Latrunculia (Biannulata) triloba ( Schmidt, 1875 )

Kelly, Michelle, Sim-Smith, Carina, Stone, Robert, Reiswig, Toufiek Samaai Henry & Austin, William, 2016, New taxa and arrangements within the family Latrunculiidae (Demospongiae, Poecilosclerida), Zootaxa 4121 (1), pp. 1-48 : 36

Latrunculia (Biannulata) triloba ( Schmidt, 1875)

( Fig. 14 , 16 AF; Table 9 )

Sceptrella triloba Schmidt, 1875: 119 , Pl. 1, Fig. 17, 18.

Material examined. Holotype — ZMB Por 2667 (2 lots): Bukenfjord on the southwest coast of Norway, 59.333° N, 5.783° E.

Type location. Bukenfjord.

Distribution. North Atlantic Ocean, Northern Norway and Finnmark, southern Norway.

Description. The holotype is a thickly encrusting sponge ( Fig. 14 A–B, D) with compressed tapering aquiferous turrets on the surface, some terminating in oscules, some blunt with microscopic pores. The preserved holotype was originally attached to a Terebratulina brachiopod shell, now composed of six fragments in two lots, probably originally about 48 mm long and wide, about 5–7 mm thick, aquiferous turrets about 2–4 mm long. Location of the areolate pore fields, if present, cannot be determined because of condition of specimens. Texture in life soft, compressible. Colour of preserved holotype golden brown.

Spicules. Megascleres ( Fig. 14 G), anisostyles, slightly centrally thickened, occasionally polytylote, smooth proximally, 370 (350–385) × 11 (10–13) µm.

Microscleres ( Fig. 14 F, H–L), anisodiscorhabds with four distinct whorls, the first is the basal whorl (manubrium indistinguishable or absent), above which is the median, subsidiary and apical whorls, apex absent. Occasionally subsidiary and apical whorls form a barely differentiated tuft of spines, those at the apex are often elongated and irregular, 48 (45–53) × 32 (28–35) µm.

Remarks. In searching for the holotype of Latrunculia tricincta at the Museum für Naturkunde Berlin, Dr Carsten Lüter also found the holotype of Latrunculia triloba ( Schmidt, 1875) , from Bukenfjord on the southwest coast of Norway. The holotype of L. triloba is a wet specimen divided into two lots (preserved in two glass jars carrying the same number); Lot 1 contains 5 pieces, one of which is attached to a Terebratulina brachiopod shell, and Lot 2 contains a single specimen. Unfortunately, the microscope slide mentioned in Hentschel (1929: 870) could not be located. As the gross morphology was not shown in the original description, the illustrations of the microscleres are stylised, and the spicules were not measured, we have taken the opportunity to re-describe the species here, provide new observations ( Fig. 14 , Table 9 ) and to assign the species to one of the Latrunculia subgenera.

Schmidt (1875) stated that the anisostyles are thickest centrally and that the anisodiscorhabds showed greatest kinship with Sceptrella regalis Schmidt, 1870 of Florida, with four whorls of projections that, in end-on profile, form three palmate, indented whorls. Examination of the microscleres of L. triloba ( Fig. 14 H–L) reveals that the normal anisodiscorhabds are not as regular as those of Sceptrella regalis (see Fig. 1 F, left) and the second category of microsclere, the ‘amphityles’ or isoconicorhabds, are absent.

The microscleres are in fact, typical of Latrunculia (Biannulata) species; the anisodiscorhabds have median, subsidiary and apical whorls, an apex, and an undifferentiated basal whorl and manubrium. We transfer the species to subgenus Biannulata ( Table 9 ); this represents the first record of the subgenus outside the Pacific Ocean and further north than South Africa in the Atlantic Ocean.

Figures

FIGURE 1. Comparison of microsclere morphology in family Latrunculiidae (not to scale): A. Anisodiscorhabd form in subgenus Latrunculia (Latrunculia) du Bocage, 1869 (type species L. (L.) bocagei Ridley & Dendy, 1886), showing the six substructures that characterise the anisodiscorhabds, whether differentiated or undifferentiated: m = manubrium, bw = basal whorl, mw = median whorl, sw = subsidiary whorl, aw = apical whorl, a = apex; B. Anisodiscorhabd form in subgenus Latrunculia (Biannulata) Samaai, Gibbons & Kelly, 2006 (type species L. (B.) kaakaariki Alvarez et al., 2002); C. Anisodiscorhabd form in subgenus Latrunculia (Uniannulata) subgen. nov. (type species L. (U.) oparinae Samaai & Krasokhin, 2002); D. Isospinodiscorhabd in genus Cyclacanthia Samaai, Govender & Kelly, 2004 (type species C. bellae (Samaai, Gibbons, Kelly & Davies-Coleman, 2003); E. Isochiadiscorhabd in genus Tsitsikamma Samaai & Kelly, 2002 (type species T. favus Samaai & Kelly, 2002); F. Anisodiscorhabd and amphiclad sceptre in genus Sceptrella Schmidt, 1870 (type species Sceptrella regalis Schmidt, 1870); G. Short anisodiscorhabd and long anisoconicorhabd in genus Latrunclava gen. nov. (type species L. imago gen. et sp. nov.); H. Anisodiscorhabd in genus Bomba gen. nov. (type species B. endeavourensis gen. et sp. nov.). Fig. 1 A, B, D modified and reproduced from Samaai et al. (2006), Samaai et al. (2004) and Samaai et al. (2003), respectively, with permission from Zootaxa (Magnolia Press). Fig. 1 E, F modified with permission from T. Samaai.

FIGURE 14. Morphology, megascleres and microscleres of Latrunculia (Biannulata) triloba (Schmidt, 1875), ZMB Por 2667 (2 lots): A. Portion of holotype in Lot 1 from which spicules were examined (circled), gridlines = 1 mm; B. A second, larger portion of the holotype, showing general surface features and tapering fistules, gridlines = 1 mm; C. Original label included in Lot 1; D. A third section of the holotype showing collapsed, tapering fistules, gridlines = 1 mm; E. Original label included in Lot 2, the asterisk identifies that this is as a type specimen; F. Illustrations of holotype anisodiscorhabds (from Schmidt 1875, Plate 1, Fig. 17, 18); G. slightly sinuous, centrally thickened anisostyle with a smooth head, scale = 100 µm; H, I. Anisodiscorhabd, scale = 50 µm; J. protorhabd, scale = 50 µm; K, L. immature anisodiscorhabd, scale = 50 µm.

FIGURE 16. Comparison of diagnostic anisodiscorhabds in living species of Latrunculia (Latrunculia) du Bocage, 1869, Latrunculia (Biannulata) Samaai, Gibbons & Kelly, 2006, and Latrunculia (Uniannulata) subgen. nov., not to scale: A. L. (L.) triverticillata Alvarez, Bergquist & Battershill, 2002; B. L. (L.) fiordensis Alvarez, Bergquist & Battershill, 2002; C. L. (L.) oxydiscorhabda Alvarez, Bergquist & Battershill, 2002; D. L. (L.) cratera du Bocage, 1869; E. L. (L.) bocagei Ridley & Dendy, 1886; F. L. (L.) basilis Kirkpatrick, 1908; G. L. (L.) brevis Ridley & Dendy, 1886; H. L. (L.) palmata Lévi, 1964; I. L. (L.) ikematsui Tanita, 1968; J. L. (L.) novaecaledoniae Samaai et al., 2006; K. L. (L.) austini Samaai et al., 2006; L. L. (L.) hamanni sp. nov.; M. L. (L.) ciruela Hajdu et al., 2013; N. L. (L.) copihuensis Hajdu et al., 2013; O. L. (L.) verenae Hajdu et al., 2013; P. L. (L.) yepayek Hajdu et al., 2013; Q. L. (B.) kaakaariki Alvarez, Bergquist & Battershill, 2002; R. L. (B.) duckworthi Alvarez, Bergquist & Battershill, 2002; S. L. (B.) procumbens Alvarez, Bergquist & Battershill, 2002; T. L. (B.) wellingtonensis Alvarez, Bergquist & Battershill, 2002; U. L. (B.) kaikoura Alvarez, Bergquist & Battershill, 2002; V. L. (B.) millerae Alvarez, Bergquist & Battershill, 2002; W. L. (B.) spinispiraefera Brøndsted, 1924; X. L. (B.) purpurea Carter, 1881; Y. L. (B.) lunaviridis Samaai, Gibbons, Kelly & Davies-Coleman, 2003; Z. L. (B.) microacanthoxea Samaai, Gibbons, Kelly & Davies-Coleman, 2003; AA. L. (B.) gotzi Samaai, Janson & Kelly, 2012; AB. L. (B.) kerwathi Samaai Janson & Kelly, 2012; AC. L. (B.) algoaensis Samaai Janson & Kelly, 2012; AD. L. (B.) janeirensis Cordonis, Moraes & Muricy, 2012; AE. L. (B.) lincfreesi sp. nov.; AF. L. (B) triloba (Schmidt, 1875); AG. L. (U.) oparinae Samaai & Krasokhin, 2002; AH. L. (U.) velera Lehnert et al., 2006. Fig. 16 A – J, Q – AC reproduced with permission from Zootaxa (Magnolia Press) from Fig. 6 in Samaai et al. (2012), Fig. 16 M – P reproduced with permission from Zootaxa from Fig. 9 in Hajdu et al. (2013), Fig. 16 AD reproduced with permission from Dr Guliherm Muricy, and Fig. 16 AH reproduced with permission from Zootaxa.