Henricia Species Research Articles

Complete Mitochondrial Genomes and Phylogenetic Analysis of Genus Henricia (Asteroidea: Spinulosida: Echinasteridae).

The genus Henricia is known to have intraspecific morphological variations, making species identification difficult. Therefore, molecular phylogeny analysis based on genetic characteristics is valuable for species identification. We present complete mitochondrial genomic sequences of Henricia longispina aleutica, H. reniossa, and H. sanguinolenta for the first time in this study. This study will make a significant contribution to our understanding of Henricia species and its relationships within the class Asteroidea. Lengths of mitochondrial genomes of the three species are 16,217, 16,223, and 16,194 bp, respectively, with a circular form. These genomes contained 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and a D-loop. The gene order and direction aligned with other asteroid species. Phylogenetic relationship analysis showed that our Henricia species were in a monophyletic clade with other Henricia species and in a large clade with species (Echinaster brasiliensis) from the same family. These findings provide valuable insight into understanding the phylogenetic relationships of species in the genus Henricia.

Morphological Description and Molecular Analysis of Newly Recorded Asteroid, Henricia djakonovi Chichvarkhin, 2017 (Asteroidea: Spinulosida: Echinasteridae), from Dokdo Island, Korea

We recently collected the samples of Henricia from adjacent waters of Dokdo Island, Korea, using trimix SCUBA diving. Based on a combined result of morphological and molecular analysis, we identified our specimen as Henricia djakonovi Chichvarkhin, 2017, which is newly recorded in Korea. Morphologically, H. djakonovi has crescent abactinal plates bearing numerous pillar-shaped abactinal spines with a droplet-like apical tip. Moreover, molecular analysis based on the mitochondrial COI gene occurred that clearly distinguished H. djakonovi from other species of Henricia in the pairwise genetic distance and maximum likelihood analysis. Accordingly, 15 species of Henricia are recorded in Korean fauna, including H. djakonovi.

Two new deep-sea species of the genus Henricia (Asteroidea: Spinulosida: Echinasteridae) from Japanese waters

Two new deep-sea Henricia species, Henricia margarethae n. sp. and Henricia fragilis n. sp. are described from Sagami Bay and the Ogasawara Islands in Japan. The two new species show an affinity with eight congeners in having multiple furrow spines and abactinal papular areas which are larger than surrounding plates. The two species described herein are characterized by the arrangement of abactinal pseudopaxillae, the arrangement of abactinal papulae, the shape and arrangement of abactinal spines, the length of intermarginal and ventrolateral series, and the armament of superomarginal, inferomarginal, and adambulacral plates.

Newly recorded sea star <i>Henricia oculata</i> (Asteroidea: Spinulosida: Echinasteridae) in the East Sea, Korea

Henricia specimens were collected using fishing nets from the East Sea of Korea. The specimens were identified as Henricia oculata Pennant, 1777, belonging to the family Echinasteridae of the order Spinulosida. This species can be distinguished from other Henricia species by broad arms (R/r=4-4.1), rough skin, a thick arm base, three to nine minute delicate abactinal spines, and inferomarginal plates reniform in shape. This species superficially resembles H. pachyderma in its body size and wide papular areas but differs mainly in the number of papulae and abactinal spines, and the shape and arrangement of the inferomarginal plates. To date, two genera of Echinasteridae, Aleutihenricia and Henricia, with a total of 13 species, have been reported in Korea. The morphological characteristics of H. oculata are described, and photographs are provided.

A new species of the genus Henricia (Asteroidea, Spinulosida, Echinasteridae) from South Korea.

A new species of the genus Henricia Gray, 1840 that belongs to the family Echinasteridae is described from South Korea. Henricia epiphysialissp. nov. has epiphyseal ossicles at the ends of the abactinal and lateral plates, and the abactinal and lateral spines form a hooked crown. The partial sequence of the mitochondrial COXI gene (537 bp) of H. epiphysialissp. nov. was obtained, and the new species was morphologically and genetically compared with other related Henricia species.

New record of a sea star, <i>Henricia perforata</i> (Asteroidea: Spinulosida: Echinasteridae), in the East Sea, Korea

Sea stars were collected from the adjacent waters of Jukbyeon and Jumunjin, Korea, using fishing nets at depths of 70-100 m. The specimens were identified as Henricia perforata (O.F. Muller, 1776) in the family Echinasteridae and order Spinulosida, with worldwide species distribution. H. perforata can be distinguished from some morphologically related Henricia species by its long, slender, and pointed adambulacral spines. The abactinal skeleton of H. perforata has wide papular areas resembling those of H. pachyderma, but the former has more papulae (two to seven). Previously, two genera of Echinasteridae, Aleutihenricia and Henricia, with a total of 12 echinasterid species, have been reported in Korea. The morphological characteristics of H. perforata are described and photographs are provided.

New record of a sea star of genus <i>Henricia</i> (Asteroidea: Spinulosida: Echinasteridae) from Jeju Island, Korea

An asteroid specimen that belongs to the genus Henricia was collected from the waters near Ongpo harbor, Jeju Island using fishing net on 24 January 2017. The specimen was identified as Henricia anomala Hayashi, 1973, which belongs to the family Echinasteridae and order Spinulosida. Henricia anomala was first described by Hayashi, 1973, who captured it from Sagami Bay at a depth of 110-116 m. This species can be distinguished from other Henricia species by short arms (R/r=4), abactinal spines lining the abactinal plates and bearing about two to five spinelets, closely meshed abactinal skeleton, composed of small rod-like and subtriangular plates, a narrow papular area containing one or two papulae, and adambulacral armature composed of five to seven bluntly pointed spinelets. This is the first report of Henricia anomala in Korea.

Henricia spp. (Echinodermata: Asteroidea: Echinasteridae) of the White Sea: morphology, morphometry, and synonymy

Though sea stars of the genus Henricia Gray, 1840 are widely used in biological studies, their species diversity in the Arctic is poorly understood. We conducted a taxonomic revision of the genus Henricia from the White Sea and examined 381 specimens of Henricia sea stars deposited in the collection of the Zoological Institute of the Russian Academy of Sciences (St. Petersburg), the type collection founded by A.M. Djakonov, and our own collection. Following the 1987 study by F.J. Madsen and the 1950 study by A.M. Djakonov, we identified six species in the White Sea: Henricia eschrichti (J. Müller and Troschel, 1842), Henricia perforata (O.F. Müller, 1776), Henricia scabrior (Michailovskij, 1903), Henricia solida Djakonov, 1950, Henricia sanguinolenta (O.F. Müller, 1776), and Henricia pertusa (O.F. Müller, 1776). Updated descriptions, identification keys, and distribution data of these species are provided. Statistical analysis based on the set of individual characters confirmed the validity of the species H. scabrior. Synonymy of Henricia species according to the 1950 study by A.M. Djakonov and the 1987 study by F.J. Madsen is discussed.

A new record of sea star genus Henricia (Asteroidea: Spinulosida: Echinasteridae) from Jeju Island, Korea

Some asteroid specimens of genus Henricia were collected at a depth of 50-90 m near waters of Moseulpo, Jeju Island, Korea using fishing nets on September 2015. The specimens were identified as Henricia elachys Clark and Jewett, 2010 belonging to the family Echinasteridae of order Spinulosida. This small species can be distinguished from other Henricia species by short arms, moderately inflated arm base, and slightly broad disk. The morphological characteristics of this species were described with illustrations. Up to date, there are nine species of genus Henricia reported in Korean fauna.

The molecular phylogeny of the sea star Echinaster (Asteroidea: Echinasteridae) provides insights for genus taxonomy

AbstractIn this study, we used sequences of two mitochondrial genes, cytochrome c oxidase I (COI) and 16S rRNA, and one nuclear gene, 28S rRNA, to test the monophyly of the sea star genus Echinaster, and understand the phylogenetic relationships among species and subgenera within this genus. Phylogenetic analyses based on Bayesian inference and maximum likelihood methods revealed three clades with high values of genetic divergence among them (K2P distances for COI over 23%). One of the clades grouped all Echinaster (Othilia) species, and the other two clades included Echinaster (non‐Othilia) species and Henricia species, respectively. Although the relationships among Henricia, Othilia, and Echinaster could not be completely clarified, the Othilia clade was a well‐supported group with shared diagnostic morphological characters. Moreover, the approximately unbiased test applied to the phylogenetic reconstruction rejected the hypothesis of the genus Echinaster as a monophyletic group. According to these results, we suggest the revalidation of Othilia as a genus instead of a subgenus within Echinaster. Our study clarifies important points about the phylogenetic relationships among species of Echinaster. Other important systematic questions about the taxonomic classification of Echinaster and Henricia still remain open, but this molecular study provides bases for future research on the topic.

Records of the genus Henricia Gray, 1840 (Echinodermata: Asteroidea: Echinasteridae) from Chinese waters

Eight species and three subspecies of Henricia Gray, 1840 from Chinese waters are reported: H. arcystata Fisher, H. aspera robusta Djakonov, H. densispina (Sladen), H. exigua Hayashi, H. leviuscula leviuscula (Stimpson), H. leviuscula spiculifera (H.L.Clark), H. ohshimai Hayashi, H. pacifica Hayashi, H. regularis Hayashi, six of which are reported for the first time from Chinese waters. A key to Chinese species of Henricia and photos are provided. Species diversity of echinoderms in China seas is briefly discussed.