Contributions to Zoology, 85 (3) – 2016Rob W. M. van Soest: Sponge-collecting from a drifting ice floe: the Porifera obtained in the Kara Sea by the Dutch Polar Expedition 1882-83

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Appendix

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

Class Demospongiae

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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.