Stupenda singularis, Kelly & Cárdenas, 2016

Kelly, Michelle & Cárdenas, Paco, 2016, An unprecedented new genus and family of Tetractinellida (Porifera, Demospongiae) from New Zealand’s Colville Ridge, with a new type of mitochondrial group I intron, Zoological Journal of the Linnean Society (Zool. J. Linn. Soc.) 177 (2), pp. 335-352 : 344-346

STUPENDA SINGULARIS SP. NOV.

( FIGS 1 , 5 , 6 , TABLE 3)

Holotype

NIWA 86177 : TAN1213/19, 18.x.2012, collected by epibenthic sled from RV Tangaroa, preserved in 70%

ethanol. UPSZTY 159997, piece preserved in 70% ethanol and spicule preparation.

Type location

30°10′37.2″S, 179°44′13.2″W, 387–422 m, Colville Volcano , Colville Ridge, New Zealand Exclusive Economic Zone .

Distribution

Known only from Colville Ridge.

Description

Spherical sponge attached to dead coral, 20 mm high, 16 mm diameter ( Fig. 5A ), with a distinct 4-mmthick semi-translucent cortex ( Fig. 5B ). The surface is rough and armoured with projecting orthotriaene megascleres. Texture in life is tough, incompressible externally, cortex thick and rigid, choanosome slightly fleshy. Colour in life dull yellow to cream.

NIWA, National Institute of Water & Atmospheric Research.

Skeleton

Oxeas radiate strictly from a centrum in the middle of the choanosome, forming tracts that extend through the thick cortex and beyond. Orthotriaenes form bouquets in the cortex ( Fig. 5C, D ) and extend well beyond the surface of the sponge ( Fig. 5B, D ), the clubbed cladomes of the triaenes forming a closely packed armour.

Spicules

Megascleres ( Table 3): Oxeas ( Fig. 6A ), straight, thickest in middle, attenuates to a fine to slightly rounded point, 4193 (3250–4850) × 69 (40–85) μm. Orthotriaenes I ( Fig. 6B–H ) with perfectly straight, conical rhabdome and rounded distal end. Cladome narrow, clads clubbed, typically spherical ( Fig. 6C ) to reduced ( Fig. 6D ), often modified to diaenes ( Fig. 6E ), rarely to monaenes ( Fig. 6F ). Cladome and upper rhabdome acanthose with regularly spaced low mounds. Occasionally entirely smooth: total length (cladome + rhabdome) 2773 (2075– 3075) μm, maximum rhabdome width 158 (140– 180) μm, total cladome width 195 (140–240) μm, clad length from axial inception 107 (80–140) μm. Orthotriaenes II with a relatively short, straight rhabdome and pointed distal end. Cladome normal with short robust slightly curved clads, one or two often clubbed, often modified to diaenes, frequently smooth to faintly acanthose, or acanthose with regularly spaced low mounds: total length (cladome + rhabdome) 2067 (1325–2500) μm, N = 8, maximum rhabdome width 96 (75–110) μm, total cladome width 187 (100–300) μm, clad length from axial inception 104 (50–150) μm.

Microscleres ( Table 3): Sigmaspires ( Fig. 6I ), lightly and irregularly spined along the axis, more heavily spined at the ends, spines arranged in a clawed arrangement or extending laterally, contort, length 5 (4–6) μm.

Substrate and ecology

Attached to a piece of coral rubble. The habitat was predominantly coral rubble and pumice, which supported high numbers and diversity of hard and soft corals, plexaurid gorgonians, and sea anemones ( Wysoczanski et al., 2012).

Etymology

Named after the unique characteristics of the species and the remarkable nature of the spicule complement ( singularis , unique, extraordinary; Latin).

Figures

Figure 1. Study area showing the collection locality for Stupenda singularis gen. et sp. nov. (●), Colville Ridge volcano, Colville Ridge, New Zealand Exclusive Economic Zone.

Figure 5. Morphology and skeletal architecture of Stupenda singularis gen. et sp. nov., holotype NIWA 86177, Colville Ridge, Kermadec Volcanic Arc, 387–422 m: A, preserved specimen, scale bar = 10 mm; B, preserved specimen showing thick cortex and strictly radiating skeleton, emanating from a centrum, scale bar = 10 mm; C, D, histological thick section showing strictly radiating megascleres in cortex, scale bars = 200 μm.

Figure 6. Megascleres and microscleres of Stupenda singularis gen. et sp. nov., holotype NIWA 86177, Colville Ridge, Kermadec Volcanic Arc, 387–422 m: A, oxea, one end showing strong attenuation, scale bar = 1000 μm; B, orthotriaene I megascleres with clubbed clads, scale bar = 1000 μm; C, orthotriaene I megascleres with clubbed bulbous clads, scanning electron microscopy (left), light microscopy (LM) (right), scale bar = 200 μm; D, orthotriaene I megasclere with reduced irregular clads, scale bar = 200 μm; E, orthotriaene I megascleres with diaene modifications, scale bar = 200 μm; F, orthotriaene I megasclere with monaene modification, LM, scale bar = 200 μm; G, orthotriaene II megasclere with normal clads, scale bar = 200 μm; H, orthotriaene II megasclere with irregular reduced clads, entirely smooth, scale bar = 200 μm; I, sigmaspires, scale bar = 5 μm.