962 research outputs found
Saccocamera Grischenko & Gordon & Melnik 2018, n. gen.
No full textSaccocamera n. gen. Type species. Saccocamera ampulla n. sp. Etymology. Latin saccus, sac, and camera, chamber, alluding to the discrete sac-like form of the incubation chamber. Gender feminine. Diagnosis. Colony squat, wart-like, with peristomes radiating around 1–2 calyciform areas occupied by alveoli. Peristomial rims typically with projections. Colony surface mostly granular. Gonozooid discrete, sac-like, narrowing to laterally facing ooeciostome, lacking surficial ribbing, alveoli or pores. Remarks. Saccocamera n. gen. is established here for a small suite of deep-sea species that resemble Disporella Gray, 1848, but differ in having simple lageniform, sac-like incubation chambers that do not ramify between autozooids, and which lack pores and structural features on their surface like ribbing and alveoli. Apart from the type species, newly described here from the CCZ, other species include Saccocamera minima (Moyano, 1991) n. comb. from 1200–1800 m off northern Chile, Saccocamera minicamera (Gordon & Taylor, 2010) n. comb. from 750–1181 m on the Chatham Rise, New Zealand, and Saccocamera minutissima (Gordon & Taylor, 2010) n. comb. from 943–1097 m on the Chatham Rise. Moyano (1991) had suggested that his new species Disporella minima might be accommodated within a new genus, but left the question open. Gordon & Taylor (2010) considered this possibility but reasoned that the small size and saccular nature of the gonozooid might be no more than a consequence of small colony size, i.e. large colonies have large incubation chambers, small colonies have small chambers. Additionally, the occurrence of the gonozooid on the surface of the colony instead of being embedded in it might also be associated with small colony size and limited growth—large species have the capacity for increase in colony thickness, such that frontal growth of kenozooidal chambers can be achieved relatively quickly, partially or wholly concealing gonozooid surfaces. However, the finding of yet another small, squat deep-sea species with a simple saccular incubation chamber that lacks pores (unlike Disporella), or any surficial reticulation or chambers, strengthens the case for segregation of these species from Disporella. Unfortunately, the ancestrula is not known in any species of Saccocamera n. gen., but it is assumed to be adnate. Moyano (1991) further believed that, if his new species were to be assigned to a new genus, then Disporella cookae David & Pouyet, 1986 would be congeneric. In fact, this species has a pedunculate colony form and large gonozooid very like that found in Alyonushka n. gen., Calyssopora n. gen. and Rallocamera n. gen., but differs from these in having smooth calcification and a different form of incubation chamber in relation to alveoli; its ooeciopore is virtually flush with the gonozooid surface. It either belongs to yet another new genus or might be accommodated in a stretched concept of Calyssopora. In having smooth calcification it is reminiscent of Dartevellopora neozelanica, but in that species the column is made up of peristomial tubes with occluded apertures.Published as part of Grischenko, Andrei V., Gordon, Dennis P. & Melnik, Viacheslav P., 2018, Bryozoa (Cyclostomata and Ctenostomata) from polymetallic nodules in the Russian exploration area, Clarion - Clipperton Fracture Zone, eastern Pacific Ocean-taxon novelty and implications of mining, pp. 1-91 in Zootaxa 4484 (1) on page 33, DOI: 10.11646/zootaxa.4484.1.1, http://zenodo.org/record/143784
Alyonushka hystricosa Grischenko & Gordon & Melnik 2018, n. sp.
No full textAlyonushka hystricosa n. sp. (Figs 2L, 24, 25) Material examined. Holotype: ZIRAS 1/50711, colony attached to particle of nodule, YMG R.V. Gelendzhik cruise GLD4–09, Stn 199, 7 January 2011, 13.09042° N, 133.55185° W, 4758 m. One specimen only. Etymology. Latin, hystricosus, prickly, thorny, alluding to the minutely prickled colony surface. Description. Sole colony erect, pedunculate and subcalyciform, with outwardly flaring capitulum of relatively short autozooidal peristomes (Fig. 24), up to 10 in single irregular whorl. Column narrowest below middle, widening to slightly bulbous base thickened by development of layers of overlapping flattened alveoli/kenozooidlike chambers (Fig. 25D). Entire external skeletal surface of colony densely covered by minutely branched tiny prickles except for distal half of peristomes. Surface of autozooidal peristomes irregularly granular-tubercular, tubercles tending to be slightly elongated and in partly linear series down sides of peristome (Fig. 25C). Aperture subcircular to suboval, rim thin, generally facing obliquely outwards. Interior of peristomes smooth or lightly textured, lacking spinulation (Fig. 25B, C, F). Gonozooid occupying calyx center (Fig. 24A–C), large, slightly convex, its surface prickled, centrally imperforate, surrounded by irregular alveoli around periphery (Fig. 24A). Ooeciostome (Figs 24A–C, 25A, B, E), very short, subcircular, with thin prickled rim, inner surface with low irregularities (Fig. 25A). Ooeciopore smaller than autozooidal apertures. Ancestrula and very early colony stages not seen. Measurements (mm). Holotype, ZIRAS 1/50711 (Figs 24, 25): Colony height 2.08; capitulum 1.31 × 1.08; base diameter at substratum 0.69; minimum column diameter 0.43; ZL 0.403–0.618 (0.513 ± 0.068) (n = 9); PeL 0.213–0.303 (0.264 ± 0.026) (n = 9); PeD 0.128–0.153 (0.143 ± 0.010) (n = 9); ApL 0.154–0.175 (0.165 ± 0.008) (n = 9); ApW 0.106–0.128 (0.118 ± 0.007) (n = 9); OpD 0.087 (n = 1). Remarks. Alyonushka hystricosa n. sp. is most readily distinguished from the type species and Alyonushka echinata n. sp. (below) by the smooth, non-spinulose inner surface of zooidal peristomes, as well as the surface appearance of the gonozooid. Distribution. Recorded from a single station with coordinates 13.09042° N, 133.55185° W, at 4758 m depth.Published as part of Grischenko, Andrei V., Gordon, Dennis P. & Melnik, Viacheslav P., 2018, Bryozoa (Cyclostomata and Ctenostomata) from polymetallic nodules in the Russian exploration area, Clarion - Clipperton Fracture Zone, eastern Pacific Ocean-taxon novelty and implications of mining, pp. 1-91 in Zootaxa 4484 (1) on page 40, DOI: 10.11646/zootaxa.4484.1.1, http://zenodo.org/record/143784
Calyssopora clarionensis Grischenko & Gordon & Melnik 2018, n. sp.
No full textCalyssopora clarionensis n. sp. (Figs 33–35) Material examined. Holotype: ZIRAS 1/50719, colony attached to nodule particle, YMG R.V. Gelendzhik cruise GLD4–11, Stn 220, 30 April 2012, 12.88593° N, 133.18168° W, 4916 m. Paratype 1: ZIRAS 2/50720, colony attached to nodule particle, YMG R.V. Yuzhmorgeologiya cruise YMG4–13, Stn 291, 27 July 2014, 13.00083° N, 132.49723° W, 4865 m. Paratype 2: ZIRAS 3/50721, colony attached to nodule particle, YMG R.V. Gelendzhik cruise GLD4–09, Stn 186, 1 January 2011, 13.45140° N, 133.53807° W, 4872 m. Paratype 3: ZIRAS 4/50722, detached colony, YMG R.V. Gelendzhik cruise GLD4–12, Stn 246, 3 April 2013, 13.00578° N, 132.95280° W, 4935 m. Additional material: YMG18–01, Stn 24; YMG4–07, Stn 134; GLD4–08, Stns 144, 150; GLD4–11, Stn 209; YMG4–13, Stns 287, 290; YMG4–14, Stns 327, 339. Total specimens examined 13. Etymology. Pertaining to the Clarion Fracture, which defines the northern margin of the potential mining area. Description. Colony erect, compact (Fig. 33) relative to other species, with apron-like base, vasiform; column topped by capitulum comprising peripheral autozooidal peristomes surrounding central concavity. Skeletal surface irregularly textured with minute dimples and granules except for base of column. Pores tiny, simple, sparse. Autozooids in well-developed infertile colonies in single whorl of 6–7 (Fig. 35I –P), with incipient zooid bud developing frontally at lower level between each pair; apertures bilaterally symmetrical, with raised, granular, arcuate lateral rims and concave frontal and abfrontal rims (Figs 33A, 34A–F, M), hence somewhat mitriform in profile. Wall interiors densely covered by prickle-like granules (Fig. 34N, P). Alveoli rare between peristome bases abfrontally. Autozooids in mature brooding colonies with c. 8 peristomes in primary whorl and c. 7 slightly smaller peristomes at lower level (Fig. 34A). Gonozooid single, developing from female zooid in central concavity of capitulum, ventricose in vicinity of ooeciostome only, occupying part or all of concavity, ooeciostome strongly curved and hood-like (Figs 33A, 34A, B, G, H, J), its surface granular-tubercular, ooeciopore concealed from frontal view. Sparse, relatively large alveoli adjacent to gonozooid within concavity (Fig. 34A, C). Ancestrular zooid erect, not seen in isolation; earliest growth stage encountered comprising three very similar zooids (Fig. 35A–D) such that it is not clear which is ancestrular; protoecium not obvious. Elongation and outward curving of peristomes resulting in small vasiform colony (Fig. 35F–H) with budding of additional zooids lateroabfrontally between peristomes (Fig. 35M, N). Measurements (mm). Holotype, ZIRAS 1/50719 (Fig. 33A): Colony height 1.94; capitulum 1.28 × 1.22; base at substratum 0.75 × 0.83; column diameter 0.47–0.76; ZL 0.653–0.882 (0.784 ± 0.088) (n = 8); PeL 0.221–0.303 (0.255 ± 0.026) (n = 8); PeD 0.203–0.233 (0.218 ± 0.011) (n = 8); ApL 0.196–0.228 (0.211 ± 0.011) (n = 8); ApW 0.155–0.192 (0.168 ± 0.013) (n = 8). Gonozooid (n = 1): GZL 0.483; GLW 0.491; OsL 0.348; OsW 0.226; OsH 0.207. Paratype 2, ZIRAS 3/50721 (Fig. 33C): OpL 0.091 (n = 1); OpW 0.108 (n = 1). Paratype 3, ZIRAS 4/50722 (Fig. 33D): OpL 0.098 (n = 1); OpW 0.124 (n = 1). Remarks. Calyssopora clarionensis n. sp. differs most obviously from the type species in having a gonozooid with a curved ooeciostome and prickled zooidal interiors. Distribution. Recorded from 13 stations within coordinates 12.84500– 14.33668° N, 129.07338– 134.46597° W, at depth range 4690–5222 m.Published as part of Grischenko, Andrei V., Gordon, Dennis P. & Melnik, Viacheslav P., 2018, Bryozoa (Cyclostomata and Ctenostomata) from polymetallic nodules in the Russian exploration area, Clarion - Clipperton Fracture Zone, eastern Pacific Ocean-taxon novelty and implications of mining, pp. 1-91 in Zootaxa 4484 (1) on pages 51-55, DOI: 10.11646/zootaxa.4484.1.1, http://zenodo.org/record/143784
Abyssoecia elevata Grischenko & Gordon & Melnik 2018, n. sp.
No full textAbyssoecia elevata n. sp. (Figs 2G, H, 13–15) Material examined. Holotype: ZIRAS 1/50703, colony detached from nodule, YMG R.V. Yuzhmorgeologiya cruise YMG4–13, Stn 302, 30 July 2014, 13.16460° N, 132.52885° W, 4934 m. Paratype 1: ZIRAS 2/50704, colony detached from nodule, YMG R.V. Yuzhmorgeologiya cruise YMG4–06, Stn 106, 2 September 2006, 13.26750° N, 134.51797° W, 4805 m. Paratype 2: ZIRAS 3/50705, colony attached to particle of nodule, YMG R.V. Gelendzhik cruise GLD4–09, Stn 191, 3 January 2011, 13.40957° N, 133.47513° W, 4897 m. Paratype 3: ZIRAS 4/50706, colony fragment (with gonozooid) detached from nodule, YMG R.V. Yuzhmorgeologiya cruise YMG4–13, Stn 282, 12 July 2014, 13.41580° N, 132.28818° W, 4946 m. Additional material: YMG4–04, Stn 44; YMG4–06, Stn 99; YMG4–07, Stns 129, 135; GLD4–09, Stn 196; YMG4–13, Stn 313. Total specimens examined 11. Etymology. Latin, elevatus, raised, alluding to the elevation of colony above the substratum. Description. Colony suberect to erect, flabellate (Fig. 13), pale lemon yellow (Fig. 2G, H), supported by founding zooids and additional pillars derived from autozooids (Figs 13B, F, 15C–I); up to 5.77 mm long and 9.09 mm wide. Arcuate lateral margins of large colonies tending to curve proximad, occasionally meeting around a space or spaces, creating open calyciform shape (Figs 2G, 13A). Supportive pillars of about 4–8 connate zooids, each budded in such a way as to be bent, with proximal portion subvertical, descending towards substratum (e.g. Fig. 15F), and frontodistal part forming peristomial tubes (e.g. Fig. 15I). No kenozooids. Surface calcification of colony forming sinuous concentric striae (Figs 13D, 14A, E–J) and having fibrous (planar-spherulitic) microstructure (Fig. 14K); pseudopores small, simple, sparse, evenly distributed. Frontal surface with evenly distributed autozooidal peristomes, all obliquely inclined in direction of colony growth, generally longer towards colony margin, fully formed apertures mostly circular (Fig.14J), calcified terminal diaphragms rare. New zooids budded from part of distobasal wall of preceding zooid (Fig. 14G, H), hence zooids partly overlapping. Interior wall surface of imbricated foliated fabric of wedge-shaped crystallites; no spinules (Fig. 14K). Gonozooid simple, transversely reniform (Fig. 14A), wedged in among autozooidal peristomes at colony margin, moderately densely pseudoporous, narrow ooeciostome directed outwards, with more or less circular ooeciopore (Fig. 14B–E). Ancestrula (Figs 14L–N, 15D–I, K), suberect, inclined at 50–60° angle to substratum. Protoecium typically flared at base, narrowing at base of peristome but no distinction in surface calcification of needle-like crystallites; peristome tending to be angled to one side (Figs 14L, 15H, I). Later daughter zooids tending to form descending outgrowths to substratum, helping to support ancestrula as colony grows; no basal kenozooids. Measurements (mm). Holotype, ZIRAS 1/50703 (Fig. 13A–B): Colony length 3.28, width 4.88, height 2.79; ZL 0.597–0.802 (0.711 ± 0.074); PeL 0.062–0.191 (0.108 ± 0.037); PeD 0.148–0.185 (0.171 ± 0.012); ApL 0.136–0.165 (0.149 ± 0.008); ApW 0.124–0.143 (0.133 ± 0.006). Paratype 3, ZIRAS 4/50706 (Fig. 14A–E): Gonozooid (n = 1): GZL 0.703; GZW 0.880; GZH 0.383; OsL 0.155; OsD 0.133; OpD 0.111. Non-type specimen YMG4–04, Stn 44 (Figs 14L–M, 15G–K): Ancestrula (n = 1): AnH 0.903; AnPeD 0.221; AnPrL 0.247; AnPrW 0.234. Remarks. Eleven colonies, representing a range of sizes, were isolated from the nodule samples; only one was fertile. The elevated, flabellate form of the colony is consistent, with the pillar-like supports providing stability as the colony expands. Distribution. Recorded from 10 stations within coordinates 13.09421– 13.49873° N, 130.80695– 134.72239° W, at depth range 4787–5050 m.Published as part of Grischenko, Andrei V., Gordon, Dennis P. & Melnik, Viacheslav P., 2018, Bryozoa (Cyclostomata and Ctenostomata) from polymetallic nodules in the Russian exploration area, Clarion - Clipperton Fracture Zone, eastern Pacific Ocean-taxon novelty and implications of mining, pp. 1-91 in Zootaxa 4484 (1) on pages 25-29, DOI: 10.11646/zootaxa.4484.1.1, http://zenodo.org/record/143784
Alyonushka echinata Grischenko & Gordon & Melnik 2018, n. sp.
No full textAlyonushka echinata n. sp. (Figs 26, 27) Material examined. Holotype: ZIRAS 1/50712, colony attached to nodule particle, YMG R.V. Yuzhmorgeologiya cruise YMG4–13, Stn 288, 26 July 2014, 12.94712° N, 132.54418° W, 5056 m. Paratype: ZIRAS 2/50713, colony attached to particle of nodule, YMG R.V. Gelendzhik cruise GLD4–11, Stn 206, 18 April 2012, 13.47733° N, 133.02290° W, 4824 m. Total specimens examined two. Etymology. Latin, echinatus, spiny, prickly, alluding to the minutely prickled colony surface. Description. Colony erect, pedunculate and subcalyciform, with outwardly flaring capitulum of seven short autozooidal peristomes (Fig. 26), in single whorl. Column of more or less equal diameter to base or broadening somewhat at base, thickened, with small, shallow alveolar chambers at surface (Fig. 26A). Entire external skeletal surface of colony covered by tiny minutely branching prickles (Fig. 27K), except for distal part of peristomial surface where prickles are a little less complex (Fig. 27H). Pores simple, most evident on outer surface of peristomial tubes (Fig. 26C, F). Surface of autozooidal peristomes with crystallites aligned into coarse, upwardly directed micro-nodules (Fig. 27E); skeletal ultrastructure of generally narrow, irregular imbricated crystallites. Aperture subrounded, rim granulated or prickled, inner surface of peristomes also with simple and minutely branching prickles/spinules (Fig. 27I, J). Gonozooid (Figs 26A–F, 27A–D) occupying calyx center, large, slightly convex, with sparsely distributed tiny openings of alveoli, centrally imperforate, surrounded by irregular alveoli around periphery. Ooeciostome(s) difficult to discriminate from larger alveoli; one broken, one more evident (Fig. 27B, F, G), very short with thin prickled rim, inner surface with sparse low irregularities. Ooeciopore much smaller than autozooidal apertures. Ancestrula and very small colonies not seen. Measurements (mm). Holotype, ZIRAS 1/50712 (Fig 26A–C): Colony height 1.54; capitulum 1.02 × 0.66; base at substratum 0.41 × 0.51; ZL 0.331–0.478 (0.386 ± 0.049) (n = 7); PeL 0.144–0.303 (0.204 ± 0.059) (n = 7); PeD 0.153–0.178 (0.163 ± 0.009) (n = 7); ApL 0.121–0.153 (0.135 ± 0.013) (n = 7); ApW 0.098–0.133 (0.114 ± 0.014) (n = 7); OpD 0.044 (n = 1). Remarks. Alyonushka echinata n. sp. is most readily distinguished from the type species by its short peristomes with a less-barbed lineated surface texture, and the form of the gonozooid and its openings. It differs most obviously from A. hystricosa n. sp. in that the interior walls of zooidal peristomes are prickled, not smooth. Distribution. Recorded from two stations within coordinates 12.94712– 13.47733° N, 132.54418– 133.02290° W, at depth range 4824–5056 m.Published as part of Grischenko, Andrei V., Gordon, Dennis P. & Melnik, Viacheslav P., 2018, Bryozoa (Cyclostomata and Ctenostomata) from polymetallic nodules in the Russian exploration area, Clarion - Clipperton Fracture Zone, eastern Pacific Ocean-taxon novelty and implications of mining, pp. 1-91 in Zootaxa 4484 (1) on pages 41-43, DOI: 10.11646/zootaxa.4484.1.1, http://zenodo.org/record/143784
Vasopora ceramica Grischenko & Gordon & Melnik 2021, n. sp.
No full textVasopora ceramica n. sp. (Figs 2–4) Genus et species indet.: Grischenko, Gordon & Melnik 2018: p. 55, figs 36–38. Material examined. Holotype: ZIRAS 1 /50740, colony attached to nodule particle, YMG R. V. Gelendzhik cruise GLD4–19, Stn 421, 8 February 2021, 13.23408° N, 134.22180° W, 4809 m. Paratype 1: ZIRAS 2 /50738, colony (‘colony 1’ in Grischenko et al. 2018, p. 55, figs 36A, B, 37A, D, F, G), attached to nodule particle, YMG R. V. Gelendzhik cruise GLD4–11, Stn 211, 21 April 2012, 13.27820° N, 133.05707° W, 4846 m. Paratype 2: ZIRAS 3 /50739, colony (‘colony 2’ in Grischenko et al. 2018, p. 55, figs 36C, D, 37B, C, E, H, I), attached to nodule particle, YMG R. V. Gelendzhik cruise GLD4–12, Stn 255, 8 April 2013, 12.91588° N, 132.78325° W, 4801 m. Additional material: YMG18–01, Stn 38; YMG4–06, Stns 80, 81; YMG4–07, Stn 128; GLD4–09, Stns 183, 192; GLD4–12, Stn 272; YMG4–17, Stn 381; GLD4–19, Stn 421. Total specimens examined eleven. Etymology. Latinized form of Greek keramos, ceramic, alluding to the very smooth, glabrous surface of the colony stalk (column), resembling the surface of a ceramic vase. Gender feminine. Description. Colony erect, miniature, vasiform, with relatively convex capitulum on proportionately thin and tall column (Figs 2A–D, F, 3A, B). Capitulum:column height ratio 1:3. Capitulum with thin outer rim encircling eight radially orientated autozooidal peristomes and alveoli arranged along periphery (Fig. 2E, F), with centrally located incubation chamber on top (Figs 2E, F, 3A–C). Alveoli immediately inside calyx rim ovoid to slit-like. Much of remainder of capitulum comprising polygonal to subrounded alveoli, their combined rims giving a reticulated appearance (Fig. 2E, F). Entire skeletal surface of capitulum minutely densely granular to subspinulate (Figs 2G‒L, 3D‒H). Peristomes relatively short, eight in number, directed obliquely outwards at angle of c. 30–65° (Figs 2F, 3A–F). Peristomial rims of a few well-preserved peristomes with six to eight spine-like processes around margin (Figs 2F, 3A–D), each associated with longitudinal ridge on outside of peristomial base (Fig. 3D, E, J–L). Peristomial walls with sparse, simple communication pores (Figs 2G, 3D, E, J‒M). At higher magnification, outer surface constructed of irregular (Fig. 3L) or wedge-shaped crystallites (Fig. 3M). Gonozooid solitary, capacious, sac-like, domed, swollen, located centrally, with insignificant marginal shift relative to capitulum center, unidirectional (Figs 2E, F, I–L, 3A–C). Ooeciostome negligible, barely discernible, in form of very narrow, densely granulated band of calcification encircling ooeciopore and lacking pores (Fig. 2G, J, K). Ooeciopore (Fig. 2M, N) transversely subcircular, with flatter and straighter upper margin, located on slope of gonozooid, orientated perpendicularly relative to main colony axis, facing outwards (Figs 2F, I–K, 3D, E). Gonozooid with tiny circular pores concentrated on roof and less frequent on lateral and back sides (Fig. 2G‒L). Gonozooid covered by dense network of polygonal ridges (Fig. 2E, H) representing shallow alveoli, continuous with larger, deeper surrounding alveoli. Surface microstructure of gonozooid with imbricated irregular crystallites (Fig. 2O–Q). Column vase-like, elongated (Fig. 2A–D), 75% of colony height, narrowest in middle, flaring toward base (Fig. 3N) and capitulum. Entire column surface exterior-walled, smooth, glabrous, lacking pseudopores, with traces of regeneration preserved in form of weakly prominent rims with roughly uneven edges (Figs 2A–D, 3N). Skeletal microstructure (Fig. 3O) comprising planar-spherulitic surface fabric of closely appressed acicular to irregular sharp crystallites, clustered into parallel horizontal to oblique strips or fans parallel to wall surface. Upper margin of column (outer rim) even along whole perimeter (Figs 2A–D, 3A–E, G, H), smooth-surfaced, identically to main column surface, locally with gentle undulations in horizontal profile and very short straightening in vertical profile. Basal column margin deeply undulating over entire length (Figs 2A–D, 3N), following irregularities of substratum microrelief. Early astogeny (examined using non-type specimen, Fig. 4A–F) indicates protoecial dome, rather narrow in diameter (Fig. 4F), with erect ancestrular peristome arising from its entire roof (Fig. 4B, D, F), with first zooid also produced from dome adjacent to it (best seen in Fig. 4E). Multiple elongated to shortened trabeculae occupy periphery of expanded colony base to support continuing elevation and expansion, with greatly variable (tubular, cubical, oval to irregular) extrazooidal alveolar spaces or kenozooid-like chambers supporting base and stem (Fig. 4B, C). Measurements (mm). Holotype, ZIRAS 1/50740 (Figs 2, 3): Colony height 2.18; capitulum height 0.55; capitulum cross-section 1.16 × 1.06; column height 1.63; base at substratum cross-section 0.93 × 0.80; column narrowest cross-section 0.42 × 0.38; column upper margin (outer rim) cross-section 1.11 × 1.08. ZL 0.306 –0.507 (0.423 ± 0.058) (n = 8); PeL 0.141 –0.306 (0.240 ± 0.050) (n = 8); PeD 0.153 –0.173 (0.163 ± 0.007) (n = 8); ApL 0.143 –0.164 (0.153 ± 0.007) (n = 8); ApW 0.121 –0.134 (0.127 ± 0.004) (n = 8). Gonozooid (n = 1): GZL 0.504; GZW 0.341; GZH 0.357; OpL 0.111; OpW 0.132. Non-type specimen YMG4–17, Stn 381 (Fig. 4D, E): AnPrD 0.149 (n = 1); AnPeD 0.094 (n = 1). Remarks. Vasopora n. gen. clearly conforms to the characters of the rectangulate cyclostome family Alyonushkidae in general gross morphology, i.e. in possessing: 1) erect pedunculate colony with flaring capitulum of radially orientated autozooidal peristomes in one irregular level; 2) relatively large incubation chamber located in calyx center and surrounded by alveoli; 3) proximally tapering column to expanded base, incorporating vertically erect ancestrula with peristome arising from apex of protoecial dome (Fig. 4). At the same time, the new genus displays a combination of characters not previously observed in the two earlier-described alyonushkid genera. A comparison shows the following principal differences: 1) Species of Alyonushka and Calyssopora have no distinct structural boundary between the stalk (column) and capitulum, so that the stalk calcification is continuous with that of the capitulum and autozooidal peristomes in both of these taxa; in contrast, in Vasopora n. gen. the capitulum is encircled by a thin outer rim, present at all stages of astogeny, including ancestrulate and young infertile colonies (Grischenko et al. 2018, p. 58, fig. 38), conferring a consistent vasiform appearance, with a clear border between column and capitulum, where the autozooidal peristomes are always trapped inside the edge of the vase-like column. Among CCFZ fungiform cyclostomes, the sharp margin between stalk and capitulum is also known for Discantenna metallica Grischenko, Gordon & Melnik, 2018, but the latter species is tubuliporine, and clearly differs in having a stem with peristomes of feeding zooids between substratum and disk. 2) The reticulate appearance of the gonozooid roof and whole capitulum, giving the appearance of a network of ridges and contrasting with the smooth column, is unknown in any species of Alyonushka and Calyssopora. An alveolate calyx surface with a moderately developed trabeculate network is seen only in C. vasiformis (Grischenko et al. 2018, p. 50, fig. 31) but colonies of the latter species have a wholly dimpled surface over the capitulum and stalk. 3) Colonies of known species of Alyonushka and Calyssopora have a single type of microscopic calcification. Specifically, the entire outer colony surface is minutely prickled in every Alyonushka species, while in Calyssopora it is granular-tubercular (C. volcano), irregularly textured with minute dimples and granules (C. clarionensis), or dimpled (C. vasiformis), but in all cases the surface shows uniform topography for each given species. Microstructurally, the surface of these taxa is nearly identical, with imbricated platy crystallites (see for detail Grischenko et al. 2018, p. 38, fig. 22E; p. 42, fig. 25; p. 44, fig. 27E; p. 48, fig. 29H; p. 50, fig. 31I; p. 53, fig. 34J, K). In contrast, V. ceramica n. gen., n. sp. shows two different types of calcification with two clearly distinguishable forms of crystallites within colony: whereas surfaces of capitulum structures (peristomes, gonozooid, and trabeculate network) are minutely granular to subspinulate, the column surface is exterior-walled, smooth, glabrous and lacking pseudopores. Capitulum microstructure comprises polygonal wedge-shaped crystallites, while that of the column is planar-spherulitic with appressed acicular crystallites, clustered into horizontal to oblique belts or fans parallel to the surface. At the macro-level, these microstructural differences result in the strongly contrasting appearance of capitulum and column. In sum, the vivid contrast between the coarsely-surfaced reticulate capitulum and perfectly smooth glabrous column, with a clear boundary (rim) between, supplemented with two types of calcification and two forms of crystallites, makes Vasopora ceramica n. gen., n. sp. clearly distinguishable from other alyonushkids and hence a unique taxon among cyclostome genera described from the CCFZ. Distribution. The newly obtained holotype colony was collected from 13.23408° N, 134.22180° W at 4809 m. Overall, Vasopora ceramica n. gen., n. sp. so far occurs only within the Russian exploration area of the Clarion– Clipperton Fracture Zone from eleven stations (Fig. 1), bounded by coordinates 12.91588 – 13.82842 ° N, 129.06438– 134.73936° W, at 4725–5280 m depth.Published as part of Grischenko, Andrei V., Gordon, Dennis P. & Melnik, Viacheslav P., 2021, Vasopora ceramica n. gen., n. sp. - a new abyssal cyclostome bryozoan from polymetallic nodules in the Russian exploration area, Clarion-Clipperton Fracture Zone, eastern Pacific Ocean, pp. 444-452 in Zootaxa 5047 (4) on pages 446-450, DOI: 10.11646/zootaxa.5047.4.4, http://zenodo.org/record/554305
Frontohornera frontalis Grischenko & Gordon & Melnik 2018, n. sp.
No full textFrontohornera frontalis n. sp. (Figs 2J, K, 16–18) Material examined. Holotype: ZIRAS 1/50707, colony detached from nodule, YMG R.V. Yuzhmorgeologiya cruise YMG4–13, Stn 292, 27 July 2014, 13.03353° N, 132.49292° W, 4829 m. Paratype: ZIRAS 2/50708, colony attached to nodule particle, YMG R.V. Gelendzhik cruise GLD4–11, Stn 210, 20 April 2012, 13.35817° N, 133.27183° W, 4815 m. Additional material: YMG4–07, Stn 124; GLD4–11, Stn 215; YMG4–14, Stns 329, 334. Total specimens examined six. Etymology. Latin, frontalis, frontal, alluding to the frontally borne gonozooid. Description. Colony erect, white, to 2.81 mm high, 6.76 mm broad, dichotomously branching once in a single plane (Fig. 16A, B), or with short additional bifurcation to produce a third, short branch near colony center (Fig. 18G, H). Stem diameter 0.32 × 0.37 mm, widening to colony base (0.66–0.76 mm). With distinct frontal and abfrontal faces (Fig. 16), entire surface interior-walled, textured irregularly with minute dimples, granules, ridges and furrows (Fig. 17A–G), with longitudinal linearities only on stem of colony; conspicuous ribbing (nervi) and grooves (sulci) lacking. Pores simple, tiny, sparse. Autozooids in 2–4 series, their peristomes produced frontally upwards, relatively short along frontolateral and central parts of branch, longest along abfrontolateral margin, with simple circular apertures, no apertural spines (Fig. 17A–F, I). Peristomes somewhat dimorphic (Fig. 17F), short and uniformly tubular with circular apertures in central face of branches, but strongly elongated, with aperture having shape of teardrop, isosceles triangle or irregular oval along branch margins. Peristome wall interiors with short, thin spinules proximal to aperture (Fig. 17I). Cancelli most numerous on central part of branch distal to gonozooid (Figs 16A, 17A, E, J), otherwise sparse, shallow, of varying size. Abfrontal face of colony with outlines of autozooidal tubes (Figs 16B, 17G), their longitudinal contours converging proximad. Gonozooid frontally borne, adjacent to second dichotomy (Fig. 16A), subglobular, surface like that of colony but with slightly denser prickled granules (Fig. 17H, J, K), frontal peak and distal sides of chamber converging towards short ooeciostome that curves frontalwards (Fig.17H, J, K), ooeciopore transversely oval (Fig. 17L). Ancestrular zooid not seen in isolation; earliest growth stages encountered show lowest peristome of colony (presumed ancestrular peristome), which appears to be wholly erect, though concealed within basal skirt of extrazooidal calcification (Fig. 18G, I). Peristome of daughter zooid above it in series, but in another colony ancestrular and two daughter peristomes occur as cluster of three (Fig. 18B). Measurements (mm). Holotype, ZIRAS 1/50707 (Fig. 16A, B): ZL 0.569–0.763 (0.663 ± 0.071). Branch center: PeL 0.072–0.197 (0.122 ± 0.042); PeD 0.141–0.162 (0.153 ± 0.008); ApD 0.129–0.141 (0.137 ± 0.004). Branch margin: PeL 0.194–0.526 (0.374 ± 0.102); PeD 0.110–0.146 (0.135 ± 0.011); ApL 0.132–0.176 (0.156 ± 0.016) (n = 7); ApW 0.122–0.147 (0.132 ± 0.008) (n = 7). Gonozooid (n = 1): GZL 0.744; GZW 0.511; GZH = 0.377; OsL 0.167; OsW 0.132; OsH 0.196; OpL 0.073; OpW 0.071. Non-type specimen GLD4–11, Stn 210 (Fig. 18G–I): AnPeD 0.144 (n = 1). Remarks. Frontohornera frontalis n. sp. is represented in the collection by six colonies of varying ages and sizes. Only one reproductively mature colony was encountered. All were found attached to polymetallic nodules. Distribution. Recorded from six stations within coordinates 13.03353– 14.29353° N, 131.87598– 134.23457° W, at depth range 4815–5166 m.Published as part of Grischenko, Andrei V., Gordon, Dennis P. & Melnik, Viacheslav P., 2018, Bryozoa (Cyclostomata and Ctenostomata) from polymetallic nodules in the Russian exploration area, Clarion - Clipperton Fracture Zone, eastern Pacific Ocean-taxon novelty and implications of mining, pp. 1-91 in Zootaxa 4484 (1) on pages 29-32, DOI: 10.11646/zootaxa.4484.1.1, http://zenodo.org/record/143784
Haywardozoon pacificum Grischenko & Gordon & Melnik 2018, n. sp.
No full textHaywardozoon pacificum n. sp. (Figs 47, 48) Material examined. Holotype: ZIRAS 1/50726, colony encrusting tube of serpulid polychaete detached from nodule, YMG R.V. Yuzhmorgeologiya cruise YMG4–04, Stn 39, 16 August 2005, 13.61415° N, 130.82158° W, 5017 m. Additional material: YMG4–07, Stns 134, 143; GLD4–11, Stns 214, 220; GLD4–12, Stns 245, 267; YMG4–14, Stn 322. Total specimens examined eight. Etymology. Alluding to the first description of the genus in the Pacific Ocean. Description. Colony encrusting, diffuse, comprising up to c. 12 large zooids, partly uniserially arranged and disjunct (Figs 47, 48), adjacent zooids connected distally and laterally by very small contact points; highly transparent and apparently colorless in life. Zooids generally mostly elongated, their lateral outlines weakly convex to subparallel or even slightly diverging; bilaterally symmetrical or one side extending outwards as a triangular skirt. Daughter zooids budded distolaterally. Membranous frontal wall gently rising to highest point of zooid at orifice (Fig. 47G). Orifice wider than long (Figs 47I, J, 48G), having slightly thickened cuticularized rim with two components—proximal rim more or less transversely C-shaped, concave on inner side; distal rim more or less straight but produced proximally as D-shaped flap that superficially resembles operculum and fits into concavity of proximal rim; edge of flap slightly thickened (Figs 48G, H). Vestibule more or less parallel-sided, a little longer than broad, 28–33% polypide length, with strongly developed parieto-diaphragmatic musculature at proximolateral corners (Fig. 47I, J). Vestibule 0.097–0.123 mm long; retracted tentacle crown 0.265–0.311 mm long, tentacle number not determined. No stomach gizzard. Small brown bodies or fragments of brown bodies retained in cystid (Fig. 47I, J). Anchor point of polypide retractor muscles not clearly seen. One very small oval zooid encountered that may be ancestrula, very close to proximal curved ‘tail’ of large zooid that may have budded from it (Fig. 48I). Orifice of small zooid (Fig. 48J) identical in form to that of large zooids). Measurements (mm). Holotype, ZIRAS 1/50726 (Figs 47, 48): ZL 0.703–1.450 (1.048 ± 0.211); ZW 0.438–0.852 (0.714 ± 0.117); OrL 0.088–0.140 (0.120 ± 0.018); OrW 0.150–0.203 (0.172 ± 0.019). Ancestrula (n = 1): AnL 0.322; AnW 0.221; AnOrL 0.027; AnOrW 0.059. Remarks. We follow Jebram (1986) in including Haywardozoidae in superfamily Hislopioidea, and Reverter- Gil et al. (2016) concerning the emended spelling of the family name. Our material conforms to the overall characters of the two described Atlantic species of Haywardozoon, especially H. inarmatum, which has a similar budding pattern and zooid shape, but from which it differs in details of the orifice. D’Hondt (1983) characterized the polypide of Haywardozoon species as “minute … inhabiting only a very small portion of the zoecial cavity”, which is not the case in H. pacificum n. sp. The CCZ colonies were found only on tubes of serpulid polychaetes attached to nodules. Distribution. Recorded from eight stations within coordinates 12.26676– 13.61415° N, 130.82158– 134.59811° W, at depth range 4741–5050 m.Published as part of Grischenko, Andrei V., Gordon, Dennis P. & Melnik, Viacheslav P., 2018, Bryozoa (Cyclostomata and Ctenostomata) from polymetallic nodules in the Russian exploration area, Clarion - Clipperton Fracture Zone, eastern Pacific Ocean-taxon novelty and implications of mining, pp. 1-91 in Zootaxa 4484 (1) on pages 69-74, DOI: 10.11646/zootaxa.4484.1.1, http://zenodo.org/record/143784
Pandanipora helix Grischenko & Gordon & Melnik 2018, n. sp.
No full textPandanipora helix n. sp. (Figs 2A–E, 3–5) ‘? Incertae sedis no. 4’ Harmelin & d’Hondt 1982: 13, pl. 4, figs 1–2; d’Hondt & Schopf 1985: 950, pl. 8, fig. 5. ‘Cyclostome indéterminé’ d’Hondt & Schopf 1985: 949, pl. 8, fig. 3. Material examined. Holotype: ZIRAS 1/50667, colony detached from nodule, YMG R.V. Gelendzhik cruise GLD4–12, Stn 238, 11 March 2013, 13.44587° N, 132.91008° W, 4772 m. Paratype 1: ZIRAS 2/50668, colony detached from nodule, YMG R.V. Yuzhmorgeologiya cruise YMG4–04, Stn 61, 5 September 2005, 13.59717° N, 130.65212° W, 5008 m. Paratype 2: ZIRAS 3/50669, colony detached from nodule, YMG R.V. Gelendzhik cruise GLD4–08, Stn 153, 26 July 2009, 13.15205° N, 133.89166° W, 5014 m. Paratype 3: ZIRAS 4/50670, colony detached from nodule, YMG R.V. Gelendzhik cruise GLD4–12, Stn 259, 10 April 2013, 12.86148° N, 132.82182° W, 4910 m. Paratype 4: ZIRAS 5/50671, colony detached from nodule, YMG R.V. Gelendzhik cruise GLD4–09, Stn 176, 24 December 2010, 12.93062° N, 133.56097° W, 4865 m. Paratype 5: ZIRAS 6/50672, colony attached to nodule particle, YMG R.V. Gelendzhik cruise GLD4–09, Stn 190, 3 January 2011, 13.38432° N, 133.51833° W, 4838 m. Additional material: YMG18–01, Stns 17, 23, 27, 32; YMG4–04, Stns 52, 53, 54, 55; YMG4–06, Stns 65, 68, 73, 85, 94, 96, 105, 106, 110, 114; YMG4–07, Stns 116, 117, 120, 125, 134, 136, 141, 143; GLD4–08, Stns 144, 145, 146, 150, 154, 155, 157, 160, 161, 164; GLD4–09, Stns 165, 166, 169, 170, 173, 174, 181, 185, 193, 194, 197, 199; GLD4–11, Stns 212, 214, 215, 217, 218, 219, 224, 225, 226, 227, 231, 233; GLD4–12, Stns 235, 236, 245, 246, 253, 255, 258, 260, 262, 263, 264, 265, 272; YMG4–13, Stns 275, 276, 282, 285, 289, 292, 293, 295, 305, 308, 310, 319, 321; YMG4–14, Stns 324, 326, 328, 329, 330, 331, 332, 334, 335, 336, 338, 340, 342, 343, 346, 349, 350, 352, 354, 356, 358, 359, 361, 363, 364, 365. Total specimens examined 203. Etymology. Latin and Greek, helix, a coil or spiral, alluding to the common form of the colony; used as a noun in apposition. Description. Colony uniserial, semi-erect, white, comprising chain of zooids borne above solid substratum by elongated prop-like supports (Figs 2A–E, 3A–G), typically one (very rarely two) per zooid, body cavity of zooid continuous with that of prop (Fig. 5E). Zooidal chain varied in disposition, either straight and more or less parallel to substratum or often ascending as open helicospiral, with up to 2.5 turns (Fig. 3C) depending on age; many colonies have form somewhat intermediate between these extremes. Branching of uniserial stem uncommon, typically near colony origin, rarely further along stem (Fig. 3E). Maximum colony length or diameter 12.60 mm; maximum colony height 3.74 mm. Most zooids seen in colonies ~24 (holotype; Fig. 3A, C) and 26 (Fig. 2E). Autozooids comprising proximal and distal components; axial proximal component forms part of continuous uniserial stem of colony, while distal component forms erect peristome of varying length. Frontal peristomial surface typically curving obliquely frontalwards from axial frontal surface; distal peristomial surface forming much sharper angle (up to 90°) with frontal wall of daughter zooid. Autozooidal surface wholly gymnocystal (i.e. exterior-walled), with weak longitudinal and transverse striae or wrinkles (Figs 4B, C, J, K), latter more apparent in zooidal peristomes; at higher magnification exterior surface made up of wall-perpendicular needle-like crystallites (Fig. 4P, Q). Very tiny simple pseudopores occurring sparsely in zooidal walls (Fig. 4O–Q). Peristomial opening circular, very thin-walled (Figs 4J–M), becoming thicker through accretion of additional layers of crystallites. Interior surface of peristomes lined by distally imbricated foliated fabric of wedge-shaped crystallites (Fig. 4N) that tend to be shorter and chunkier in proximal axial walls of zooids, especially around interior openings of pseudopores (Fig. 4D). Zooidal axial and peristomial lengths generally similar, but can be independently variable, with peristomes slightly shorter than, or up to more than twice length of proximal axial portion of zooid (Fig. 3G). Budding of daughter zooids achieved by development of partition from floor of parent zooid (Fig. 4B, C) that slopes frontalwards under elevating peristomial portion, with completed parent zooids overlapping proximal portion of daughter zooids; thus parts of 2–3 zooidal chambers seen in transverse section of stem (Fig. 4A). In lessattenuated colonies with tight helicospiral form, axis becomes thicker (Fig. 3A, B) and budding sites are condensed. Prop-like supports elevate colony after its founding. These greatly variable in size and form. Some props have widened (up to three times wider than their mean diameter) bases at their points of contact with substratum. Typically, one prop per autozooid, originating near point where internal partitioning of daughter autozooid takes place (Figs 4A, 5E); sometimes additional prop interpolated in series (e.g. Fig. 3G). Props can be length of peristome or very much longer and almost filiform (Fig. 3B). Short, stumpy props that do not reach substratum appear to represent repaired broken props. Where they encounter substratum, proximal ends of props have short branches that splay out over irregularities (Fig. 5A–C). Tiny sparse pseudopores occur in prop walls (Fig. 5F). Gonozooid not seen. Ancestrula erect (Fig. 5G–L). Protoecium short, rounded, squat, imperforate, broader than peristome that emerges from its dome, with scarcely any differentiation in calcification. Peristome typically bent in direction of initial colony growth. Measurements (mm). Holotype, ZIRAS 1/50667 (Fig. 3A, C): Colony height 3.74, length 2.91, width 2.58 (L × W = helix in frontal view); ZL 1.373–1.918 (1.628 ± 0.181) (n = 8); PrL 0.458–2.443 (1.518 ± 0.999) (n = 3); PrD 0.120–0.186 (0.145 ± 0.035) (n = 3); PeL 0.243–0.442 (0.318 ± 0.067) (n = 8); PeD 0.177–0.186 (0.181 ± 0.003) (n = 4); ApL 0.170–0.178 (0.173 ± 0.003) (n = 4); ApW 0.162–0.170 (0.165 ± 0.004) (n = 4). Paratype 1, ZIRAS 2/50668 (Fig. 3B): Colony height 3.39, length 6.41, width 4.88 (L × W = size of coil in frontal view); ZL 1.443–2.288 (1.989 ± 0.287) (n = 6); PrL 1.211–3.165 (2.373 ± 0.672) (n = 6); PrD 0.073–0.104 (0.082 ± 0.012) (n = 6); PeL 0.516–0.893 (0.776 ± 0.137) (n = 6); PeD 0.174–0.185 (0.180 ± 0.004) (n = 6); ApL 0.165–0.173 (0.168 ± 0.003) (n = 6); ApW 0.155–0.164 (0.160 ± 0.004) (n = 6). Paratype 5, ZIRAS 6/50672 (Fig. 3G): Colony height 2.52, length 6.92; ZL 1.823–2.838 (2.261 ± 0.338) (n = 6); PrL 0.628–0.993 (0.834 ± 0.149) (n = 6); PrD 0.083–0.138 (0.108 ± 0.019) (n = 6); PeL 0.924–1.581 (1.214 ± 0.244) (n = 6); PeD 0.178–0.198 (0.190 ± 0.007) (n = 6); ApL 0.173–0.185 (0.180 ± 0.004) (n = 6); ApW 0.161–0.187 (0.174 ± 0.009) (n = 6). Non-type specimen YMG4–14, Stn 326 (Fig. 5G–I): AnPeD 0.156 (n = 1). Remarks. In the collections examined for this study, Pandanipora helix n. sp. is represented by 203 colonies, which makes it all the more remarkable that not one bears a gonozooid. One possibility is that it never has gonozooids, but, among living cyclostomes, only species of Cinctiporidae unequivocally lack such structures (Boardman et al. 1992). Insofar as cinctiporids have exceptionally large autozooids, it appears likely that oogenesis and embryo formation takes place within them (see Schwaha et al. 2018). Zooidal size in Pandanipora helix n. sp. is not exceptional and there seems no reason that a peristomial gonozooid like that in Peristomatopora should not be present. Gonozooids were also notably absent from most colonies in the large collection of Antarctic cyclostomes studied by Ostrovsky & Taylor (1996) and Ostrovsky (1998a). What is striking is that non-fertile colonies otherwise were of the same size as those bearing gonozooids, thus supporting the idea that incubation chambers will develop only if a colony is fertilized by alien sperm (Ryland 1996). In other words, sperm limitation may be a reason for the lack of gonozooids in many colonies. Experiments conducted on two cyclostome species by Jenkins et al. (2015) showed restrained female investment in the absence of mating opportunity; either the production of female zooids and progeny is much reduced in reproductive isolation, or development of gonozooids begins, but ceases further development in the absence of mating opportunity. Another possibility in Pandanipora helix is that incubation chambers are produced but are shed after release of embryos. Alternatively, gonozooids may be very fragile, and lost during the process of collection from the seafloor and subsequent processing of the polymetallic nodules. Harmelin & d’Hondt (1982) illustrated an unnamed species from 3392–3429 m depth off the coast of Surinam that conforms to the characters of the genus. D’Hondt & Schopf (1985) reported this same species again from 943 m off Recife and 3459–3783 m on the equatorial mid-Atlantic Ridge. What they interpreted as ‘épines autozoéciales’ appear in their illustrations to be broken prop-like supports, of proportionately smaller diameter than in P. helix n. sp. Even closer to P. helix in appearance, and almost certainly conspecific, was a colony from 6065–6079 m in the central North Pacific north of the Hawaiian seamount chain. Based on this evidence, it appears likely that P. helix n. sp. may be fairly widespread in the abyssal north Central Pacific, with an undescribed sibling species in the abyssal tropical Atlantic. Our material shows up to five brown bodies retained in zooidal chambers (Fig. 5E), indicating multiple regression and regeneration of polypides. Distribution. Recorded from 118 stations within coordinates 12.26676– 14.64985° N, 129.08802– 134.67060° W, at depth range 4677–5280 m.Published as part of Grischenko, Andrei V., Gordon, Dennis P. & Melnik, Viacheslav P., 2018, Bryozoa (Cyclostomata and Ctenostomata) from polymetallic nodules in the Russian exploration area, Clarion - Clipperton Fracture Zone, eastern Pacific Ocean-taxon novelty and implications of mining, pp. 1-91 in Zootaxa 4484 (1) on pages 9-15, DOI: 10.11646/zootaxa.4484.1.1, http://zenodo.org/record/143784
Calyssopora vasiformis Grischenko & Gordon & Melnik 2018, n. sp.
No full text<i>Calyssopora vasiformis</i> n. sp. <p>(Figs 31, 32)</p> <p> <b>Material examined.</b> <i>Holotype</i>: ZIRAS 1/50717, colony detached from nodule, YMG R.V. <i>Gelendzhik</i> cruise GLD4–11, Stn 203, 17 April 2012, 13.45102° N, 133.17315° W, 4812 m. <i>Additional material</i>: GLD4–11, Stns 201, 228. Total specimens examined three.</p> <p> <b>Etymology.</b> Latin, <i>vas</i>, vessel, and <i>forma</i>, shape, alluding to the form of the colony.</p> <p> <b>Description.</b> Colony erect, pedunculate, with autozooidal peristomes radiating outwards around periphery of radially symmetrical capitulum, up to maximum of six peristomes in single whorl (Fig. 31A–E, G, H), with additional non-peristomate alveolar openings below. Column longer than capitulum, attached by disk-like (Fig. 31A–D, H) or smaller base (Fig. 32B–D, F–H), depending on size. Colony surface malleated (Fig. 31A–D, G) except for proximal third or half of column, which has narrow ridges and furrows; each malleation (dimple) surrounded by distinct angular ridge (Fig. 31J, K); pores simple, very sparse (Fig. 31G, J, K). Surface ultrastructure generally of imbricated platy crystallites or these smaller, irregularly arranged and lacking preferred growth direction. Capitulum shallowly calyciform in immature colony (Fig. 32H), calyx center with trabeculae and alveoli (Fig. 32A, E).</p> <p>Autozooidal peristomes short, in single series; apertures subrounded, facing obliquely outwards, their rims slightly irregular but entire. Inner surface of peristome tubes smooth to lightly textured, no pustules or spinules (Fig. 31G, J).</p> <p>Gonozooid solitary, capacious, occupying calyx center (Fig. 31E, H, J), weakly domed (Fig. 31A–D, G), ooeciostome almost non-existent, with proportionally large circular ooeciopore in center (Fig. 31I). Gonozooid surface malleated frontally, with at least one pore in each dimple, periphery of chamber alveolate, each alveolus with pore (Fig. 31E, F, J).</p> <p>Ancestrula and very small colony stages not seen. Smallest colony encountered had perhaps four functioning peristomes and others developing, its center comprising small triangular shelf with small alveoli (Fig. 32A).</p> <p> <b>Measurements (mm).</b> Holotype, ZIRAS 1/50717 (Fig. 31): Colony height 2.55; capitulum 1.08 × 0.85; base at substratum 0.73 × 0.66; stalk minimal diameter 0.28; ZL 0.275–0.325 (0.294 ± 0.019) (<i>n</i> = 6); PeL 0.188–0.238 (0.217 ± 0.020) (<i>n</i> = 6); PeD 0.151–0.178 (0.161 ± 0.009) (<i>n</i> = 6); ApL 0.148–0.173 (0.156 ± 0.009) (<i>n</i> = 6); ApW 0.103–0.125 (0.118 ± 0.008) (<i>n</i> = 6); OpL 0.064 (<i>n</i> = 1); OpW 0.061 (<i>n</i> = 1).</p> <p> <b>Remarks.</b> The gonozooid in <i>Calyssopora vasiformis</i> <b>n. sp.</b> is similar to that in the type species <i>C. volcano</i> <b>n. sp.</b>, but the colony surface is malleated, as in <i>Rallocytus ridiculus</i> <b>n. gen.</b>, <b>n. sp.</b> (below).</p> <p> <b>Distribution.</b> Recorded from three stations within coordinates 12.61497– 13.55908° N, 133.04948– 133.18555° W, at depth range 4806–4909 m.</p>Published as part of <i>Grischenko, Andrei V., Gordon, Dennis P. & Melnik, Viacheslav P., 2018, Bryozoa (Cyclostomata and Ctenostomata) from polymetallic nodules in the Russian exploration area, Clarion - Clipperton Fracture Zone, eastern Pacific Ocean-taxon novelty and implications of mining, pp. 1-91 in Zootaxa 4484 (1)</i> on pages 46-51, DOI: 10.11646/zootaxa.4484.1.1, <a href="http://zenodo.org/record/1437848">http://zenodo.org/record/1437848</a>
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