Bulletin Zoologisch Museum 0JN1VERS1TE1T VAN AMSTERDAM Vol. 8 No. 12 1982 Calcareous sponges of the Netherlands (Porifera, Calcarea) Th. van Koolwijk Abstract in field The taxonomy of calcareous sponges occurring the Netherlands is reviewed, using observations of live individuals, microscopical examination of individual skeletons and study of the breeding cycle. This led to the conclusion that a new species had to be erected and other in found be: Leucosole-species reidentified. The common calcareous sponges the Netherlands are to nia variabilis (Haeckel, 1872), Scypha ciliata (Fabricius, 1780) and Scypha scaldiensis n.sp. INTRODUCTION and that a wide intraspecific variability exists in shape and size and in the presence or A recent of the Nether- absence of One de- publication on sponges spicule categories. cannot lands (Van Soest, 1977) provides data on calca- scribe species only by looking at spicule varia- also reous sponges based on the taxonomy of Burton' s tion; morphological, histological, cytolo- monograph (1963)- Unfortunately, it has been gical, ecological and life history characters shown that Burton has too far have to be used. gone by lumping large numbers of species (e.g. Hartmann, 1964; Van Soest (1977) mentioned the following cal- Jones, 1964; Tuzet, 1965; Borojevic, 1967). careous sponges: Leucosolenia botryoides (El- These authors do not share Burton's belief, lis & Solander, 1786); Clathrina coriacea (Mon- that spicules provide the only valid characters tagu, l8l8); Scypha ciliata (Fabricius, 1780); 90 Fig. 1. Spicules of Leucosolenia variabilis; a, T-shaped triradiate; b, T-shaped quadriradiate; Small Small c, Triradiates; d, Quadriradiates; e, Large oxea; f, réfringent oxea; g, non refringent oxea. Grantia In compressa (Fabricius, 1780). view were studied, using light microscope (including of the it reexamine his above, was necessary to interference contrast and polarized light) and and to these in data study sponges the field. scanning electron microscope. Three different preparation techniques were used. Thin hand made sections, mounted in artificial canada bal- AND METHODS to Mere MATERIAL sam, study skeletal features. spicule slides were gained after solution of the soft Calcareous studied in the field tissue of the in sodium sponges were sponge hypochlorate. and The in the laboratory on variation in morpholo- résidu was washed in water and mounted in and the artifificial canada balsam. In order be able gy spiculation, breeding periods (in to genus Scypha), growth, population density and to study the microstructure of spicules, dried of the ecology. pieces sponge were covered with a thin made material SEM. These observations were in different layer of gold, to study the with localities coast of two of along the the Netherlands, Every weeks a number specimens were during a period of 30 months, from July 1978 to stained in Hemalun-eosin, after decalcifying December 1980. Five of these localities, all with 10% acetic acid. After staining, oocytes the along coast of the Eastern Scheldt (SW part and embryos, if présent, were visible. of the Netherlands), were chosen as permanent stations, to be visited every two weeks: Flauwersbocht (artificial rocky shore); Wemel- TAXONOMY dinge (pontoon); Schelphoek (industrial har- bour); Kats (marina); Sas van Goes (sluice). Genus Leucosolenia Bowerbank, 1861 at Sampling was done directly from the shore (Order Homocoelida, Family Leucosoleniidae) low tide, sometimes using a scraping net, or by snorkling; occasionally scuba dive techniques were used for sublittoral sampling. Spicules Leucosolenia variabilis Haeckel, 1870 (fig. 1) 91 Synonyms.- (pers.comm. Van Soest). Elsewhere the species Ascandra 1897: complicata; Maitland, 55. is common along the coasts of Western Europe. Ascartes fabricii; Maitland, 1897-' 55. Distribution outside Europe (Burton, 1963): Leucosolenia botryoides; Rousseau, 1902: 11; Arctic, Mediterranean, South Africa, Straits of Van Soest, 1977: 264, pi- 1 A-B. Magellan, Chile. Leucosolenia fabricii; Rousseau, 1902: 12. Leucosolenia complicata; Rousseau, 1902: 12. Ecology.- variabilis L. occurs in a variety of environ- Description.- ments and shows no specific preference for sub- Sponge asconoid, appearing in two transitio- stratum, although it is commonly found attached nal forms, either forming a rather compact to algae, hydroids, etc. out bushy mass (bushy fonn) or spreading over the substratum form). Sponge connect- Discussion (spreading .- ed with the has basally substratum, by little, ana- The taxonomy of the Homocoelidae been a often bearing diverticu- stomosing, basal tubes, problem for a long time, mainly because of the la. Oscular tubes are long, smooth and slightly mistakes made by Bowerbank (1864, 1866, 1874) curved, they show no tendency to anastomose or and Haeckel (1872). Minchin (1904) revised the form diverticula. Surface minutely hispid, genus Leucosolenia (Ascandra) thoroughly and colour alive and in vents terminal; spirit: Sara (1953» 1956b) completed the taxonomy and Skeleton consists of of white, yellow or grey. ecology the genus. triradiates, quadriradiates and oxea. L. complicata appears in a bushy and in an Triradiates, slender, sagittal, unpaired arborescent form (the latter form is never than angle distinctly larger 120°, unpaired ray found in L. variabilis). Its habitats are rock- 80-120 and 50-100 ym by 7 nm, paired rays pm by pools of the sublittoral it is very rarely 7 Mm. T-shaped triradiates are relatively found in situations in which it is liable to be 30-60 by 5-10 pair- left at low tide. The is scarce, unpaired ray \m Mm, dry sponge very ed 50-70 by 5-10 rays torn pm. fragile. The very long oscular tubes are always Quadriradiates, similar to triradiates, api- provided with diverticula. The oscular rim is cal into ray 10-40 Mm by 7 Mm, projecting long. The unpaired angle of the triradiates is cloacal the cavity. only slightly thicker than the paired angles, Oxea, curved at the proximal end, lance- but always longer than the paired rays. Small headed, 80-320 Mm by 2-9 Mm; short, slender, not non-réfringent oxea are present (Minchin, réfringent, straight 70-110 Mm by 2-4 Mm; do. 1904; Sara, 1953, 1956b). L. non-réfringent. is considered of fabricii a synonym L. complicata. Distribution.- botroides L. is a very characteristic The potential distribution of sponges in the (Ellis & species Solander, 1786), it appears Netherlands is restricted to few areas only only in one form and in one situation. The with suitable substratum. L. variabilis is very species is always found growing over algae, common in the Oosterschelde (Eastern Scheldt). oscular forming a dense cluster of smooth The is difficult to find in the species more tubes, rising from a basal reticulum of fine Westerschelde and to be tubes. appears relatively The sponge resembles a bunch of bananas. the islands Texel and in scarce on Terschelling The oscular rim is short. The spiculation of L. the northern part of the Netherlands. Occasio- botryoides resembles the spiculation of L. vari- the has been found attached nally species to abilis, however all spicules in L. botryoides cork and seaweed on the beaches the west along are much more robust, T-shaped triradiates are coast. The species was found recently in the abundant and large proximally thickened oxea sublittoral of the closed the Greve- sea arm are present (Michin, 1904; Sarâ, 1953, 1956a, lingen (also in the SW part of the Netherlands) 1956b). 92 2. of Tubar Subendosomal Fig. Spicules Scypha ciliata; a, triradiate; b, Oxea; c, triradiates; d, Endosomal quadriradiates. Genus Clathrina Gray, 1867 This species has been found washed ashore on (Order Homocoelida, Family Clathrinidae) the beach of Camperduin (Van Soest, 1977); it is apparently an allochthonous species. The ma- Clathrina coriacea (Montagu, l8l8) terial conforms to the description of this species in Burton (X963)• This species has been found only once in the The family Grantiidae is distinguished from coastal waters of the Netherlands (Van Soest, the family Sycettidae by the following charac- 1977: 264, pl. 1 C). It is apparently an autoch- ters: Transition between the syconoid and the thonous species. The material conforms to the leuconoid form, appearing sacciform, compress- description of this species in Burton (1963). ed; vents apical or dispersed; dermal cortex The family Clathrinidae is distinghuished present, consisting of tangential radiates and from the family Leucosoleniidae by the follow- oxea. characters: ing Always a clathrate mass of ana- stomosing tubes, vents never markedly tubular; Genus only regular triradiate systems are present; Saypha Gray, 1821 the larva is parenchymula larva, instead of the (Order Helerocoelida, Family Sycettidae) Amphiblastula larva found in the Leucosolenii- dae. Scypha ciliata (Fabricius, 1780) (fig. 2) Synonyms.- Genus Grantia Fleming, 1828 Sycandra ciliata; Vosmaer, 1882: 51. (Order Heterocoelida, Family Grantiidae) Sycandra ciliata, trans.var. coronata; Vos- 1882: maer, 51. Grantia compressa (Fabricius, 1780) Sycon ciliatum; Maitland, 1897: 55; Van 93 1977; 265 (in pi. 2 A other of the Netherlands the Soest, part), . whereas in parts length apparently does not exceed 5 cm. Description.- Sponge syconoid, tubular, erect, cylindri- cal. Surface papillate and hispid. Distal cham- Discussion.- bers grouped around central atrial cavity. Vent Dubosq & Tuzet (1937, 1941) considered S. apical usually without fringe, sometimes with ciliata and S. coronata as being two separate Texture and fringe. soft to