Geodia aff. megastrella sensu Van Soest & Stentoft, 1988: 14 Deep-water sponges (Porifera) from Bonaire and Klein Curaçao, Southern Caribbean Van Soest, Rob W. M. Meesters, Erik H. W. G. Becking, Leontine E. Zootaxa 2014 2014-10-29 3878 5 401 443 Van Soest & Meesters & Becking, 2014 Van Soest & Meesters & Becking 2014 [151,403,1563,1589] Demospongiae Geodiidae Geodia Animalia Astrophorida 11 412 Porifera species curacaoensis sp. nov.   Figures 8a–k      Geodiaaff. megastrellasensu Van Soest & Stentoft, 1988: 14, pl. 11 figs 1–4, text-fig. 4 (not: Carter, 1876, nec sensu Topsent, 1911, 1928)    Material examined.  Holotype: RMNHPor. 9260, Caribbean Netherlands, Klein Curacao, off SW coast (Dive 1), 11.9821°N 68.6452°W, on a coral rock wall at  156 m, coll. L.E. Becking& E. Meesters, field nr. CURASUB13-09/ BDR005,  27 May 2013.   Forcomparison:  Geodiacf. megastrellasensu Van Soest & Stentoft, 1988, ZMAPor. 05272, Barbados, off Paynes Bay,  144–153 m,  11 August 1978.    Description.Small sphere ( Fig. 8a) of 5.5 cmdiameter (two fragments were preserved, one of 5 x 2.5 x 2 cm, a second of 4 x 2.5 x 2 cm). Surface generally smooth but with patches of long hair-like spicules distributed over the entire surface. Oscules crowded on top in a sieve plate. Color white grey around, but with upper half and sieveplate dark red. Cortex can crack easily, and choanosome is pulpy.   Skeleton.Cortex ( Fig. 8b) consisting of a layer of sterrasters 300–500 µmin thickness, carried by the cladi of radially arranged ortho/plagiotriaenes, anatriaenes and oxeas. Small short oxeotes and abundant small asters are distributed in the peripheral regions of the cortex among the cladi of the triaenes. Choanosomal skeleton a confused mass of oxeas and small aster microscleres.   Spicules.Ortho/plagiotriaenes, anatriaenes, oxeas, cortical oxeotes, sterrasters, oxyasters, strongylasters. Ortho/plagiotriaenes ( Fig. 8c), (cladi curved downwards, so technically they are closer to orthotriaenes than to plagiotriaenes, but the cladi are not exactly at right angles to the shaft). They are not very common and were invariably broken in the slides. From measurements from thick sections it appeared that the shaft length is up to approximately 4200 µm(usually smaller), shaft width 50–90 µm, cladomes 320–550 µm, cladi 160–270 x 60 µm. Anatriaenes ( Figs. 8d, 8d 1), shaft length 1500–2000 µm, shaft width 20– 25– 30 µm, cladomes 120– 152– 180 µm, cladi 70– 93– 120 µmx 20– 28– 50 µm. Oxeas ( Fig. 8e, 8e 1), usually broken in the slides, they are mostly around 4000 µmx 30 µm(thick section measurements). Cortical oxeotes ( Fig. 8f, 8f 1), slightly different at both ends, 320– 380–480 x 7.5– 10–12.5. Sterrasters ( Fig. 8g), slightly oval, 70– 94–110 x 70– 78–85, individual rosettes approximately 5 µmin diameter with larger spines numbering 4–6. Large oxyasters ( Figs. 8h–i), diameter 15– 22– 28 µm, number of rays 6–8. Small oxyasters ( Figs. 8h, 8j), diameter 10– 12– 18 µm, number of rays 6–12. Strongylasters ( Figs. 8h, 8k), diameter 5– 6.7– 10 µm.    Ecology and distribution.One specimen collected on carbonate rock wall just below the mesophotic zone at Klein Curaçao.    Etymology.Named after the typelocality, (Klein) Curaçao.    Remarks.It is likely that this species was recorded from Barbadosby Van Soest & Stentoft (1988: 14)as  Geodiacf. megastrella Carter, 1876. We reexamined this material. It differs from Carter’s Portuguese material in the presence of short cortical oxeas and the size of the oxyasters, which are only half the size in the Barbadosspecimen (and in our new species). The shape of the Barbadosmaterial differs from that of the holotypeof our new species in being more elaborate and irregular, but its size is also larger (10 x 10 x 7 cm) and it is not unusual for geodiid species to have a globular shape when young and more irregular when older. In the spiculation of the Barbadosspecimens only one feature seemed to differ, the length of the cortical oxeotes, given as 150 x 3–4 µmin Van Soest & Stentoft (1988: 14). When we reexamined this, we found that variation is large and many of the cortical oxeotes were in the range of 200–300 x 5–6 µmand only few were as small as 150 µm. We assume that the Barbadosmaterial and the present specimen are conspecific as all other features match closely. On paper our new species appears rather close to  Geodia gibberosaLamarck, 1814as extensively redescribed by Cárdenas et al.2009, but habit, length of the oxeas and the form, ray number and ornamentation of the oxyasters are clearly different in the two species.  G. gibberosawas also reported from deep water ( Barbados, cf. Van Soest & Stentoft 1988). Of the  Geodiaspeciesrecorded from the Central West Atlantic,  G. tumulosa Bowerbank, 1872appears close to our new species, but it differs in overall shape and in having protriaenes in addition to ortho- and anatriaenes. Furthermore the sterrasters are about half the size of those of our new species, and the largest oxyasters are twice as large as those of our new species. Most other species reported from the region differ more clearly by lacking cortical oxeas (  G. australis Da Silva & Mothes, 2000,  G. riograndensis Da Silva & Mothes, 2000,  G. splendida Da Silva & Mothes, 2000,  G. pachydermata( Sollas, 1886),  G. thomsonii Schmidt, 1870,  G. apiarium( Schmidt, 1870)and  G. tylastra Boury-Esnault, 1973), having dichotriaenes (  G. spherastrea Lévi, 1964), or having much shorter structural oxeas (  G. gibberosa,  G. papyracea Hechtel, 1965,  G. corticostyliferaHajdu et al.1996,  G. neptuni Sollas, 1886, and  G. vosmaeri Sollas, 1886). Deep water species from the opposite side of the Atlantic differ likewise from our new species:  G. divaricans Topsent, 1928has dichotriaenes,  G. glariosa( Sollas, 1886)has oxeas less than 2 mmin length, and  G. ramosa( Topsent, 1928)and  G. globus Schmidt, 1870lack cortical oxeas. 3328559310 2013-05-27 RMNH L. E. Becking & E. Meesters Bonaire, Sint Eustatius and Saba 156 11.9821 Klein 7 -68.6452 11 412 BDR005 1 holotype 3328559316 1978-08-11 ZMA Barbados 148 For Paynes Bay 11 412 1