Mycale (Naviculina) cleistochela, Vacelet & Vasseur, 1971

Van, Rob W. M., Aryasari, Ratih & De, Nicole J., 2021, Mycale species of the tropical Indo-West Pacific (Porifera, Demospongiae, Poecilosclerida), Zootaxa 4912 (1), pp. 1-212 : 147-151

Mycale (Naviculina) cleistochela ( Vacelet & Vasseur, 1971

Figs 93 a–c, 94a–j, 95a–g, 96

Mycale cleistochela Vacelet & Vasseur, 1971: 87 , fig. 36.

Mycale cleistochela var. flagellifera Vacelet & Vasseur, 1971: 87 , fig. 37

Mycale (Aegogropila) peculiaris Pulitzer-Finali, 1996: 116 , fig. 14.

Mycale (Naviculina) cleistochela ; Hajdu 1999: 228.

Mycale (Naviculina) peculiaris ; Hajdu 1998: 228.

Material examined. MSNG 48704 , slide of holotype of Mycale peculiaris Pulitzer-Finali, 1996 , MSNG 48704 , Papua New Guinea, Laing Island , 4.15°S 144.8667°E, depth 15 m , SCUBA, coll. G. Pulitzer-Finali, field nr. P54, 12 August 1986 .

ZMA Por. 08512, Indonesia, Nusa Tenggara, N coast of Sumbawa, Bay of Sanggar , 8.32°S 118.24°E, depth 5–7 m , SCUBA, coll. R. W.M. van Soest, Indonesian-Dutch Snellius II Expedition stat. 114, field nr. 114/ III/15 , 21 September 1984 (yellow) ; ZMA Por. 08896, Indonesia, Sulawesi, SE Sulawesi, NE Take Bone Rate, S of Tarupa Kecil, 6.5°S 121.1333, depth 10–15 m , SCUBA, coll R. W.M. van Soest, Indonesian-Dutch Snellius II Expedition, stat. 139, field nr 139/ IV/15 , 25 September 1984 (orange) ; ZMA Por. 08897, Indonesia, Sulawesi, SE Sulawesi, NE Take Bone Rate, S of Tarupa Kecil, 6.5°S 121.1333, depth 10–15 m , SCUBA, coll R. W.M. van Soest, Indonesian-Dutch Snellius II Expedition, stat. 139, field nr 139/ IV/15 , 25 September 1984 (orange) ; ZMA Por. 08917a, Indonesia, Sulawesi, SE Sulawesi, NE Take Bone Rate, S of Tarupa Kecil, 6.5°S 121.1333, depth 10–15 m , SCUBA, coll R. W.M. van Soest, Indonesian-Dutch Snellius II Expedition, stat. 139, field nr 139/ IV/36 , 25 September 1984 ; ZMA Por. 13069, Indonesia, SW Sulawesi, Samalona , 4.8747°S 119.3419°E , SCUBA, coll. N.J. de Voogd, field nr. SA / NV/280497/02, 28 April 1997 (bright orange) ; ZMA Por. 15126, Indonesia, SW Sulawesi, Samalona , SCUBA, coll. B.W. Hoeksema, field nr. 220608, 22 June 1997 (orange) ; ZMA Por. 15185, Indonesia, SW Sulawesi, Samalona E , SCUBA, coll. B.W. Hoeksema, field nr. 060502, 6 May 1997 (bright orange) ; ZMA Por. 15246, South Africa, Port Elizabeth, Cove Rock , 33.1°S 27.8333°E, depth 0–2 m , snorkeling, coll. A. van Schie, field nr. UPES–96–158, 19 March 1996; ZMA Por. 17503, Indonesia, SW Sulawesi, Spermonde Archipelago , SCUBA, coll. D. Erpenbeck & N.J. de Voogd, field nr. 2–21, 12 May 2001 ; RMNH Por. 1904, Indonesia, Bali, Tulamben area , bay S of Emeral Hotel, 8.2847°S 115.603°E, depth 4 m , SCUBA, coll. N.J. de Voogd, Bali-Lombok Strait Expedition 2001, field nr. BAL.23/140401/190, 5 April 2001 (orange) ; RMNH Por. 4260, Indonesia, East Kalimantan, Berau region , W Panjang, 2.3312°N 118.1791°E, depth 10 m , SCUBA, coll. N.J. de Voogd, field nr. BER.106/140808/059, 14 August 2008 .

Description ( Figs 93 a–c). Massively lobate orange sponges ( Fig. 93a ) with characteristic reticulated surface. The lobes are crowned by large oscules, up to 1 cm in diameter, with membranous transparent upper parts. Size may be considerable, often 12 cm or more in lateral expansion and 3–5 cm high, but incipient specimens may be thin crusts of only a few cm in size. Below the surface membrane many rounded lacunae are visible, producing a coarsely punctate aspect. In preservation, colors become light beige or reddish brown ( Figs 93 b–c), and the surface membrane is easily detachable. Consistency softly compressible, easily damaged.

Skeleton ( Figs 94 a–b). The choanosome has large lacunae, but between these the skeleton has very thick spicule tracts up to 1 mm in diameter with numerous megascleres in cross section. Towards the surface these subdivide into thinner tracts which are 60–100 µm in diameter, carrying the surface skeleton. This tangential ectosomal skeleton ( Fig. 94a ) is of the aegogropila-type, with intercrossing spicule tracts of about 50 µm diameter (6–10 spicules in cross section) forming triangular meshes. Rosettes of anisochelae ( Figs 94 a–b) are found in the ectosomal region, concentrated on the intersections of the ectosomal tracts.

Spicules ( Figs 94 c–j, 95a–g). Mycalostyles, normal shaped anisochelae, two categories of naviculichelae, two categories of sigmas one of which may be flagellated, toxas.

Mycalostyles ( Figs 94c,c 1 , 95a,a 1 ), comparatively long, slim, or thicker, with barely developed subapical constriction, sharply pointed or mucronate ending, size possibly regionally determined, 360– 497.1 –588 x 8– 10.6 – 15 µm ( Vacelet & Vasseur 1971: 480–640 x 5–18 µm).

Anisochelae I ( Figs 94d , 95b ), normal-shaped, elongate, with free part of the shaft 30–40% of spicule length, with upper and lower alae well-developed, upper median alae comparatively narrow, 42– 50.9 – 63 µm (V&V: 42–50 µm).

Anisochelae II ( Figs 94e , 95c ), naviculichela-shape, tending to be rectangular in shape, having distinctly different asymmetrical sides ( Figs 94e ), one side with alae smoothly merging with central plate, the other provided with sharp ridges, upper rim of central plate provided with one or more spines, size 23– 29.1 – 35 µm (V&V: 20–30 µm).

Anisochelae III ( Figs 94f , 95d ), naviculichela-shape, similar to anisochelae II, but with oval outline, 12– 17.4 – 22 µm (V&V: 12–18 µm).

Sigmas Ia ( Figs 94h , 95e ), normal-shaped, about 1.5 µm in diameter, almost symmetrical, with incurved endings, 37– 54.7 – 66 µm (V&V: 70–90 µm); always present.

Flagellated sigmas (sigmas Ib) ( Fig. 94g ), asymmetrical, at least as wide as high but usually wider, with sharply incurved endings, presence variable, occasionally entirely absent or shape merged with normal-shaped sigmas I, width x height 39– 73.3 –96 x 34– 54.8 – 78 µm (V& V: 65–75 µm).

Sigmas II ( Figs 94i , 95f ), thin, symmetrical, with incurved endings, 11– 14.3 – 32 µm (V&V: 15–45 µm).

Toxas ( Figs 94j , 95g ), with wide curve and upturned endings, may occur in small bundles but usually single, 9– 21.4 –33 (V&V: 15–20 and 30–60 µm).

Distribution and ecology ( Fig. 96 ). Indonesia, South Africa, Madagascar, Papua New Guinea. In shallow water down to 15 m depth, frequent on reefs.

Remarks. The occurrence of specimens with few or even absent flagellated sigmas in combination with sigmas I of about the same size differing from flagellated sigmas only in the amount of curvature has convinced us that the variety flagellifera is not specifically different from M. (N.) cleistochela . Since there is no clear geographic separation between specimens with many (e.g. ZMA Por. 15126) and specimens with few flagellosigmas (e.g. ZMA Por. 08897), the likelihood of separate subspecies is judged to be low. Thus, both varieties are here merged. One detail, provided in the description of Vacelet & Vasseur (1971) did not match our specimens, i.e the toxas reported in Mycale cleistochela by them were up to 60 µm, twice the size of the toxas found by us. Still, toxas are notably variable in length in most toxa-bearing Mycale species, so not much value can be attached to the length difference.

Below we describe a set of specimens as a new species from Rodrigues Island in the Mascarenes, which possess flagellosigmas and naviculichelae, but lack proper sigmas and toxas.

Pulitzer-Finali’s Mycale peculiaris was re-examined and flagellated sigmas were found in his material. It conforms closely in spicule shapes and sizes with the present species. Remarkably, Lerner & Hajdu (2002: p. 112), did not accept M. peculiaris as a member of subgenus Mycale (Naviculina) , as it would have a separate type of anisochelae proposed to be named ‘peculichelae’. We do not agree after examination of a slide of the holotype. M. peculiaris has the naviculichelae in the shape and the size of M. (N.) cleistochela and is a clear junior synonym.

Figures

FIGURE 1. A. Numbers of available specimens for the present study from the collections of the Naturalis Biodiversity Center distributed over Indo-West Pacific Marine Ecoregions (MEOWS, cf. Spalding et al. 2007). B. Ditto for type specimens and additional specimens from other institutions consulted for this study.

FIGURE 93. Mycale (Naviculina) cleistochela Vacelet & Vasseur, 1971, habitus, a, RMNH Por. 1904 in situ, from Bali, Indonesia (photo N.J. de Voogd), b, ditto preserved, c, ZMA Por. 15126 preserved, from SW Sulawesi, Indonesia (scale bar = 1 cm).

FIGURE 94. Mycale (Naviculina) cleistochela Vacelet & Vasseur, 1971, RMNH Por. 1904 from Bali, Indonesia, skeleton and spicules, a–b, light microscopic images of the skeleton, a, aegogropila-type ectosomal skeleton, b, detail of a, showing a.o. flagellated sigmas, c–j, SEM images of spicules, c, mycalostyle, c1, details of mycalostyle, d, anisochela I, e, anisochelae II showing slightly different sides, f, anisochela III (anisochela II and III at same scale), g, flagellated sigma Ib, h, normal sigma Ia, i, sigma II, j, toxas.

FIGURE 95. Mycale (Naviculina) cleistochela Vacelet & Vasseur, 1971, ZMA Por. 08917a, from SW Sulawesi, Indonesia, SEM images of spicules (flagellated sigmas lacking), a, mycalostyle, a1, details of mycalostyle, b, anisochela I, c, anisochela II, d, anisochela III (all anisochelae at same scale), e, normal sigmas Ia (sigmas Ib absent), f, sigma II, g, toxas.

FIGURE 96. Mycale (Naviculina) cleistochela Vacelet & Vasseur, 1971, approximate distribution of specimens studied (light blue squares) and literature records (pale blue dots). Squares and dots may represent several close collecting localities.