Alexander Semenov, Russland
Info
Polymastia arctica (Merejkowsky, 1878)
Polymastia is a genus of sponges that includes numerous species. These are small to large, crusted or dome-shaped sponges with a smooth surface and many teat-shaped projections (papillae). In areas with strong wave effects, the teat structures in this genus do not grow in a straight shape, as is usual, but in a wavy shape.
The type locality for describing of the Arctic Nipple Sponge Polymastia arctica is the White Sea. The color is yellowish. The surface is free of silt.
Scientists examined the hypothesis of whether Polymastia is a cosmopolitan genus, but found that the individual species each have a limited range.
The redescription of the type material of Polymastia arctica (Merejkowsky, 1878), which was synonymized with Polymastia mamillaris, and comparison with species of Polymastia mamillaris and other common Arctic and northeast Atlantic species showed that Polymastia arctica is a valid species. Polymastia arctica differs from visually similar species Polymastia mamillaris and Polymastia penicillus by the presence of a thick (90–180 μm) collagen layer, the presence of spicules in the inner layers of the papillae, and the formation of buds at the top of the papillae.
Synonymised names
Rinalda arctica Merejkowsky, 1878 · unaccepted (genus transfer)
Polymastia is a genus of sponges that includes numerous species. These are small to large, crusted or dome-shaped sponges with a smooth surface and many teat-shaped projections (papillae). In areas with strong wave effects, the teat structures in this genus do not grow in a straight shape, as is usual, but in a wavy shape.
The type locality for describing of the Arctic Nipple Sponge Polymastia arctica is the White Sea. The color is yellowish. The surface is free of silt.
Scientists examined the hypothesis of whether Polymastia is a cosmopolitan genus, but found that the individual species each have a limited range.
The redescription of the type material of Polymastia arctica (Merejkowsky, 1878), which was synonymized with Polymastia mamillaris, and comparison with species of Polymastia mamillaris and other common Arctic and northeast Atlantic species showed that Polymastia arctica is a valid species. Polymastia arctica differs from visually similar species Polymastia mamillaris and Polymastia penicillus by the presence of a thick (90–180 μm) collagen layer, the presence of spicules in the inner layers of the papillae, and the formation of buds at the top of the papillae.
Synonymised names
Rinalda arctica Merejkowsky, 1878 · unaccepted (genus transfer)
