Suberites spermatozoon ( Schmidt, 1875 )

Pereira, Raquel, Larsson, Mats, Cárdenas, Paco & Thollesson, Mikael, 2025, Swedish marine demosponge fauna (Porifera: Demospongiae) sampled 80 years after Jägerskiöld’s inventory, European Journal of Taxonomy 983, pp. 1-64 : 52

Suberites spermatozoon ( Schmidt, 1875)

Cometella spermatozoon Schmidt, 1875: 116 pl. I fig. 2.

Suberites spermatozoon – Fristedt 1885: 18–19; 1887: 429–430.

? Ficulina spermatozoon – Burton 1930: 496.

Choanites spermatozoon – Alander 1942: 79.

Material examined (5 specimens)

SWEDEN • 1 spec.; Gullmaren , Skåreskär; 58.2973° N, 11.5150° E; 105–100 m depth; 24 May 2014; Erica Mejlon leg. [Skåreskär 140424]; dredge; P062-140504-1; GenBank no.: OM436260 (coxI); voucher: GNM Porifera 1154 • 1 spec.; same collection data as for preceding; P062-140504-2; voucher: GNM Porifera 1155 • 1 spec.; same collection data as for preceding; P062-140504-3; GenBank nos: OM436257 (coxI), OM415618 (28S D3-D5); voucher: GNM Porifera 1156 • 1 spec.; same collection data as for preceding; P062-140504-4; voucher: GNM Porifera 1157 • 1 spec.; Gullmaren , Skåreskär; 58.2942° N, 11.5138° E; 105–100 m depth; 5 May 2014; Erica Mejlon leg. [Skåreskär, 140505]; dredge; P062-140513-1; voucher: GNM Porifera 1158 .

Description

The specimens are small, only a couple of centimeters long, pyriform with a hollow body and a long peduncle. The same pedicle can be connected to several bodies. Our specimens were not attached to hard substrate when dredged in the muddy bottoms. A simple osculum is present on the top of each specimen. Colour yellowish-grey, both alive and preserved in ethanol.

Skeleton

The skeleton was composed by (sub)tylostyles, either straight or flexuous, with a bimodal size distribution, i.e., there is too much overlap to be two bona fide size classes, measuring: a) 320– 430.3 - 840 ± 78.1 ×2.5 - 6.6 - 10 ± 1.8 µm (N=80), and b)–135 - 247.7 - 317.5± 38.7 ×2.5 - 5.3 -10 ± 1.6 (N =54). These megascleres sometimes present abnormal forms, such as styles or strongyles. Microscleres are microspined centrotyloted slightly curved strongyles or oxeas. The tyle is less evident than in other Suberites species and could present a displacement from the centre of the spicule. These microscleres measure 11.3– 32.5 –72± 10.3 ×2– 2.6 – 4 +/ 0.5 (N=130). Finally, all specimens have modified microrhabds that are spherical and smooth. These spheres are found in the peduncles of the specimens but in very low numbers making them difficult to find in spicules preparations. The diameter is the same as for the length of the microscleres.

Ecology and distribution

The type locality of Suberites spermatozoon is near Mandal (southern Norway), but it has been reported in the Kara Sea ( Fristedt 1887), Bering Sea ( Hentschel 1929) and Sweden ( Fristedt 1885; Alander 1942). In Sweden, this species was common in Gullmaren fjord, between 65 and 90 m depth ( Alander, 1942), which is where we collected our specimens.

Remarks

The distribution of this species is poorly known, as its small size and fragile bodies combined with its habitat (muddy bottoms) makes it difficult to detect. Furthermore, it has been reported from great depths varying from 38 m ( Fristedt 1887) to 400 m depth ( Alander 1935), which makes sampling and observation nearly impossible by any other means than dredging. The specimens here examined come from Gullmaren fjord, ca 100 m depth.