Craniella crustocorticata van Soest 2017

Fernandez, Julio C. C., Rodriguez, Pablo R. D., Santos, George G., Pinheiro, Ulisses & Muricy, Guilherme, 2018, Taxonomy of deep-water tetillid sponges (Porifera, Demospongiae, Spirophorina) from Brazil, with description of three new species and new characters, Zootaxa 4429 (1), pp. 53-88 : 69-73

Craniella crustocorticata van Soest 2017

( Figs. 11–12 ; Tabs. 3–4)

Diagnosis. Craniella globular with a strongly conulose surface, a stout basal root, a bladder-like consistency and a

largely tangential surface skeleton (single-layered cortex); three categories of smooth oxeas, two categories of protriaenes (the largest strongly anisoclad), and one category each of anatriaenes and sigmaspires (amended from van Soest 2017).

Synonyms. Craniella crustocorticata van Soest 2017: 109 .

Craniella sp., Muricy et al. 2006: 115.

Material examined. MNRJ 6059 , REVIZEE Programme sta. Central 6-R1#4-2 , Rio de Janeiro State, Southeastern Brazil (21°39’27” S, 40°02’15” W, slope, Campos Basin , circa 106 km NE off Cabo de São Tomé),

box-corer, 700 m depth, coll. N.Oc. Astro-Garoupa team, 13 June 2002. UFPEPOR 2152, UFPEPOR 1785 (fragment of this last material deposited under MNRJ 18547 ), Project PETROBRAS BPOT sta. ARTM-65, Rio Grande do Norte State, Northeastern Brazil (04°33’10.4” S, 36°53’37” W, slope, Potiguar Basin, circa 64 km North off Macau City), 400 m depth, trawling, leg. PETROBRAS, 8 December 2009.

Description. Globular sponge, slightly compressed laterally, with a large and stout root at the base ( Figs. 11A– B ); complete specimen 35 mm high by 27 mm in diameter (main body) and the root 10 cm long. Specimens without root (probably lost during collection), ( Figs. 11C–D ); larger fragment 70 mm high by 40 mm in diameter. Surface, strongly conulose, without oscules or pores apparent; ectosome, a stout crust up to 1 mm thick. Conules larger at the apical and equatorial regions ( Fig. 11E ) and smaller near the root ( Fig. 11F ); up to 1 mm high. Color in vivo pinkish-brown, and cream to beige in ethanol. Consistency hard externally, but soft and very compressible internally.

Skeleton. Skeleton radial, with main bundles of oxeas I and II radiate from the center to the ectosome ending in conules on the surface, protruding up to 350 µm above the surface, up to 300 µm wide and up to 1500 µm of distance each other ( Fig. 11G ). Cortical layer (single-layered cortex) as a continuous mesh of oxeas III, in a tangential way ( Fig. 11H ). Different size categories of oxeas III with different positions in cortical layer; small forms, in a perpendicular way beside the conules beneath the surface; and large forms, predominatly in a tangential way to the surface ( Fig. 11I ). Protriaenes I and II in the main radial bundles of oxeas. Sigmaspires scattered throughout choanosomal region; not present in the cortical layer. Anatriaenes only in the root ( Fig. 11J ).

Spicules. Megascleres ( Tabs. 3–4):

Oxeas I ( Figs. 12A–B ), abundant, relatively stout, straight and smooth. Extremities, equal to slightly different, both with sharp tips: 2812–3845–4740/32–39–52 µm.

Oxeas II ( Figs. 12C–D ), less abundant than oxeas I, straight or slightly curved (more common), and smooth. Extremities equal and with acerate tips: 800–1200–1450/18–26–32 µm.

Oxeas III ( Figs. 12E–F, R ), abundant, exclusively cortical, usually thicker than oxeas I and II, fusiform, slightly curved, and smooth. Extremities, equal and with acerate tips: 375–762–1300/20–44–80 µm.

Protriaenes I ( Figs. 12G–H, N–O ), abundant and relatively slender. Rhabdome, sinuous and thin 2960–3918– 6956/10–15.3–19 µm. Cladome with unequal clads, either with one clad much larger than the other two (more frequent) or with the three clads unequal: 185–243–350 µm length (long clads), 60–102–163 µm length (short clads) by 10–14–18 µm width (both sizes of clads).

Protriaenes II ( Figs. 12I –J, P ), less abundant and smaller than protriaenes I. Rhabdome, slender and flexuous: 975– 1532–2270 /2.5–3.5–6.3 µm. Cladome with three very slender, roughly equal clads: 80–204–320/1–2.2–3 µm.

Anatriaenes ( Figs. 12K–L, O, Q ), abundant and exclusively in the root. Irregular forms, anamonaenes and growth stages (with small cladome) also occur. Rhabdome, larger than that of protriaenes and with variable thickness (thickest in the insertion point of the cladome, thinner in the center, and thickening slightly at the other extremity): 1850–3736–10094/ 12–18–32 µm. Cladome, stout, with clads in an angle of 45º with the rhabdome: 50– 85–190/10–14.5–22 µm.

Microscleres ( Tabs. 3–4):

Sigmaspires ( Fig. 12M ), abundant, ‘c’ shaped and entirely microspined (many large spines): 9.7–13.5–17.7/up to 2 µm.

Ecology and bathymetric distribution. No macrosymbionts were observed. Specimens were collected on muddy bottoms, in deep water (from 400 to 700 m depth).

Distribution. Continental slope of Guyana (van Soest 2017), NE Brazil and SW Brazil (present study; Fig. 1 ).

Remarks. Craniella crustocorticata does not fit strictly in any tetillid genus based on the diagnoses proposed by Carella et al. (2016) due to its single-layered crust of tangential oxeas. However, we agree with its generic assignment in Craniella by van Soest (2017), who argued that other species of Craniella have a paratangential arrangement of oxeas too; e.g., Craniella azorica ( Topsent 1913) . Moreover, the presence of cortex and absence of porocalices is a typical combination of characters of the genus Craniella (van Soest & Rützler 2002) .

Our material is very similar to Craniella crustocorticata from the Guyana shelf (van Soest 2017), in terms of the globular habit, a conulose surface, presence of a radial skeleton with single-layered cortex, and size and shape of spicules ( Tab. 4). On the other hand, the presence of a rooting system is variable. It is present only in our specimens from Campos Basin, collected by box-corer, and is absent in both our specimens from Potiguar Basin, collected by trawling, and in those from the Guyana (van Soest 2017), collected by trawling and van Veen grab. Its absence, therefore, is possibly due to damage during collection.

Craniella crustocorticata was described with one category each of cortical and choanosomal oxeas, although a possible division into two categories of each type has been mentioned by van Soest (2017). We have observed in our material one category of cortical oxeas with a great range of length (375–1250 µm), but two categories of choanosomal oxeas (the larger is often slightly anisoactinal, and the shorter is isoactinal).

Figures

FIGURE 1. Location of the collection sites, from north to south: 1, continental slope in Potiguar Basin, off Macau City; 2, edge of continental shelf off Recife City; 3, slope off Belmonte City; 4, Rodgers Seamount; 5, slope in Espírito Santo Basin; 6, Columbia Seamount; 7, slope in Campos Basin, off Cabo de São Tomé; 8, Almirante Saldanha Seamount. Acronyms are the Brazilian States of: RN, Rio Grande do Norte; PE, Pernambuco; BA, Bahia; ES, Espírito Santo; RJ, Rio de Janeiro. Scale bar: 500 km. Source map from Google Earth.

FIGURE 11. Craniella crustocorticata van Soest 2017: A, specimen from SE Brazil, with a root (MNRJ 6059); B, longitudinal cut showing internally a radial organization (MNRJ 6059); C, external surface of one of the specimens from NE Brazil (root lost during collection), (UFPEPOR 1785); D, a radial organization of another specimen from NE Brazil (root lost during collection), (UFPEPOR 2152); E, conules on the surface (MNRJ 6059); F, detail of the basal region (MNRJ 6059); G, transverse section showing a radial skeleton with choanosomal bundles of oxeas ending in a conule at the surface (MNRJ 6059); H, tangential section of the surface showing cortical oxeas III (MNRJ 6059); I, transverse section showing ectosomal region with oxeas III disposed perpendicular (small forms; black arrows) and tangential to the surface (larger forms; white arrows); J, arrows pointing to cladomes of anatriaenes present in the root. Scale bars: A–B = 10 mm; C–D = 2 mm; E–F = 1 mm; G–I = 500 µm; J = 100µm.

FIGURE 12. Craniella crustocorticata van Soest 2017. A–M, spicules of the specimen from SE Brazil (MNRJ 6059): A, oxeas I; B, detail of tip of oxeas I; C, oxeas II; D, detail of tip of oxeas II; E, cortical oxeas III; F, cortical oxeas III (SEM); G, protriaenes I; H, detail of cladome of protriaene I with anisoclads and variations; I, protriaenes II; J, detail of cladome of protriaenes II with very slender clads; K, anatriaenes; L, detail of cladome of anatriaenes and variations; M, sigmaspires (SEM). N–R, spicules of one of the specimens from NE Brazil (UFPEPOR 1785): N, protriaenes I, arrow point to the large clad crossing the axis of an oxeas III; O, protriaene I and anatriaene; P, protriaene II; Q, anatriaene (SEM), broken; R, oxeas III (SEM). Scale bars: A = 500 µm; B = 40 µm; C = 500 µm; D = 30 µm; E = 500 µm; F = 100 µm; G = 500 µm; H = 100 µm; I = 500 µm; J = 100 µm; K = 500 µm; L = 100 µm; M = 5 µm; N = 100 µm; O = 50 µm; P = 50 µm; Q = 50 µm; R = 200 µm.