Lamellomorpha strongylata Bergquist, 1968

Figs 1–2, 6; Tables 1–2

Lamellomorpha strongylata Bergquist, 1968 (in part): 31–32, pls 4a, 11e–f, fig. 10.

Lamellomorpha strongylata — Cryer et al. 2000: 21, appendix 8a–b. — Hooper & Maldonado 2002: 165 –167, fig. 1. — Hickford 2007: 40. — Kelly et al. 2009: 42. — NABIS 2017: 1 –4.

‘ Lamellomorpha n. sp. K & W’ in Cryer et al. 2000: 42 (NIWA 51169 leg.).

Type material

Holotype NEW ZEALAND • Northeast of Three Kings Islands, NZOI Station B93; 33.983° S, 172.350° E; depth 54–109 m; 22 Oct. 1958; NIWA 356 (NZOI H–33) leg.; beam trawl; UPSZTY 178600 (a piece of the holotype preserved in 70% ethanol, as well as a spicule preparation), NIWA.

Other material examined

NEW ZEALAND – Northeast of Three Kings Islands, NIWA Station Z9678 (KAH9901/27); 34.360° S, 172.712° E; depth 48 m; 26 Jan. 1999; NIWA 51169 and 51172 leg.; UPSZMC 178601 (fragment of NIWA 51172 leg. preserved in 70% ethanol), NIWA • Northeast of Three Kings Islands, NIWA Station Z9686 (KAH9901/43); 34.361° S, 172.686° E; depth 48 m; 27 Jan. 1999; NIWA 51267 leg.; UPSZMC 178603 (fragment preserved in 70% ethanol), NIWA • Northeast of Three Kings Islands, NIWA Station Z9699 (KAH9901/67); 34.360° S, 172.673° E; depth 41 m; 28 Jan. 1999; NIWA 51438 leg.; NIWA • Northeast of Three Kings Islands, NIWA Station Z9710 (KAH9901/85); 34.353° S, 172.765° E; depth 54 m; 28 Jan. 1999; NIWA 51582 leg.; dredge; NIWA • Three Kings Islands, 2.5 nm east of Great Island, NIWA Station Z15944; 34.170° S, 172.210° E; depth 200 m; 16 Apr. 1999; CRRF, NIWA 93474 leg.; dredge; NIWA • Spirits Bay, Northland, NIWA Station KAH0606/D3; 34.36° S, 172.847° E; 15 May 2005; NIWA 52375 leg.; dredge; NIWA. • Middlesex Bank, Three Kings Rise, NIWA Station TAN1105/43; 33.988° S, 171.751° E; depth 170–174 m; 28 Mar. 2011; NIWA 73243, 73253 leg.; beam trawl; NIWA • Western Continental Slope, Northland, NZOI Station J954 (I808); 34.633° S, 172.225° E; depth 204– 192 m; 18 Jun. 1981; collected by rock dredge; specimen now lost, donated by Dame P. R. Bergquist to Dr P. Karuso, Macquarie University, Sydney .

Description

The holotype was described by Bergquist (1968) as a “massive, thick, sometimes folded and incurved lamellate sponge”, 130 mm high, 102 mm wide, and 18–22 mm thick, supported by a stout stalk 30 mm in diameter. The surface was described as smooth where the dermal membrane was intact, otherwise ragged due to projecting clumps of oxeas and strongyles. Oscules, 1–2.6 mm in diameter, were found on the convex surface of the lamella and lie flush with the surface (Bergquist 1968). Examination of the numerous preserved specimens in NIC reveal occasional membranous oscules, but it is difficult to tell whether they are restricted to one side of the sponge. However, in the holotype, pores were observed on the opposite side to the oscules, in cribriporal areas, separated by small ridges, or with no boundaries, making a continuous pore surface; each pore is 40–80 µm in diameter. The texture was described as, “firm but compressible, crisp, easily broken”. The colour in life was described as “bright green” and the colour in spirit, “blue green or yellowish green” (Bergquist 1968). The most recent collection was by the Coral Reef Research Foundation in 1999 (NIWA 93474 leg.; Fig. 2A), who described a “dark, royal blue (not navy blue), (palmate) fan sponge with pointed tips, 20 cm high and about 1 cm thick, that tears easily, and which has a fleshy surface”.

Skeleton

The description by Bergquist (1968) of the choanosome as “lax and confused with slight traces of radiate construction discernible”, is accurate, but in NIWA 93474 leg. the contort strongyles strongly radiate through the plane of the fan. Bergquist described a “subectosomal region”, in which there were tracts of megascleres, variable in thickness, that curved outward and intersect with the surface at an acute angle; in NIWA 93474 leg. these are predominantly oxeas (Fig. 6A). The ectosome is densely packed with microstrongyles and streptasters, which also occur throughout the sponge, but in much less abundance.

Spicules

MEGASCLERES (Table 1; Fig. 2D)

Bergquist (1968) considered the megascleres of L. strongylata (Bergquist 1968: 31, 32 (table of spicule dimensions)) to be “strongyles, oxeas and strongyloxeas”, all of similar range in length and width, varying only in relative frequency in the two specimens (presumably the Three Kings holotype and the NZOI Station B 176 specimen from Campbell Plateau), with oxeas being dominant in the latter. Re-examination of the holotype megascleres, and those of more recent collections, indicate that there are probably two forms of megascleres: 1) straight to slightly curved oxeas that are common in the subectosomal tracts, ranging from about 1500–1750 µm long and up to 25 µm thick; and 2) massive sinuous or contort oxeas that are usually very thick and frequently modified with one or both ends rounded as in strongyloxeas, rarely as in true strongyles, ranging from about 1600–2375 µm long and up to 40 µm thick. However, it is difficult to distinguish the various megascleres in some specimens, and in some the spicules are much less contort.

MICROSCLERES (Table 2; Fig. 2 C–F)

Microstrongyles are “squat, evenly rounded spicules, slightly roughened and occasionally centrotylote” (Bergquist 1968: 31, 32 (table of spicule dimensions)) and range from about 21–34 µm long (Table 2). Bergquist described the streptaster microscleres of L. strongylata (Bergquist 1968: 31, 32 (table of spicule dimensions)) as “plesiasters, small spicules with 3–12 smooth, sharply pointed rays”. A reexamination of the holotype (Fig. 2 E–F) using scanning electron microscopy has revealed that the streptaster microscleres are metasters and occasionally amphiasters with relatively long microspined rays, all in one size category, following the definition of Sollas (1888), and as used in Cárdenas & Rapp (2012). We describe these spicules as metaster- to amphiaster-like streptasters with heavily spined, relatively long rays in one size category, ranging in length from about 7–15 µm long (Table 2).

Distribution

Northeast of New Zealand.

Substrate, depth range and ecology

Attached to rocky reefs and sediment and rubble-covered rocky platforms, depth 41– 200 m.

DNA barcodes

COI. NIWA 51172 leg. (minibarcode, MK033624) and NIWA 51267 leg. (MK033623): no bp differences. 28S (C1-C2). NIWA 51172 leg. (MK 033143) and NIWA 51267 leg. (MK 033142): no bp differences. We failed to get sequences from the holotype.

Remarks

Lamellomorpha strongylata was originally described in considerable detail by Bergquist (1968), and the holotype was redescribed without re-examination more recently by Hooper & Maldonado (2002). No further material was examined. Here, for the first time, we illustrate the sponge as it appears upon collection, showing the beautiful royal blue colouration (Fig. 2A), and illustrate the detail and ornamentation of the microscleres (Fig. 2 C–F) using scanning electron microscopy. There is little to add to the original description, consequently the description and skeletal details are provided in comparative prose. Lamellomorpha strongylata is restricted to the northernmost tip of New Zealand and beyond to the Three Kings Rise, and is easily recognised in the field by the palmate, tree-like shape and the deep blue to green colouration.