To refer to this article use this url: http://contributionstozoology.nl/vol85/nr03/a04


Contributions to Zoology, 85 (3) – 2016

Sponge-collecting from a drifting ice floe: the Porifera obtained in the Kara Sea by the Dutch Polar Expedition 1882-83

Rob W. M. van Soest

Naturalis Biodiversity Center, P.O. Box 9517, 2300 RA Leiden, The Netherlands. E-mail: rob.vansoest@naturalis.nl

Keywords: Arctic fauna,carnivorous sponges,new species,Varna expedition.

Abstract


Sponges from the Kara Sea (Arctic Russia) collected by the Dutch Polar Expedition 1882-83 are identified and discussed. The expedition experienced an unfortunate course of events, as the research vessel RV ’Varna’ was ice-bound and eventually got crushed by ice, leaving the crew and the scientists stranded on an ice floe drifting around in the Kara Sea. The scientists still managed to do many observations and made collections of bottom animals lowering collecting gear through a hole in the ice. After being enclosed for more than a year in the ice, the men travelled in small boats and sledges to the mainland of Russia and from there returned home. The zoological collections were brought to Copenhagen by the Danish research vessel RV ‘Dijmphna’, from where the material was picked up by the Dutch scientists. Most animal groups were subsequently discussed in a series of papers published in the Bijdragen tot de Dierkunde volume 14 (1887). The sponges of the Dutch Polar Expedition were in a rather bad condition when they arrived in Amsterdam and possibly for that reason were largely ignored. They nevertheless appear to be interesting and are here presented as a belated contribution to the 1887 issue, including the description of a species new to science, Lycopodina ruijsi sp. nov. The results are discussed in the framework of our present knowledge of the sponge fauna of the Kara Sea. In Appendix ten already known species are briefly described and SEM images of their spicules provided as a contribution to Kara Sea sponge morphology.

Introduction


The present study is a belated report on the sponges of the Kara Sea collected by the Dutch Polar Expedition of 1882-83 (Snellen, 1886; Snellen and Ekama, 1910). This expedition was intended foremost as a meteorological contribution to the 1st International Polar Year. The expedition plan was to travel by ship (the hired Norwegian RV ‘Varna’) to the mouth of the Yenisei River, in Western Siberia, and to spend the winter period observing weather conditions and measuring a large number of meteorological parameters. The opportunity was taken to make also observations of the natural history of the region, which included collecting arctic bottom fauna. The expedition was ill-fated due to the loss of the ship in the Kara Sea, caused by crushing ice masses. By chance, the Danish research vessel ‘Dijmphna’ became ice-bound alongside of the ‘Varna’ and the two vessels and their scientific staff and crews shared almost a year of drifting - lodged firmly in the ice floe - along with the currents of the Kara Sea. The ‘Dijmphna’ remained intact, while the Dutch during and after the demise of the ‘Varna’ were living on the ice in a prefabricated house brought along. In the fall of 1883, the Dutch expedition members travelled to the mainland by sledges and boats, leaving the heavier instruments and collections on board the ‘Dijmphna’. Shortly before the next winter arrived, the ‘Dijmphna’ became freed of the ice and managed to return to Copenhagen.

In spite of these setbacks, many of the original aims of the Dutch Polar Expedition were still achieved, as the crew and the scientists were able to do their observations from the drifting ice. The Dutch natural history collections were picked up from Copenhagen by expedition members and were deposited in the collections of the Zoological Museum of the University of Amsterdam, now part of the Naturalis Biodiversity Center at Leiden. The collector of the expedition team, J.M. Ruijs, published the results of the natural history of the Kara Sea (Ruijs, 1887; see also Snellen and Ekama, 1910: 115-130). He identified and provided numbers of most species and animal groups that were collected, but omitted details on Porifera, other than merely noting the stations, which contained specimens of the group. Monographic reports on the animals collected by the Dutch Polar Expedition were published by Carpenter (1887: comatulids) and Kerbert (1887: Fishes). Other reports used expedition material in more general studies (e.g. Augener, 1933: polychaetes).

This study provides evidence on the identity of the sponge taxa collected by Ruijs. It parallels the study of the Porifera of the Danish Dijmphna expedition (Levinsen, 1887), and since the overlap in species is large, it also provides the opportunity to modernize the taxonomy and descriptions of Levinsen. The collection is relatively rich in ‘carnivorous’ sponges, which occur at unusually shallow depths of 75-150 m. Another deep water species, Stylocordyla borealis, likewise was collected at such relatively shallow depth, inducing the upward adjustment of depth occurrence records of the species. The results induced me to review and update the faunal composition of the sponges of the Kara Sea.

Material and methods


The specimens described here are a small part of the collections made in situ by J.M. Ruijs. A total of 30 specimens survived until today, from an estimated amount of at least 200 specimens obtained at 55 of the 83 stations (Table 1). Whether the loss of specimens was intentional or not is unclear from the reports of the expedition. However, due to the difficulty of transporting the soft, easily damaged material from the drifting ice floe to the Zoological Museum of Amsterdam, it is a small miracle any sponge specimen arrived there. Also for that reason, the surviving specimens are poorly documented: of the 30 specimens only 10 had sufficient information on the label to deduce the exact locality (coordinates, date, depth, bottom conditions, collecting gear), the remaining specimens lacked this label information. They are assumed to have been collected at one of the stations indicated in Ruijs (1887: 15-26) as having one or more sponges in the catch (see Table 1). Depth for those specimens is summarized below as between 75 and 170 m, based on the information in the station list. The position and dates of all stations sampled inside the Kara Sea are depicted in Fig. 1.

FIG2

Table 1. Stations of the Dutch Polar (‘Varna’) Expedition which yielded sponges, as noted by J.M. Ruijs (from Ruijs, 1887). Collecting gear indicated by the French ‘faubertage’ involved the use of so called swabs made of hemp in which spiny or wiry bottom organisms become tangled (see Tendal, 2002). The ‘large dredge’ was rectangular and measured 40 × 70 cm. Bold printed rows indicate stations that were mentioned on one or more of the labels of the 30 specimens that survived from the collecting activities of the Dutch Polar Expedition.

FIG2

Fig. 1. Map showing course and stations of the Dutch Polar (‘Varna’) Expedition 1882-83 in the southwest Kara Sea (from Snellen and Ekama, 1910). Inset map of the Kara Sea and environs, made by Norman Einstein, November 2005, taken from Wikipedia (http://commons.wikimedia.org/wiki/File:Kara_Sea_map.png) under the GNU Free Documentation License.

The collecting methods varied along with the events that occurred during the expedition. Specimens that survived were all obtained by collecting from the ice floe, all from the southern and western parts of the Kara Sea (only a few samples were obtained west of Yugor Strait and the sponges did not survive). The ice conditions were such that even when the ‘Varna’ was still afloat no movements of the ship were possible. This meant that holes or squares had to be sawn in the thinner parts of the surrounding ice in order to be able to lower the collecting gear into the water. The gear consisted to begin with of larger and smaller rectangular and semi-circular dredges, drifting nets and collecting swabs (‘faubertage’) (see Tendal, 2002). During most of the winter period, when the overwintering accommodation had been erected (Fig. 2), all collected material had to be quickly brought inside as the catch became frozen solid more or less immediately after it was brought up. After several ice crushes, which caused loss of dredge nets, the only remaining gear was the large 40 × 70 cm rectangular dredge (Fig. 2 left), and a number of swabs. Most of the material was collected using these two types of gear.

FIG2

Fig. 2. The prefabricated house in which the participants of the Dutch Polar Expedition 1882-83 spent most of their overwintering period on the ice floe drifting around in the Kara Sea. Photo taken by H. Ekama on 13 July 1883 (from Snellen, 1887).

Dredging from drifting ice needed its own improvised methodology. Where normal dredging from a ship means a bottom time of 10-30 minutes, the rate of movement of the ice was so slow, that for the dredge or the swabs to be effective periods of more than 20 hours were no exception. At times, drift was minimal and the dredge so heavy that it ploughed deeply into the soft bottom, with the result that it arrived at the surface filled with ‘grey loam’ that had to be sieved patiently (and inside the living quarters!).

Material was sorted at the locality on the ice, preserved in 60-70% ethanol, and stored in tins, glass tubes and glass bottles, the latter probably a.o. containing the sponges. Delivered in Amsterdam, the sponges remained unidentified, until the Norwegian spongologist E. Arnesen (1867-1928) arrived for a four months’ work visit to what later became the Zoological Museum of the University of Amsterdam (ZMA) in 1903 by invitation of the director Professor Max Weber. She provisionally identified most specimens, except for ZMA Por. 01012 and 02382, which according to the label were identified by O. Schmidt (1823-1886). However, this cannot be concluded with certainty, because his characteristic handwriting is not on the labels, and Schmidt’s biography (Desqueyroux-Faúndez and Stone, 1992) makes no mention of any visit to Amsterdam, so briefly before his death in 1886. It is perhaps surprising that the Dutch contemporary spongologist G.C.J. Vosmaer (1854-1916), author of two publications on the sponges of the Barents Sea (adjacent to the Kara Sea) (Vosmaer, 1882, 1885), was apparently not involved in the identification of the Varna sponges, but this is understandable because at that time he was working in Naples (1882-1889).

All specimens are registered in the ZMA collection, now housed in Leiden, and labelled ‘Kara Zee Varna-Exp. 1882/83’, with E. Arnesen’s unpublished names. The specimens were re-identified by the present author and provided with additional new labels bearing the names mentioned below. To make the descriptions and illustrations, below and in the Appendix, thick sections, dissociated spicule slides and SEM preparations were made in the way described in Van Soest et al., (2014). Measurements of spicules are based on 15 spicules of each distinguished type, randomly chosen.

Results


Sponges collected by the Dutch Polar Expedition 1882-83

The following 11 species were identified in the Varna collection:

LIST: TYPE 5

One new species was detected in the material, which is described below. The other species are treated in the Appendix. Since most of the species were already described by Levinsen (1887) on the basis of the Dijmphna material that was collected in the same area in the same period, I provide summarized descriptions and measurements in the Appendix, including SEM images of the spicules of all the collected species of the Dutch Polar Expedition as a contribution to the morphological information on Kara Sea sponges.

Systematic description of a species new to science

Class Demospongiae

Order Poecilosclerida

Family Cladorhizidae

Genus Lycopodina Lundbeck, 1905

Lycopodina ruijsi sp. nov. (Figs 3a-g)

FIG2

Fig. 3. Lycopodina ruijsi sp. nov., holotype ZMA Por. 01012, a habitus (scale bar 1 cm); b-g SEM images of spicules; b longest style, b1 details of apices of longest style; c shorter style, c1 details of apices of shorter style; d microstyle; e large anisochela; f small anisochela; g forceps.

Holotype. ZMA Por. 01012, Russia, Kara Sea, Varna Expedition, locality not noted on the available labels, depth between 75 and 170 m, coll. J.M. Ruijs, 1882-1883; label text: ‘Esperia spec. Varna-Exp. 1882/83, O. Schmidt det.’.

Additional material (not type material). ZMA Por. 15404, Russia, Kara Sea, Varna Expedition, locality not noted on the available labels, depth between 75 and 170 m, coll. J.M. Ruijs, 1882-1883; label text: ‘Clador­hiza spec.’, but there is no further text and no identifier mentioned.

Description. The specimens, dark brown in alcohol, consist of a narrow fleshy stalk-like lower part and a broader blade-like upper part. The holotype (Fig. 3a) is 50 mm long, with the stalk 38 × 5 mm and the main body 12 × 8 mm. The second sample is now broken into three tiny fragments of undetermined shape.

Skeleton. The thinner lower part has a skeleton of loosely packed aligned spicules, the main body has a largely confused skeleton of intercrossing spicule tracts.

Spicules. (Figs 3b-g) Styles, microstyles/strongyles, anisochelae and forcipes.

Styles in a large size range, with overlapping larger (Figs 3b, b1) and smaller (Figs 3c, c1) styles, but not divisible in size categories, overall range 390-875 × 9-11 µm.

Microstyles (Fig. 3d) or microstrongyles, usually with one end with a slight tyle, curved more or less strongly, 63-145 × 2.5­7 µm.

Anisochelae, shaped like the usual Lycopodina chelae, with the shaft uncovered by the upper alae for a shorter or larger stretch, usually the naked shaft is less than 20% of the length of the alae, in two clear non-overlapping size categories, larger (Fig. 3e) with lengths 23-29 µm (average 26.4) and smaller (Fig. 3f) with lengths 11-21 µm (average 15.9).

Forcipes (Fig. 3g), common, with straight legs that are only slightly expanding, with swollen tips, legs 24-45 µm.

Etymology. Named after J.M. Ruijs in recognition of his tireless efforts to collect bottom fauna from a drifting ice floe under extreme polar conditions.

Remarks. The new species belongs to the newly revived genus Lycopodina Lundbeck, 1905 because of its possession of forceps microscleres in combination with the spiculation and architecture of the genus Asbestopluma. Hestetun et al. (2015) established on morphological and molecular evidence that Lundbeck’s subgenus Asbestopluma (Lycopodina) deserves recognition at the genus level.

The two specimens differ somewhat in sizes of the spicules, with the holotype having generally slightly longer styles, forcipes, and both categories of anisochelae. The microstyles of ZMA Por. 15404 are more often strongyles and are frequently much more strongly curved than those of the holotype. The anisochelae of 15404 have a longer stretch of shaft visible (resembling those of L. infundibulum), than those of the holotype. For the time being, this is interpreted as variability, but in view of the scanty material and the observed differences I refrain from assigning paratype status to ZMA Por. 15404. Future studies might demonstrate that the two specimens belong to closely related but different species.

The spicule complement is generally similar to that of Lycopodina robusta (Levinsen, 1887) (described below in Appendix), but that species has a different habitus with ‘grooved’ side-branches, and there are no microstyles and only a single category of anisochelae. The latter have their shafts covered entirely by the lateral alae in L. robusta, in contrast with those of the present species.

Two related cladorhizid species occurring in the Arctic region possess two sizes of anisochelae, viz. Asbestopluma (A.) pennatula (Schmidt, 1875) [(with junior synonym Asbestopluma bihamatifera (Carter, 1876) (originally as Esperia cupressiformis var. biha­matifera, see also description in Lundbeck, 1905, p. 51)] and Asbestopluma (A.) furcata Lundbeck, 1905 (p. 54). Both differ clearly from the new species in having sigmancistras, and the larger category of anisochelae in the two species is twice as large (respectively 48-63 µm and 44-54 µm) as that of the present species. The habitus of A. (A.) pennatula is pennate, that of A. (A.) furcata is dichotomously arborescent, unlike the new species.

For further information on Kara Sea cladorhizids collected by the Dutch Polar Expediton 1882-1883 see Appendix.

Comparison with previous studies on sponges of the Kara Sea

The Dijmphna sponges of the Kara Sea, collected at the same time and in the same area by Th. Holm (cf. Bergh et al. 1887), were studied by Levinsen (1887). The results of his study are presented in Table 2, left hand column, with currently accepted names given in the right hand column (from the World Porifera Database (WPD), cf. Van Soest et al., 2015). Also in the latter, asterisks indicate whether the species was also collected by the Dutch Polar Expedition. The collection consisted of specimens of 20 sponge species, several of which were collected outside the Kara Sea (deduced from the shallow depth they were collected). Next to collections made by the ‘Dijmphna’ from the drifting ice floe, there were also some shallow-water sponges collected along the way travelling to and leaving from the Kara Sea. Unfortunately, Levinsen (1887) provided only depth data, so the validity of their Kara Sea occurrence is somewhat in doubt because the precise localities are not given. As could be expected, there is a great resemblance in the sponges collected by the Dutch and Danish expeditions, with 9 out of 11 species of the Dutch collection also represented in the Danish collection. The two species not reported by Levinsen, Tetilla sandalina and Lycopodina ruijsi sp. nov. might easily be hiding in the Danish collection under the 13 reported specimens of Tetilla polyura and among the Esperella cupressiformis ‘varieties’ (respectively 27 and 20 specimens of both varieties).

FIG2

Table 2. Porifera obtained by the ‘Dijmphna’ Expedition to the Kara Sea, collected by Th. Holm, reported and described by G.M.R. Levinsen (1887) (left hand column) with the names corrected on the basis of the present study, and the World Porifera Database (Van Soest et al., 2015, consulted on May 30, 2015) (right hand column). The order of the names follows the treatment in Levinsen’s study. Names with an asterisk were also identified in the present collection.

Further reports on sponges from the Kara Sea are those of Fristedt (1887, 4 species), Hentschel (1929, 3 species), Rezvoi (1924, 12 species), Rezvoi (1931, 6 species), and especially Koltun (1959, 1966, 49 species). The latter author also partially included the results of the previous authors. Lundbeck (1905) renamed Esperella picea sensu Levinsen as Iophon frigidus, and this name is so far retained in the WPD awaiting reexamination. It is assumed here that Iophon frigidus is a junior synonym of Iophon piceum. The reported Kara Sea sponge fauna is here assembled in Table: in the left part the currently accepted names, which number 60 species and in the right part the original combinations and synonyms found in the original studies.

FIG2

Table 3. Sponges reported from the Kara Sea. The first four columns provide the identities of 60 species under the currently accepted systematics with as references either the World Porifera Database (Van Soest et al., 2015, consulted on May 30, 2015) or the present study. The next three columns provide one or more original genus and species names for the Kara Sea species and their original references.

Almost all of the records of sponges were obtained from more eastern and northern parts of the Kara Sea, which are deeper and/or from inshore localities or from the mouth of the Yenisei. The sponges of the southwestern Kara Sea, where the Dutch Polar Expedition and the ‘Dijmphna’ collected their specimens, are known almost exclusively from these 19th century research activities.

Conclusion


On the basis of the present and previous published sources, the sponge fauna of the Kara Sea is found to contain 60 species: 5 of these belong to the Calcarea, 55 are Demospongiae, with as the most striking feature a proportionally high amount of ‘carnivorous’ sponges of the genus Lycopodina. So far no records exist of Hexactinellida, although the eastern deeper parts are likely to contain such sponges. The sponges of the southeastern parts of the Kara Sea are known predominantly from the ice floe collections of the Dutch and Danish expeditions of 1882-83.

Acknowledgements


Dr O.S. Tendal (Zoologisk Museum of Copenhagen) helped to answer the question whether the present collection of sponges is indeed all that remains from the Dutch Polar (‘Varna’) Expedition of 1882-83. Olga Bozhenova (ZIN RAS, St. Petersburg) provided copies of Rezvoi (1924, 1931). Elly Beglinger (Naturalis) helped locating and registering the Varna specimens.

Received: 7 June 2015

Revised and accepted: 30 June 2015

Published online: 30 August 2016

Editor: L.P. van Ofwegen

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Appendix


Additional taxonomic descriptions of sponges collected by the Dutch Polar Expedition 1882-83

Class Demospongiae

Order Tetractinellida

Suborder Astrophorina

Family Theneidae

Thenea valdiviae Lendenfeld, 1907 (Fig. 4a-g)

FIG2

Fig. 4. Thenea valdiviae Lendenfeld, 1907, ZMA Por. 02382, a habitus of specimen and fragment (scale bar 1 cm); b-g SEM images of spicules; b oxea, b1 detail of apices of oxea; c anatriaene, c1 detail of cladome of anatriaene; d protriaene, d1 detail of cladome of protriaene; e cladome of dichotriaene; f amphiaster/spiraster; g differently shaped plesiasters.

Material. ZMA Por. 02382, Russia, Kara Sea, Varna Expedition, locality not noted on the available labels, depth between 75 and 170 m, coll. J.M. Ruijs, 1882-1883. Label text: ‘Thenea muricata Gray (Vosmaer) det. O. Schmidt’.

Description. Lump-shaped specimen (Fig. 4a) with at least two oscules, apparently without sieve plates, and a small fragment; dark brown color, hispid surface.

Skeleton. Radiately confused, with long spicules protruding beyond the surface.

Spicules. (Fig. 4b-g) Oxeas, anatriaenes, protriaenes, dichotriaenes, amphiasters/spirasters, plesiasters.

Oxeas (Figs 4b, b1), curved, flexuous, often broken in the preparations, in a large size variation, frequently around 3500 × 15-20 µm in size, but largest observed oxea 6500 × 36 µm.

Anatriaenes (Fig. 4c, c1), with rhabds 2000-7500 × 16-42 µm, cladomes relatively narrow, 66-240 µm, cladi 58-300 × 9-22 µm.

Protriaenes (Figs 4d, d1) (not common), with flaring cladi, with rhabds up to 3000 × 30 µm, cladome up to 400 µm, cladi 300-400 × 20-25 µm.

Dichotriaenes (Fig. 4e), length of rhabds variable, up to 7200 × 76 µm, with cladomes 720-960 µm in diameter, primary cladi shorter than secondary, primary 200-240 × 30-60 µm, secondary 250-780 × 20-54 µm.

Spirasters/amphiasters (Fig. 4f), variable in size, ray number and shaft thickness, but not clearly separated in two categories, ray number 8-11 (average 9.2), size 21-31 µm (average 24.9).

Plesiasters (Fig. 4g), finely spined, with 3-5 rays, 52-111 µm.

Remarks. This specimen is assigned to Thenea valdiviae on the basis of Steenstrup and Tendal’s (1982) and Cárdenas and Rapp’s (2015) observations on the North Atlantic and Arctic Thenea species. The present specimen is not in a very good condition, so the sieve plates, which are characteristic for T. valdiviae, may not have been preserved. The rarity of the protriaenes and the plesiasters is in accordance with descriptions of T. valdiviae.

Suborder Spirophorina

Family Tetillidae

Tetilla polyura Schmidt, 1870 (Fig. 5a-g)

Tetilla polyura Schmidt, 1870: 66, pl. 6 fig. 8

FIG2

Fig. 5. Tetilla polyura Schmidt, 1870, ZMA Por. 02362, a habitus of fragment (scale bar 1 cm); b-g SEM images of spicules; b oxea, b1 details of oxea; c anatriaene, c1 detail of cladome of anatriaene; d ‘normal’ protriaene; e cladomes of ‘2+1’ protriaenes; f sigmaspire; g dragma of raphides/oxeotes, g1 detail of dragma..

Material. ZMA Por. 02362, Russia, Kara Sea, Varna Expedition, locality not noted on the available labels, depth between 75 and 170 m, coll. J.M. Ruijs, 1882-1883. Label text: ‘Bruchstück wahrscheinlich Tetilla polyura O. Schm., KKY‘ + illegible small label, possibly original.

Description. A dark brown, conical-shaped fragment (Fig. 5a), spinous, firm condition.

Skeleton. Radiate.

Spicules. (Fig. 5b-g) Oxeas, anatriaenes, protriaenes,, sigmaspires, raphides.

Oxeas (Fig. 5b, b1) in two rather sharply divided categories, (1) long, thin and flexuous with gradually tapering thin apices, usually broken in the slides, largest unbroken oxea up to 4200 × 7 µm, (2) short, fusiform, 600-1080 × 12-19 µm.

Anatriaenes (Fig. 5c, c1), common, with long wispy shaft, usually broken, up to 2100 × 8 µm. Cladomes narrow, 29-63 µm in diameter, cladi 28-81 × 4-8 µm.

Protriaenes, shafts thin and wispy, 960-1600 × 3-10 µm, in two types, (1) normal shaped cladomes (Fig. 5d), and (2) with ‘2+1’ cladomes (Fig. 5e), long cladus 88-225 × 3-7 µm, short cladi 24-78 × 3-5 µm.

Sigmaspires (Fig. 5f), C or S-shaped, faintly centrotylote, 10-13 µm.

Raphides/oxeotes (Fig. 5g, g1), sinuous or wispy, in trichodragmas or frequently single, length 215-345 µm, thickness around 1 µm.

Remarks. The fragment conforms to Schmidt’s description and figure as far as the spicules are concerned (both anatriaenes and protriaenes present). The outer morphology deviates in lacking the conical surface elevations, but that can be attributed to the fragmentary condition of the specimen. There is considerable similarity in the spiculation with Tetilla sandalina Sollas, 1886 (see below), but that species lacks anatriaenes.

Tetilla sandalina Sollas, 1886 (Fig. 6a-f)

FIG2

Fig. 6. Tetilla sandalina Sollas, 1886, ZMA Por. 02353, a habitus of four fragments presumed to be from a single specimen (scale bar 1 cm); b-f SEM images of spicules; b long thin oxea, b1 details of apices of long thin oxea; c short fusiform oxea, c1, details of apices of short oxea; d ‘2+1’ protrianee, d1 details of cladome and pointed end of a ‘2+1’ protriaene; e sigmaspires; f raphide.

Material. ZMA Por. 02353, Russia, Kara Sea, Varna Expedition, locality not noted on the available labels, depth between 75 and 170 m, coll. J.M. Ruijs, 1882-1883. Label text: ‘Tetilla cranium (Müller)’ no further text, no identifier.

Description. The sample consists of five fragmentary specimens (Fig. 6a) which may be part of a single larger specimen. One fragment is attached to a shell. Color grey-brown, surface very spinous-hairy, condition firm.

Skeleton. Radiate, predominantly made up of the shorter oxeas.

Spicules. (Fig. 6b-f) Oxeas, protriaenes, raphide-like oxeas, sigmaspires.

Oxeas in two overlapping categories, (1) long, with gradually tapering thin apices (Fig. 6b, b1), usually broken in the slides, largest unbroken oxea up to 3900 × 36 µm, (2) short, fusiform (Fig. 6c, c1), 600-1260 × 12-21 µm.

Protriaenes (Fig. 6d, d1), with ‘2+1’ cladomes, shaft thin and wispy, 1260-2900 × 2-6 µm; long cladus 22-147 × 1.5-4 µm, short cladi 15-51 × 1-3 µm.

Sigmaspires (Fig. 6e), C or S shaped, distinctly centrotylote, 10-16 µm.

Raphides/oxeotes (Fig. 6), sinuous or wispy, in trichodragmas or frequently single, length 320-400 µm, thickness around 1 µm.

Remarks. Cárdenas and Rapp (2015) described a specimen of this species from the adjacent Barents Sea and their spicule size data are closely similar to the above cited with the exception of the sigmaspires, which were 15-25 µm. A major discrepancy with previous records, including those of Cárdenas and Rapp (2015) is the depth, at which the present fragment was collected. The precise depth is unfortunately not known, but the dredgings of the Dutch Polar Expedition did not exceed 200 m in depth. Most of the dredgings were done between 70 and 125 m (Ruijs, 1887). The species shares with T. polyura (see above) the ‘2+1’ protriaenes, but differs in the absence of anatriaenes.

Order Polymastiida

Family Polymastiidae

Radiella hemisphaerica (Sars, 1872) (Fig. 7a-d)

FIG2

Fig. 7. Radiella hemisphaerica (Sars, 1872), ZMA Por. 01844, a habitus (scale bar 1 cm); b-d SEM images of spicules; b longest tylostyle, b1 details of apices and middle of longest tylostyle; c intermediate subtylostyle, c1 details of apices and middle of intermediate subtylostyle; d ectosomal tylostyle.

Trichostemma hemisphaericum Sars, 1872: 63, pl. 6 figs 1-15.

Polymastia hemisphaerica; Vosmaer, 1885: 12, pl. 1 figs 20-21, pl. 2 figs 17-20, pl. 3 figs 1-5, pl. 5 figs 8-11, 16; Koltun, 1966: 78, text-fig. 51, pl. 29 figs 1-5.

Material. ZMA Por. 01844, Russia, Kara Sea, Varna Expedition, stat. 70, 71.3333°N 63.6333°E, depth 77.5 m, coll. J.M. Ruijs, field nr. 40, 20 February 1883; label text ‘Polymastia mammillaris Müller, det. E. Arnesen’; ZMA Por. 01850, Kara Sea, Varna Expedition, locality not noted on the available labels, depth between 75 and 170 m, coll. J.M. Ruijs, 1882-1883; label text ‘Bruchstück Polymastia spec.’ + illegible small label, possibly original.

Description. Discoidal, circularly-flattened, dark brown sponges (Fig. 7a), with a transparent fringe at the peripheral edge, at the upper surface covered by light brown papillae, with a single central larger oscular papilla. Ten individuals (ZMA Por. 01844) and a small fragment on a mussel (01850). Largest individual 5 cm in diameter, 1 cm in thickness, papillae number approximately 100; smallest complete individual 1 cm in diameter, with four papillae including the oscular papilla. Fringe of the larger specimens approximately 3-4 mm wide.

Skeleton. The upper surface skeleton consists of a palisade of smaller spicules, which are proper tylostyles, arranged at right angles to the surface; choanosomal skeleton consists of a subectosomal confused layer of intermediate sized spicules, and below that and also forming the lower surface are the longest spicules parallel with the undersurface and fanning out into the fringe. All these longer spicules are ‘subtylostyles’, i.e. they are stylote with a faint subterminal constriction.

Spicules. (Fig. 7b-d) Fusiform tylostyles and subtylostyles.

Longest subtylostyles (Fig. 6b, b1), possibly divisible in the choanosomal ones 1146-2100 × 16-19 µm and those forming the fringes, 2400-3600+ × 15-26 µm (upper size probably considerably longer but no unbroken spicules were observed in the preparations).

Intermediate subtylostyles (Fig. 7c, c1) 468-1520 × 11-13 µm.

Ectosomal tylostyles (Fig. 7d) 162-306 × 8-18 µm.

Remarks. The specimens conform closely to Sars’ (1872) description and figures, and at least to Vosmaer’s (1885) and Koltun’s (1966) P. hemisphaerica. Other records may need further verification.

Order Suberitida

Family Stylocordylidae

Stylocordyla borealis (Loven, 1868) (Fig. 8a-c)

FIG2

Fig. 8. Stylocordyla borealis (Loven, 1868), ZMA Por. 02224, a habitus (scale bar 1 cm); b centrotylote oxea; c ectosomal oxea, c1 blunt apex of ectosomal oxea (images copied from Van Soest, 2002: Fig. 1D-G).

Hyalonema boreale Loven, 1868: 105, pl. 2

Hyalonema longissima Sars, 1872: 73, pl. 6 figs 35-45 (new synonymy)

Stylocordyla borealis; Van Soest, 2002: 225, fig. 1 (with synonymy and distributional data); Uriz et al., 2010: 245 (lectotype description and further discussion)

Material. ZMA Por. 02224, Russia, Kara Sea, Varna Expedition, locality not noted on the available labels, depth between 75 and 170 m, coll. J.M. Ruijs, 1882-1883. Label text: ‘Stylocordyla, det. E. Arnesen’. The specimen has already been treated and illustrated in the Systema Porifera (see Van Soest, 2002: 225-226).

Description. Club-shaped sponge (Fig. 8a) on a thin stalk, with a root system of spicule bundles, anchoring the specimen in the soft bottom. Length of specimen 9 cm, stalk approximately 0.5 cm in diameter, main body 2 cm long 1.2 cm in diameter, bearing a single oscule of 2 mm diameter.

Skeleton. The stalk skeleton consists of aligned long oxeote spicules. The stalk penetrates somewhat into the main body where shorter oxeotes fan out towards the surface. Smaller oxeotes form bundles inbetween the long oxeotes and at the surface small oxeas form a palisade.

Spicules. (Fig. 8b-c) Oxeotes in several size classes.

Long oxeotes (Fig. 8b) from the stalk, occasionally centrotylote, up to 3000 × 50 µm.

Intermediate oxeotes from the main body, usually centrotylote, 400-1150 × 4-10 µm.

Small oxeotes from the main body, 300-450 × 4 µm.

Ectosomal microxeas (Fig. 8c, c1), often with bluntly rounded ends, up to 100 × 2 µm.

Remarks. Previous treatments of this species so far have ignored Hyalonema longissimum Sars, 1872, collected slightly to the north of the type locality of S. borealis, as an almost certain synonym of this species. The differences are entirely size and growth form, whereas all other details are similar to those of S. borealis.

Order Poecilosclerida

Family Hymedesmiidae

Phorbas claviger (Levinsen, 1887) (Fig. 9a-e)

FIG2

Fig. 9. Phorbas claviger (Levinsen, 1887), a habitus of ZMA Por. 00834, a1 habitus of ZMA Por. 00842 (scale bar 1 cm); b-e SEM images of spicules of ZMA Por. 00834; b large acanthostyle, b1 details of apices of large acanthostyle; c small acanthostyle; d oxeote tornote, d1 details of apices of tornote; e arcuate isochela.

Esperella (Myxilla) clavigera Levinsen, 1887: 360, pl. 31 figs 3-6.

Ectyomyxilla (?) clavigera; Hentschel, 1929: 948.

Not: Hymedesmia clavigera; Alander, 1942: 34.

Material. ZMA Por. 00834, Russia, Kara Sea, Varna Expedition, locality not noted on the available labels, depth between 75 and 170 m, coll. J.M. Ruijs, 1882-1883; label text: ‘Dendoryx spec. ?, det. E. Arnesen, Varna Expeditie LL3’; ZMA Por. 00842, Russia, Kara Sea, Varna Expedition, locality not noted on the available labels, depth between 75 and 170 m, coll. J.M. Ruijs, 1882-1883; label text: ‘Desmacidon spec. Kara Zee, Varna-Exped. 1882/83’, no further text, no identifier.

Description. The specimens (Fig. 9a, a1) at first glance appear to be branch-shaped, but closer inspection reveals them to be thinly encrusting worm tubes. One of the specimens (00842, Fig. 8a1) has a light brown surface with pale oval patches, which are likely to be remnants of areolated pore fields. Size of specimens up to 2 cm long, tube diameter including the encrusting sponges 4-5 mm. Sponge thickness 1-1.5 mm.

Skeleton. From surface to substratum the skeleton shows three layers, (1) a densely spiculated tangential ectosomal crust, (2) a choanosomal skeleton consisting of thick spicule tracts carrying the surface skeleton, in between there are numerous, loose spicules, mostly microscleres, and (3) a continuous hymedesmioid basal skeleton of single acanthostyles with heads embedded in the substratum (worm tube surface).

Spicules. (Fig. 9b-e) Acanthostyles, tornotes, isochelae.

Acanthostyles in two categories, (1) long with heavily spined swollen head (Fig. 9b, b1), and spines gradually diminishing towards the points, 292-1032 × 18-22 µm (heads 24-33 µm), (2) small, entirely heavily spined (Fig. 9c), with swollen heads, 131-271 × 10-14 µm (heads 18-20 µm).

Tornotes (Fig. 9d, d1), fusiform oxeotes, approximately symmetrical, with mucronate apices, often slightly curved, 348-522 × 8.5-12 µm.

Isochelae (Fig. 9e), arcuate, robust, usually with smoothly and continuously curved shaft and ends, and short vaguely mucronate alae, 29-39 µm.

Remarks. The data match those of Levinsen’s description, although most of the present spicule sizes have a higher upper limit. The species is here assigned to Phorbas Gray, 1867 (which means that according to the ICZN the species name has to undergo a mandatory change to claviger) on account of the presence of thick spicule tracts carrying the surface skeleton combined with the presence of a hymedesmioid basal skeleton of single acanthostyles. The genus assignment of Hentschel (1929) as Ectyodoryx was mistaken, as this (sub)genus has a reticulate skeleton and lacks the hymedesmioid basal skeleton.

Alander (1942) reported a species as Hymedesmia clavigera from the Skagerrak at greater depth (540 m), but he did not provide a description. Moreover, it appears that he mistook Levinsen’s species for Hymedesmia clavigera Lundbeck, 1910, because in his key he states that the chelae are 40-50 µm and that the species would also occur at Stavanger. This latter record is apparently based on Burton’s (1930) record of Hymedesmia clavigera Lundbeck, not Levinsen.

So far this species appears to be endemic to the Kara Sea.

Family Cladorhizidae

Lycopodina lycopodium (Levinsen, 1887) (Fig. 10a-f)

FIG2

Fig. 10. Lycopodina lycopodium (Levinsen, 1887), a habitus of ZMA Por. 01002, a1 habitus of ZMA Por. 15309 (scale bar 1 cm); b-f SEM images of spicules of ZMA Por. 01002; b longest style, b1 details of apices and middle of longest style; c shorter style, c1 details of apices and middle of shorter style; d microstyle; e anisochela; f forceps.

Esperella cupressiformis var. lycopodium Levinsen, 1887: 365, pl. 29 s 12-13, pl. 31 s 15, 16d.

Asbestopluma (Lycopodina) lycopodium; Lundbeck, 1905: 62, pl. 2 s 15-17, pl. 11 s 6-7.

Lycopodina lycopodium; Hestetun et al., 2015: 335.

Material. ZMA Por. 01002, Russia, Kara Sea, Varna Expedition stat. 68, 71.3°N 63.5167°E, depth 135 m, coll. J.M. Ruijs, field nr. 83, 18 June 1883; label text:’Esperella cupressiformis var. lycopodium Lev., Varna-Exp. E. Arnesen det’; ZMA Por. 15309, Russia, Kara Sea, Varna Expedition, stat. 70, 71.3333°N 63.6333°E, depth 77.5 m, coll. J.M. Ruijs, field nr. 40, 20 February 1883, label text: ‘Asbestopluma spec.’, not original, no identifier mentioned; illegible small label present, possibly original.

Description. Two stalked-pennatulifom specimens (Fig. 10a, a1), the largest of which is 6 cm high, with a naked stalk of 1.5 cm and the part with side branches ca. 4.5 cm. Side branches 2-3 mm. The second specimen is 3.5 cm high. Color in alcohol red-brown or pale beige. Both specimens have become broken.

Skeleton. Axial skeleton of aligned longer styles, with side tracts of smaller styles at right angles to the axial skeleton. Surface skeleton crowded with clusters of anisochelae.

Spicules. (Fig. 10b-f) Styles, microstyles, anisochelae, forcipes.

Styles in two size categories, both slightly fusiform, (1) longest (Fig. 10b, b1) 1110-1170 × 11-12.5 µm, (2) shorter (Fig. 10c, c1), 570-780 × 10-13 µm.

Microstyles (Fig. 10d), slightly curved, equidiametrical until close to the pointed apex, rather variable in length and thickness, 115-180 × 2-8 µm.

Anisochelae (Fig. 10e) with the characteristic Asbestopluma-shape with lower alae sharply incised and provided with one or more spines on the middle ala rim, upper side alae covering the shaft entirely, 11.5-14.5 µm.

Forcipes (Fig. 10f), not common, with thin, somewhat irregular legs, ending in faintly swollen apices, sometimes crossed in the lower parts, length 28-48 µm.

Remarks. This species is the type of the newly revived genus Lycopodina Lundbeck, 1905. The shape of the specimens and the size of spicules are identical to the drawings and measurements given by Levinsen (1887). Lundbeck’s (1905) drawings of the habit of his specimens in his pl. II figs. 15 and 16 also conform to the present material, but the drawing of pl. II fig. 17 appears different. Lundbeck’s measurements of the forcipes (50-56 µm) exceed those of the present and Levinsen’s measurements, whereas measurements from a specimen from Rockall Bank, W of Ireland (Van Soest and Baker, 2011: table 2, as Asbestopluma) are smaller than the present. L. lycopodium still remains a species that needs revision before it can be assumed that the wide distribution (Kara Sea, The Faroes) is accurate.

Lycopodina robusta (Levinsen, 1887) (Fig. 11a-e)

FIG2

Fig. 11. Lycopodina robusta (Levinsen, 1887), a habitus of ZMA Por. 01003a, a1 habitus of ZMA Por. 01003b (scale bar 1 cm); b-e SEM images of spicules of ZMA Por. 01003a; b longer style, b1 details of apices and middle of longer style; c shorter style, c1 details of apices and middle of shorter style; d anisochela; e forceps.

Esperella cupressiformis var. robusta Levinsen, 1887: 364, pl. 29 figs 10-11, pl. 31 figs 7-9, 10a-c, 11-14.

Asbestopluma (Lycopodina) cupressiformis; Lundbeck, 1905: 58, pl. 2 figs 11-14, pl. 11 figs 4-5.

Material. ZMA Por. 01003a, Russia, Kara Sea, Varna Expedition, stat. 70, 71.3333°N 63.6333°E, depth 77.5 m, coll. J.M. Ruijs, field nr. 40, 20 February 1883, label text: ‘Esperella cupressiformis var. robusta’; ZMA Por. 01003b, Russia, Kara Sea, Varna Expedition stat. 56, 71.4167°N 64.2667°E, depth 92 m, coll. J.M. Ruijs, field nr. 70, 15 May 1883; label text: ‘Esperella cupressiformis var. robusta’.

Both specimens are in the same bottle, 01003a in a glass tube.

Description. Two stalked specimens (Fig. 11a, a1), red-brown in color, with a distinct separation in a thin stalk and a thick somewhat club shaped body, but keeping the elongate pennatuliform form. Side branches in the main body are directed upwards causing a ‘grooved’ outlook of it. Size of the larger more complete specimen, which is fixed on a worm tube, 30 mm in total. with stalk 12 × 1-1.5 mm, and main body 18 × 2.5 mm. The second specimen is less than half the size of the first specimen.

Skeleton. Consisting of a tight-packed axial tract of spicules and branching tracts of the upper body. The surface of the main body is crowded with anisochelae.

Spicules. (Fig. 11b-e) Styles, anisochelae and forcipes.

Styles (larger, Fig. 11b, b1), (smaller, Fig. 11c, c1) variable in size, but not clearly divisible in categories, 550-910 × 10-13 µm.

Microstyles not certainly present, only one or two small styles were observed.

Anisochelae (Fig. 11d), as usual in Lycopodina, with upper side alae covering the shaft entirely and spiked rim of lower alae, 20-27 µm.

Forceps (Fig. 10e), fairly common, with short, straight, relatively thick legs curving outwards, ending in clearly developed swollen tips, 31-40 µm.

Remarks. The specimens conform closely to Levinsen’s Esperella cupressiformis var. robusta in shape as well as spicule complement. Lundbeck (1905) assigned this species to the synonymy of Asbestopluma (Lycopodina) cupressiformis (Carter, 1874), because of the similarity in spicule sizes and shapes with Carter’s descriptions. Lundbeck’s specimens as depicted in his pl. II figs 11-14 appear to be different from Carter’s drawings (1874: pl. 14 figs 16-19). Possibly, some of Lundbeck’s specimens, e.g. those reported from The Faroes, are genuine L. cupressiformis, but others, e.g. those from East Greenland may possibly be a different species. Spicule sizes of Lundbeck and the present ones are more or less the same as those of Carter’s specimens, but the differences in habitus point toward specific difference.

Lycopodina infundibulum (Levinsen, 1887) (Fig. 12a-g)

FIG2

Fig. 12. Lycopodina infundibulum (Levinsen, 1887), ZMA Por. 01004, a habitus (scale bar 1 cm); b-g SEM images of spicules; b longest style, b1 detail of head of longest style; c intermediate-sized style, c1 details of apices of intermediate-sized style; d short style, d1 details of apices of short style; e wispy thin style; f anisochelae; g light-microscopic image of rare forceps.

Esperella infundibulum Levinsen, 1887: 366, p. 29 fig. 14, pl. 31 figs 17-19.

Asbestopluma (Lycopodina) infundibulum; Lundbeck, 1905: pl. 2 figs 20-21, pl. 11 fig. 9.

Lycopodina infundibulum; Hestetun et al., 2015: 335.

Material. ZMA Por. 01004, Russia, Kara Sea, Varna Expedition, locality not noted on the available labels, depth between 75 and 170 m, coll. J.M. Ruijs, 1882-1883; label text: ’Esperella infundibuliformis Lev. n.var., E. Arnesen det.’.

Description. A single specimen (Fig. 12a), light brown in alcohol, consisting of an open cup-shaped main body with a thin curved stalk ending in a small holdfast. Total length of specimen 27 mm, stalk 20 × < 1 mm, size of cup 9 × 5 mm.

Skeleton. Stalk consists of aligned tightly packed styles, main body a confused mass of styles with anisochelae crowded over the surface.

Spicules. (Fig. 12b-g) Styles, anisochelae, forcipes.

Styles in a large size range, but not clearly separable in categories, overall size 155-1340 × 5.5-20 µm, but with some overlappings three categories may be distinguished, (1) the larger styles (Fig. 12b, b1) are usually >1000 × 15-20 µm, (2) intermediate sizes, usually 300-600 × 5-10 µm, normal shaped (Fig. 12c, c1), or with thin wispy ends (Fig. 12e), the latter from the cup walls, and (3) short styles (Fig. 12d, d1), 155-420 × 2-5 µm, apparently from the rim of the cup (cf. Lundbeck, 1905: 69).

Anisochelae (Fig. 12f), with upper side alae only partially covering the shaft, which is naked for approximately 1/3 of its length, lower alae with spiked rims, 16-23 µm.

Forceps (Fig. 12g), not common (not found on the SEM stub, only on the glass slide), size 65-70 µm.

Remarks. The label text, which was made by the original identifier, the Norwegian spongologist E. Arnesen, concluded that this specimen belongs to an undescribed variety of Asbestopluma (Lycopodina) infundibulum. However, Lundbeck’s (1905) extensive treatment of specimens from the The Faroes as well as specimens from the Kara Sea from Levinsen’s collection, shows that there is no difference between his descriptions and the present specimen.

Family Esperiopsidae (?)

Semisuberites cribrosa (Miklucho-Maclay, 1870) (Fig. 13a-c)

FIG2

Fig. 13. Semisuberites cribrosa (Miklucho-Maclay, 1870), ZMA Por. 02004a, a habitus (scale bar 1 cm); b-c SEM images of spicules; b long style, b1 details of apices of long style; c short style, c1 details of apices of short style.

Veluspa polymorpha var. cribrosa Miklucho-Maclay, 1870: 6, pl. 1 figs 12-16.

Semisuberites artica Carter, 1877: 39.

Cribrochalina sluiteri Vosmaer, 1882: 36, pls 1 and 3; Levinsen, 1887: 352, pl. 29 figs 6-9, pl. 30 fig. 6.

Tragosia sluiteri; Rezvoi, 1924: 246.

Semisuberites cribrosa; Van Soest and Hajdu, 2002: 661 (with further synonyms and discussions).

Material. ZMA Por. 2400a, Russia, Kara Sea, Varna Expedition, locality not noted on the available labels, depth between 75 and 170 m, coll. J.M. Ruijs, 1882-1883; label text: ‘Tragosia sluiteri (Vosm.), 20’, no identifier; ZMA Por. 2400b, Russia, Kara Sea, Varna Exped. stat. 20, 71.1333°N 64.45°E, depth 92 m, coll. J.M. Ruijs, 20 February 1883, label text: ‘Tragosia sluiteri (Vosm.), det. E. Arnesen’; ZMA Por. 02400c, Russia, Kara Sea, Varna Exped. stat. 20, 71.1333°N 64.45°E, depth 92 m, coll. J.M. Ruijs, 20 February 1883, label text: ‘Tragosia sluiteri (Vosm.), det. E. Arnesen’; ZMA Por. 02004d, Russia, Kara Sea, Varna Exped. stat. 3, 70.25°N 60.4167°E, depth 77.5 m, coll. J.M. Ruijs, 1 September 1882, label text: ‘Tragosia sluiteri (Vosm.), det. E. Arnesen’; ZMA Por. 2400e, Russia, Kara Sea, Varna Exped. stat. 20, 71.1333°N 64.45°E, depth 92 m, coll. J.M. Ruijs, 20 February 1883, label text: ‘Tragosia sluiteri (Vosm.), det. E. Arnesen’; ZMA Por. 02004f, Russia, Kara Sea, Varna Exped. stat. 70, 71.3333°N 63.6333°E, depth 77.5 m, coll. J.M. Ruijs, 20 February 1883, label text: ‘Tragosia sluiteri (Vosm.), det. E. Arnesen’; ZMA Por. 15282, Russia, Kara Sea, Varna Expedition, locality not noted on the available labels, depth between 75 and 170 m, coll. J.M. Ruijs, 1882-1883; label text: ‘Hymeniacidon spec.’, no further text, no identifier.

Description. Numerous specimens of brown-colored (alcohol preserved) stalked tubular sponge (Fig. 13a) with a wide, occasionally flaring or with outwardly curved vent (‘trumpet-shaped’). Largest available specimen 18 cm high, stalked part approximately 10 × 0.4/0.5 cm grading into the tubular body of 7-8 × 1.5 cm, vent approximately 1 cm in diameter. Surface irregular, without macroscopic openings. Consistency soft, limp.

Skeleton. Loosely reticulated with vaguely delimited spicule tracts rising upwards in the wall of the tubes giving rise to frequent perpendicular or oblique side tracts, equally vaguely delimited, ending in loose bouquets at the surface. The smaller spicules are concentrated in the surface bouquets, the larger spicules make up the choanosomal tracts.

Spicules. Styles only.

Styles (Fig. 13b-c), smooth, faintly fusiform, in two overlapping size categories, (1) (Fig. 13b, b1) 500-565 × 9-11 µm, (2) (Fig. 13c, c1) 215-260 × 5-7 µm.

Remarks. The specimens match those of the revised description in Van Soest and Hajdu (2002), but swollen heads are absent in the specimens studied here. The affiliation of Semisuberites should be investigated anew, as the lack of chelae, the size categories of the styles and the structure of the skeleton renders membership of the order Poecilosclerida and family Esperiopsidae less likely. These are indications that the genus should be referred to the order Suberitida, along with the genus Ulosa, which is a likely Suberitida, according to molecular sequence data presented by Redmond et al., 2013.

Additional ‘Varna’ material. Two additional Dutch Polar Expedition samples are present in the Naturalis sponge collection, ZMA Por. 15316 labelled ‘Hymenia­cidon spec.’, no identifier mentioned, which appears to be an indeterminable piece of an Asbestopluma or Lycopodina stalk, the other ZMA Por. 01077 labelled ‘Ficulina sp., E. Arnesen det.’, which turned out to be an encrusting colonial tunicate, possibly Didemnum sp.