Treadwell, 1917 are distinct species. Therefore, the three species were redescribed and some important morphological features such as maxillary apparatus, shape of parapodial lobes, shape of ventral cirri and pectinate chaetae, among others, were described and evaluated. Furthermore, we consider that previous records of M. sanguinea for the Grand Caribbean are doubtful and it is necessary to reassess those specimens to clarify their taxonomic identity.

First record of the genus Kuwaita (Annelida: Lumbrineridae) in Europe with the description of a new species and new ultramorphological data for the genus.

A new species of the genus Kuwaita Mohammad, 1973, collected intertidally from a northern Spain estuary (Bay of Biscay), is described. Kuwaita hanneloreae sp. nov. constitutes the first evidence of this genus in European waters and is characterised by: prostomium with three small antennae protruding from nuchal fold, lack of eyes; simple multidentate hooded hooks with long hood in anterior chaetigers, and short hood in posterior ones with well defined proximal and distal teeth with several teeth between them; posterior chaetigers with very small nephridial papillae; branchiae reduced to little knobs in posterior parapodia; maxillary apparatus with five pairs of maxillae, MIII bidentate with distal tooth bigger than proximal one. We present brief notes on its ecology and remarks on the presence and ultrastructure of a notopodial sense organ newly recorded for the genus. Furthermore, an updated key of the genus Kuwaita is included.

Polychaete species (Annelida) described from the Philippine and China Seas.

The South China and Philippine Seas are among the most diverse regions in the Western Pacific. Although there are several local polychaete checklists available, there is none comprising the whole of this region. Presented herein is a comprehensive list of the original names of all polychaete species described from the region. The list contains 1037 species, 345 genera and 60 families; the type locality, type depository, and information regarding synonymy are presented for each species. 

A new species of the rare endoparasitic copepod Entobius (Copepoda: Entobiidae) from Mexico with a key to the species of the genus.

Abstract: In a study of the benthic polychaete fauna of the southern Gulf of Mexico and the Caribbean Sea, several specimens of the terebellid polychaete Scionides reticulata (Ehlers) were found to host endoparasitic copepods that represent an undescribed species of the rare cyclopoid genus Entobius Dogiel, 1948. The new species, E. scionides sp. n., can be distinguished from its congeners by a combination of characters including a genital region without constrictions, three-segmented antennules, a reduced antenna with a blunt terminal process, reduced ornamentation of endopods of legs 1-4 and its relatively small size (2.3-2.7 mm). It is the smallest species of the genus. Comments on immature females are also provided, but males of this species remain unknown. It has a high prevalence (53%) in populations of the terebellid S. reticulata in the southern Gulf of Mexico, but it is absent from the Caribbean. This is the first occurrence of this copepod genus in the Americas. The finding of the new species of Entobius in S. reticulata confirms the strict specificity of most members of the genus and expands the host range of this copepod genus. A key for the identification of the species of Entobius is provided.

Giant Eunicid Polychaetes (Annelida) in shallow tropical and temperate seas

Some species of Eunice might reach giant size, often being longer than 2m, and they are known from tropical and temperate seas. Despite their large size and recent internet notoriety, there remain some taxonomic problems in large-sized eunicids, especially since original descriptions were brief and type materials are often missing. As a mean to encourage the solution of this situation, we review the historical progress in the taxonomy of the group, including some comments on generic and specific delineation, and recommend some critical steps to solve the current confusion. These ideally would include collecting in type localities, evaluate ontogenetic morphological changes, and generate some molecular analysis to complement the morphological approach. Rev. Biol. Trop. 59 (4): 1463-1474. Epub 2011 December 01.

Algunas species de Eunice pueden alcanzar tamaño gigantesco, a menudo sobrepasan los 2m de largo, y se conocen de mares tropicales y templados. A pesar de su gran tamaño y de su reciente notoriedad en Internet, todavía hay problemas taxonómicos entre los eunícidos gigantes, especialmente dado que las descripciones originales fueron breves y a menudo se carece de materiales tipo. Para incentivar la solución del problema, revisamos el desarrollo histórico de la taxonomía del grupo y se incluyen algunos comentarios sobre la delineación de los géneros y de las especies y recomendamos algunos pasos críticos para alcanzar este fin. Idealmente, esto incluiría recolectar en las localidades tipo, evaluar cambios morfológicos durante la ontogenia y generar algunos análisis moleculares para complementar el enfoque morfológico.

Giant eunicid polychaetes (Annelida) in shallow tropical and temperate seas.

Some species of Eunice might reach giant size, often being longer than 2m, and they are known from tropical and temperate seas. Despite their large size and recent internet notoriety, there remain some taxonomic problems in large-sized eunicids, especially since original descriptions were brief and type materials are often missing. As a mean to encourage the solution of this situation, we review the historical progress in the taxonomy of the group, including some comments on generic and specific delineation, and recommend some critical steps to solve the current confusion. These ideally would include collecting in type localities, evaluate ontogenetic morphological changes, and generate some molecular analysis to complement the morphological approach.