Calyssopora volcano, Grischenko & Gordon & Melnik, 2018

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, Zootaxa 4484 (1), pp. 1-91: 45-46

publication ID

https://doi.org/10.11646/zootaxa.4484.1.1

publication LSID

lsid:zoobank.org:pub:D66524CF-9C6D-4DF4-8CA2-B2C9708CF5FD

persistent identifier

http://treatment.plazi.org/id/521587E4-561E-552A-09EE-FC16884FFC23

treatment provided by

Plazi

scientific name

Calyssopora volcano
status

n. sp.

Calyssopora volcano   n. sp.

( Figs 2M View FIGURE 2 , 28–30 View FIGURE 28 View FIGURE 29 View FIGURE 30 )

Material examined. Holotype: ZIRAS 1/50714, colony attached to nodule particle, YMG R.V. Yuzhmorgeologiya cruise YMG4–14, Stn 357, 18 January 2016, 14.03237° N, 131.74563° W, 5073 m. Paratype 1: ZIRAS 2/50715, colony attached to nodule particle, YMG R.V. Gelendzhik cruise GLD4–12, Stn 251, 6 April 2013, 12.80823° N, 132.69682° W, 4837 m. Paratype 2: ZIRAS 3/50716, colony attached to nodule particle, YMG R.V. Yuzhmorgeologiya cruise YMG4–14, Stn 325, 20 December 2015, 13.58832° N, 131.68838° W, 5031 m. Additional material: YMG18–01, Stns 7, 15, 24, 33; YMG4–04, Stn 57; YMG4–06, Stns 70, 92, 99, 101, 103; YMG4–07, Stn 139; GLD4–09, Stns 173, 178, 185, 198; GLD4–11, Stn 216; GLD4–12, Stn 271; YMG4–13, Stns 274, 283, 291, 300; YMG4–14, Stns 348, 358. Total specimens examined 27.

Etymology. Anglicized spelling of the Italian vulcano, alluding to the volcano-like gonozooid with its craterlike ooeciopore; used as a noun in apposition.

Description. Colony erect, thickly pedunculate, with autozooidal peristomes radiating outwards around periphery of capitulum ( Fig. 28 View FIGURE 28 ), up to maximum of 22 peristomes in single irregular whorl. Skeletal surface of column with weakly defined ridges and furrows, granular-tubercular ( Fig. 29A –C View FIGURE 29 ), with sparse pores; surface ultrastructure with irregularly arranged crystallites lacking obvious preferred growth direction ( Fig. 29H View FIGURE 29 ). Capitulum of submature colony infundibuliform ( Fig. 30L View FIGURE 30 ), bottom of funnel comprising deep alveolar chambers delimited by trabeculae ( Fig. 30O View FIGURE 30 ). Additional thin walls cross gaps between adjacent peristomes at colony periphery where additional autozooidal chambers develop to fill vacancies in whorl as colony expands ( Figs 29J View FIGURE 29 , 30A, I, O View FIGURE 30 ); some of these openings seem to represent adjacent extrazooidal spaces, their openings narrowed in mature colony ( Fig. 29B View FIGURE 29 ). Increasing calcification reduces openings in calyx center to expanding porous platform that serves as irregular open ‘floor’ to gonozooid(s) ( Fig. 30O View FIGURE 30 ).

Autozooidal peristomes in single subregular series, skeletal surface like that of column, with sparse, simple pores ( Fig. 29G View FIGURE 29 ) having irregular outline, tending to be in single longitudinal series on lower side ( Fig. 29L View FIGURE 29 ). Developing apertures slightly irregular, subrounded ( Fig. 29A, K View FIGURE 29 ) or having bilateral symmetry, opening obliquely outwards and downwards ( Fig. 29L View FIGURE 29 ). No spinules or prickles on inner surface of peristome tubes ( Fig. 29K, L View FIGURE 29 ).

Gonozooid large and capacious ( Fig. 28A, B View FIGURE 28 ), 1–2 per mature colony ( Fig. 28C, D View FIGURE 28 ). Floor of gonozooid not discrete and continuous. If solo, gonozooid in center of calyx or to one side, chamber roof sloping upwards to ooeciostome ( Fig. 29A –D View FIGURE 29 ), resembling volcanic cone in profile, with lateral ridges and furrows and porous cancelli that are mostly on periphery of gonozooid ( Fig. 29D View FIGURE 29 ); ooeciopore variably elevated, subcircular to suboval ( Fig. 28A, C, E View FIGURE 28 ). Surface microstructure of gonozooid like that of column and zooidal peristomes, with weak imbrication of irregular crystallites ( Fig. 29H View FIGURE 29 ).

Ancestrula not seen in isolation, but evidently erect judging from smallest (four-zooid) colony stages seen ( Fig. 30A, B View FIGURE 30 ). Trabeculae form in center of developing colony to support colony elevation and expansion, with extrazooidal alveolar spaces between trabeculae ( Fig. 30A, C, I, K, M, O View FIGURE 30 ).

Measurements (mm). Holotype, ZIRAS 1/50714 ( Fig. 28A, B View FIGURE 28 ): Colony height 1.78; capitulum 2.07 × 1.98; base at substratum 0.85 × 0.93 with narrowest cross-section 0.60 × 0.64; ZL 0.591–0.980 (0.809 ± 0.122); PeL 0.372–0.597 (0.492 ± 0.069); PeD 0.137–0.177 (0.155 ± 0.013); ApL 0.152–0.185 (0.172 ± 0.011); ApW 0.128–0.153 (0.138 ± 0.009). Gonozooid (n = 1): GZL 0.644; GZW 0.817; OsL 0.155; OsW 0.127; OsH 0.138; OpL 0.133; OpW 0.119.

Remarks. Calyssopora volcano   n. sp. differs from Calyssopora vasiformis   n. sp. (below) in overall form and the number of peristomes, and from Calyssopora clarionensis   n. sp., in having volcaniform gonozooids in which the frontal surface rises to a frontally facing ooeciostome with a crater-like ooeciopore. The gonozooid in A. clarionensis   is rather more bulging than volcaniform, and the ooeciostome is strongly curved and hood-like.

Dartevellopora granulosa Gordon & Taylor, 2010   was only doubtfully included in Dartevellopora   when described. In some respects, it resembles the species of Calyssopora   , but differs in that there is a clear differentiation between a smoothly spreading skirt-like base and pustulose erect part of the column. The center of its capitulum is less calyciform than in Calyssopora   , comprising a subhorizontal platform with evenly distributed circular pores, unlike the open alveolate and trabecular mesh of Calyssopora   . Until fertile colonies of D. granulosa   are found, its generic attribution must remain problematic.

Distribution. Recorded from 26 stations within coordinates 12.51953– 14.16490° N, 129.04471– 134.60008° W, at depth range 4672–5149 m.

Kingdom

Animalia

Phylum

Bryozoa

Class

Stenolaemata

Order

Cyclostomatida

Family

Lichenoporidae

Genus

Calyssopora

Loc

Calyssopora volcano

Grischenko, Andrei V., Gordon, Dennis P. & Melnik, Viacheslav P. 2018
2018
Loc

Dartevellopora

Grischenko & Gordon & Melnik 2018
2018
Loc

Calyssopora

Grischenko & Gordon & Melnik 2018
2018
Loc

Calyssopora

Grischenko & Gordon & Melnik 2018
2018
Loc

Calyssopora

Grischenko & Gordon & Melnik 2018
2018
Loc

Dartevellopora granulosa

Gordon & Taylor 2010
2010
Loc

D. granulosa

Gordon & Taylor 2010
2010