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Henricia perforata: (a, b, f, g) light microscopy and (c, d, e) scanning microscopy. (a, b) Abactinal view; (c) part of abactinal skeleton, note secondary plates that subdivide the meshes (white arrow); (d) abactinal spines from the basal arm; (e) part of abactinal skeleton with partially preserved integument and pseudopaxillae, note the secondary plate (white arrow); (f) part of abactinal side, note single papula (white arrow); (g) part of actinal side, inferomarginal spines arranged in rows are indicated by white arrows. Scale bars: (a, b) 1 cm; (c, e) 500 m; (d) 50 m; (f, g) 1 mm.
Source publication
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 Academ...
Contexts in source publication
Context 1
... External morphology -Body shape greatly variable (Figs. 4a, 4b). Arms sometimes tapering gradually from comparatively large base to blunt tip. In some specimens, disk smaller and arms cylindrical, usually stout, rarely slender. R/r ratio varying from 2.7 to 5.8. In largest specimen, R = 80 mm and r = 19 mm (R = 4.2r). Arm angles usually acute, with interbranchial depressions extending just up on ...
Context 2
... disk smaller and arms cylindrical, usually stout, rarely slender. R/r ratio varying from 2.7 to 5.8. In largest specimen, R = 80 mm and r = 19 mm (R = 4.2r). Arm angles usually acute, with interbranchial depressions extending just up on disk. Colour in life varying from lilac to purple and violet. Entire body covered with thick integument (Fig. ...
Context 3
... meshwork with relatively large meshes. Meshes in basal part of arm measuring 0.7-1.8 mm in length. Abactinal plates oval, four-lobed, each with a well-defined tubercle. Ends of abactinal plates often overlapping. Several small intermediate plates present in some large meshes, loose or connecting into group of secondary plates subdividing the mesh (Fig. 4c). Papulae in almost every mesh, single (Fig. 4f) or in groups of 2-4. Spines large, stout, with serrated, although slightly blunt distal ends (Fig. 4d), 0.3-0.7 mm in length. Spines grouped in pseudopaxillae, 3-8 spines in each, groups of 6-8 spines occurring rarely (Figs. 4e, 4f). Secondary (intermediate) plates bearing fewer spines ...
Context 4
... basal part of arm measuring 0.7-1.8 mm in length. Abactinal plates oval, four-lobed, each with a well-defined tubercle. Ends of abactinal plates often overlapping. Several small intermediate plates present in some large meshes, loose or connecting into group of secondary plates subdividing the mesh (Fig. 4c). Papulae in almost every mesh, single (Fig. 4f) or in groups of 2-4. Spines large, stout, with serrated, although slightly blunt distal ends (Fig. 4d), 0.3-0.7 mm in length. Spines grouped in pseudopaxillae, 3-8 spines in each, groups of 6-8 spines occurring rarely (Figs. 4e, 4f). Secondary (intermediate) plates bearing fewer spines than basic plates. Spines in pseudopaxillae ...
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... tubercle. Ends of abactinal plates often overlapping. Several small intermediate plates present in some large meshes, loose or connecting into group of secondary plates subdividing the mesh (Fig. 4c). Papulae in almost every mesh, single (Fig. 4f) or in groups of 2-4. Spines large, stout, with serrated, although slightly blunt distal ends (Fig. 4d), 0.3-0.7 mm in length. Spines grouped in pseudopaxillae, 3-8 spines in each, groups of 6-8 spines occurring rarely (Figs. 4e, 4f). Secondary (intermediate) plates bearing fewer spines than basic plates. Spines in pseudopaxillae arranged in irregular double row. Density of spines arrangement about 11 spines per mm 2 ...
Context 6
... loose or connecting into group of secondary plates subdividing the mesh (Fig. 4c). Papulae in almost every mesh, single (Fig. 4f) or in groups of 2-4. Spines large, stout, with serrated, although slightly blunt distal ends (Fig. 4d), 0.3-0.7 mm in length. Spines grouped in pseudopaxillae, 3-8 spines in each, groups of 6-8 spines occurring rarely (Figs. 4e, 4f). Secondary (intermediate) plates bearing fewer spines than basic plates. Spines in pseudopaxillae arranged in irregular double row. Density of spines arrangement about 11 spines per mm 2 ...
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... side -Skeleton irregular, weakly differentiated (Fig. 4g). Longitudinal arrangement indistinct, except for series of plates adjacent to adambulacral series. Adambulacral spines grouped in double row. Actinolateral plates small, four-lobed, bearing 5-6 spines. Inferomarginal plates elongated, four-lobed, bearing pseudopaxillae with 6-8 spines in single or double row. Inferomarginal plates ...
Citations
... specimens were not identified at the species level. These genera have proven very challenging to identify, and a complete taxonomic and phyologenetic re-evaluation would be necessary [8,19,43,57,58]. Table 1. ...
Abstract
Sea stars are a diverse and important component of the Southern Ocean benthos. However, scarce information is available regarding their diversity, distribution, evolution, and taxonomic uncertainties persist for multiple taxa. The Magellanic Region (south of Chile) remains under-sampled despite its pivotal location for species distribution and diversity, being located at the crossroad of three ocean basins. In this study, we assessed the biodiversity of coastal Magellanic sea stars and their affinities with other oceanic bioregions. An integrative approach combining morphological identification with DNA barcoding was implemented to highlight taxonomic discrepancies such as suspected synonymy and unrecognised diversity. Firstly, we identified a total of 15 species from the coastal Magellanic Region and reported the occurrence of Cycethra frigida Koehler, 1917 for the first time in this region. The distribution of these 15 species ranged from only in South America to circumpolar, bipolar, or possibly cosmopolitan. Secondly, we highlighted possible synonymy in two species pairs within the genera Anasterias and Odontaster. This preliminary biodiversity assessment forms an important baseline for monitoring and conservation purposes, especially in the face of distribution shifts as a response to climate change and the increased presence of invasive species. Developmental mode has previously been suggested to be important in shaping biogeographical patterns. However, developmental mode was insufficient to explain the observed patterns, and other factors (e.g., physiological constraints, competition, bathymetrical range, and the possibility of passively rafting on kelp) are suggested to be at least equally important. Finally, an increase in barcoding effort is needed to better capture phylogeographic patterns for each species, both by increasing the number of specimens investigated and by covering a broader geographical range.
... Our specimen possessed a higher number of abactinal spines (up to 144). However, differences in the number of abactinal spines alone cannot be regarded as a stable character for Henricia species identification [25]. Therefore, we consider that Korean H. djakonovi is the same species as the holotype specimen. ...
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.
