Latrunculia (Biannulata) lincfreesei Kelly, Reiswig & Samaai, sp. nov.
Creators: name: Kelly, Michelle
name: Sim-Smith, Carina
name: Stone, Robert
name: Reiswig, Toufiek Samaai Henry
name: Austin, William
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Porifera
Demospongiae
Poecilosclerida
Latrunculiidae
Latrunculia
Latrunculia lincfreesei

description: Latrunculia (Biannulata) lincfreesei Kelly, Reiswig & Samaai sp. nov.
(Fig. 2 B, 7, 16AE; Tables 3, 8, 9)
Material examined. Holotype — RBCM 015-00486-001: Shumagin Bank, 37.8 km SSW of Simeonof Island, Shumagin Islands, Gulf of Alaska, 54.563° N, 159.042° W, 139 m, 15 Jun 2013, NOAA Fisheries, FV Ocean Explorer, Station-haul 72, Cruise 201301, collected by N. Laman. Paratype— RBCM 015-00486-002: same locality data.
Type location. Shumagin Bank, Gulf of Alaska.
Distribution. Shumagin Bank, Gulf of Alaska.
Description. Spherical to elongate, thickly encrusting sponge, extremely wrinkled, folded, cavernous, contracted in life and when preserved, holotype about 4 cm high and wide (Fig. 7 A), by 2 cm thick, paratype about 6 cm long, 2 cm wide, 2 cm thick (Fig. 7 B). Surface covered in thin, almost strappy turrets about 1 cm high, some tapering to a point, some appear rounded on the ends, location of the areolate pore fields cannot be determined because of condition of specimens. Texture in life soft, compressible. Colour in life is bright orange-brown, turrets slightly lighter in colour. Attached to large, smooth pebbles (Fig. 7 A, B).
Skeleton. A layer of vertically positioned anisodiscorhabds, several spicules deep, forms a palisade in the ectosome, below which is a layer of megascleres, 300–1000 µm thick, that are paratangential to the ectosome, criss-crossed in arrangement, and vertical near the pore fields. The choanosomal architecture is fibrous with huge tracts, 250–500 µm wide, forming a wide-meshed, irregular reticulation. Abundant anisodiscorhabds are scattered between the megascleres in the choanosome.
Spicules. Megascleres (Fig. 7 D, E; Table 3), anisostyles, fusiform, slightly sinuous, head acanthose, 541 (480– 590) × 13 (10–15) µm.
Microscleres (Fig. 7 F–J; Table 3), anisodiscorhabds, manubrium absent in over 60% of microscleres (Fig. 7 F). In about 40% of anisodiscorhabds in the holotype and 10% of anisodiscorhabds in the paratype (Fig. 7 G, J) a single, double or three-pronged microspined spine projects from the base of the shaft. The basal whorl consists of several thick sharp sculpted spines, which are ornamented with single spines and rows of tiny teeth, spines strongly curved horizontally then obliquely away from the shaft. The median and subsidiary whorls are also composed of serrated sculpted spines, approximately equal in diameter. The apical whorl consists of numerous thick, sharp, doublet spines that curve gently away from the shaft. There is no visible apex in any spicule. Anisodiscorhabds without manubrium, 63 (58–70) × 35 (30–38) µm, anisodiscorhabds with manubrium, slightly longer at 68 (63–73) × 35 (30–43) µm.
Substrate, depth range and ecology. Collected by trawl from a relatively flat seafloor with pebbles, cobbles and sand, in an area experiencing relatively high currents. Grows on bedrock, pebbles, sand and cobbles, in moderate current at a depth of 139 m.
Etymology. Named for J. Lincoln Freese, retired fisheries research biologist from Auke Bay Laboratories (NOAA Fisheries), who pioneered the use of deep-sea submersibles to study seafloor and sponge ecology in the Gulf of Alaska.
Remarks. The anisodiscorhabds of L. lincfreesei sp. nov. are very similar in appearance to those of southern hemisphere L. (Biannulata) species (Fig. 6 Q–AF), with only two whorls of spines between the terminal substructures, the median and subsidiary whorls. In the majority of microscleres in the type specimen, the basal whorl forms a cuff of double spines slanting away from the shaft of the spicule; the manubrium is not apparent as an independent substructure. Similarly, the apical whorl forms a crown of doublet spines that slant away from the shaft and an apex tuft or spine is not apparent (Fig. 7 F, H–I).
In about 40% of anisodiscorhabds in the holotype, and about 10% in the paratype, and in some protorhabds, there is a large, frequently divided, acanthose manubrium projecting from the base of the spicule (Fig. 7 G, J). Although the presence of a distinctive manubrium in some spicules might suggest affinity of L. lincfreesei sp. nov. with the subgenus Latrunculia, the most pragmatic decision is to recognise the dominant form of the microscleres, those without a manubrium, thus classifying the species with the L. (Biannulata) group. In terms of the overall structure and micro-ornamentation, the anisodiscorhabds of L. lincfreesei sp. nov. are very similar to those of L. (B.) triloba Schmidt, 1875 (Fig. 14, 16 A–F), from the southwest coast of Norway, but the spicules of the latter are much smaller (anisostyles, 370 (350–385) × 11 (10–13) µm; anisodiscorhabds, 48 (45–53) × 32 (28–35) µm). Latrunculia (B.) lincfreesei sp. nov. is distinguishable from other North Pacific Latrunculia species in the form of the sponge, being highly cavernous with strappy surface turrets, and in the larger size of the anisostyles and anisodiscorhabds, which are also highly characteristic in morphology and ornamentation.
description: Published as part of Kelly, Michelle, Sim-Smith, Carina, Stone, Robert, Reiswig, Toufiek Samaai Henry & Austin, William, 2016, New taxa and arrangements within the family Latrunculiidae (Demospongiae, Poecilosclerida), pp. 1-48 in Zootaxa 4121 (1) on pages 14-16, DOI: 10.11646/zootaxa.4121.1.1, http://zenodo.org/record/265513