Henry M. Reiswig

Sponge reefs in the Queen Charlotte Basin, Canada: controls on distribution, growth and development

Sponge reefs in the Queen Charlotte Basin exist at 165–240 m depth within tidally influenced shelf troughs subject to near bottom current velocities of 25–50 cm s−1 where nutrient supply from coastal runoff is augmented by wind-induced upwelling of nutrient rich water from the adjacent continental slope. Large reef mounds to 21 m in elevation affect tidally driven bottom currents by deflecting water flows through extensive reef complexes that are up to 300 km2 in area. Three hexactinellid species construct reefs by building a siliceous skeletal framework through several frame-building processes. These sponge reefs exist in waters with 90 to 150 µM dissolved oxygen, a temperature range of 5.9 to 7.3°C and salinity of 33.2 to 33.9 ‰. Relatively high nutrient levels occur at the reef sites, including silica, which in bottom waters are typically >40 µM and may be up to 80 µM. A high dissolved silica level is potentially an important control on occurrence of these and other dense siliceous sponge populations. The sponge reefs are mainly confined to seafloor areas where exposed iceberg plough marks are common. Sediment accumulation rates are negligible on the relict, glacial surface where the reefs grow, and trapping of flocculated suspended particulate matter by hexactinosidan or framework skeleton hexactinellid sponges accounts for a large proportion of the reef matrix. Suspended sediment concentration is reduced within the nepheloid layer over reef sites suggesting efficient particle trapping by the sponges. The reef matrix sediments are enriched in organic carbon, nitrogen and carbonate, relative to surrounding and underlying sediments. The sponges baffle and trap suspended sediments from water masses, which in one trough have a residence time of approximately 6 days, ensuring a close association of the sponges with the bottom waters. The location of the reef complexes at the heads of canyons provide a means of regionally funnelling particulate material that sponges can trap to enrich their environment with organic carbon and biogenic silica. Like deepsea coral reefs, the sponge reefs are a remote and poorly known ecosystem that can present logistical challenges and survey costs. Also like deep-sea coral reefs, many of the hexactinosidan sponge reefs have been damaged or destroyed by the groundfish trawl fishery.

A review of the Hexactinellida (Porifera) of Chile, with the first record of Caulophacus Schulze, 1885 (Lyssacinosida: Rossellidae) from the Southeastern Pacific Ocean

All records of the 15 hexactinellid sponge species known to occur off Chile are reviewed, including the first record in the Southeastern Pacific of the genus Caulophacus Schulze, 1885, with the new species Caulophacus chilense sp. n. collected as bycatch in the deep water fisheries of the Patagonian toothfish Dissostichus eleginoides Smitt, 1898 off Caldera (27ºS), Region of Atacama, northern Chile. All Chilean hexactinellid species occur in bathyal to abyssal depths (from 256 up to 4142 m); nine of them are reported for the Sala y Gomez and Nazca Ridges, with one species each in the Juan Fernandez Archipelago and Easter Island. The Chilean hexactinellid fauna is still largely unknown, consisting of only 2.5 % of the known hexactinellid extant species. Further studies and deep water sampling are essential to assess their ecology and distribution, particularly in northern Chile.

Mediterranean hexactinellid sponges, with the description of a new Sympagella species (Porifera, Hexactinellida)

An overview is proposed of the hexactinellid sponge fauna of the Mediterranean Sea, including the description of a new species of Sympagella , S. delauzei sp. nov., collected by ROV during the exploration of deep-sea canyons of the NW Mediterranean and of deep banks and seamounts of the Alboran Sea. The type species of Sympagella , S. nux , is redescribed from specimens from the type locality. An 18S rDNA sequence of the new species was obtained and included in a phylogenetic tree of related hexactinellids. Some modifications to the classification of Rossellidae are proposed according to the new morphological and molecular data obtained during this study: the genera Caulophacus , and Caulophacella are accordingly moved from Rossellinae to Lanuginellinae.

Chapter 4 – Porifera

Publisher Summary Sponges are the simplest of the multicellular phyla. They lack organs, and tissues are their highest level of organization. Specialized cells accomplish many basic biological functions in sponges. Despite their simplicity, however, sponges display a variety of elegant adaptations to freshwater habitats including a strong capacity for osmoregulation, complex life cycles, a capability to feed selectively on a broad range of particulate resources, and, in many species, an intimate association with symbiotic algae. Sponges are common and sometimes abundant inhabitants of a wide variety of freshwater habitats. In some situations, they comprise a major component of the benthic fauna and may play important roles in ecosystem processes in freshwater. This chapter introduces the structure, function, ecology, taxonomy, and diversity of freshwater sponges.

Six new species of glass sponges (Porifera: Hexactinellida) from the north-eastern Pacific Ocean

Six new species of Hexactinellida are described from hard bottom communities of shelf, canyon and seamounts of the west coast of North America: Washington, British Columbia and Gulf of Alaska. They were collected by a variety of methods, trawl, manned submersible, and robot submersible, and hence vary greatly in condition. The six species comprise additions to five different families of the subclass Hexasterophora, Farreidae ( Farrea omniclavata sp. nov. and F. truncata sp. nov.), Euretidae ( Chonelasma oreia sp. nov.), Euplectellidae ( Amphidiscella lecus sp. nov.), Leucopsacidae ( Oopsacas olympicus sp. nov.) and Rossellidae ( Acanthascus malacus sp. nov.). These additions represent an increase of 29% to the known species of Hexactinellida in this area. A completely unique form of defended tabulate stalk is described for A. lecus . The species Chauoplectella spinifera is transferred to Oopsacas .

Rossella podagrosa Kirkpatrick, 1907-A valid species after all.

In this study we provide evidence that the species Rossella podagrosa Kirkpatrick, 1907, commonly considered a synonym of Rossella racovitzae Topsent, 1901, is truly a valid species. We show that it can be clearly distinguished from other species especially when taking into consideration the in situ habitus of the sponge in combination with the spicules. Furthermore we demonstrate the weaknesses in the so far published synonymy concept for the very complicated genus Rossella Carter, 1872. From this we conclude that the best strategy for further analysis of Rossella and establishment of acceptable synonymies will need to be based on detailed examination of the spicules, the holotypes, and in situ habitus. When possible it will be useful to analyze specimens from all Antarctic oceanographic regions.

Taxonomic review of Hadromerida (Porifera, Demospongiae) from British Columbia, Canada, and adjacent waters, with the description of nine new species

The history of sponge collecting and systematics in British Columbia is reviewed over the period 1878 to 1966. Recent additions and changes are provided in an on-line species list: www.mareco/org/kml/projects/NEsponges.asp. Hadromerids are the focus of this paper as eight of 19 species in British Columbia are considered new. An additional new species is described from southern California to clarify the status of Tethya californiana in BC. An update is timely for hadromerids in BC as there is new material and renewed interest, while existing descriptions are often inadequate. We describe new species and provide additions to previous descriptions for sponges of the order Hadromerida (Porifera: Demospongiae) in the cold temperate NE Pacific off British Columbia and adjacent waters. We propose one range extension and one new species in Clionaidae; two range extensions and five new species in Polymastiidae; one range extension, two name changes and two new species in Suberitidae; and one new species in Tethyidae. New species include Pione gibraltarensis n.sp., Polymastia piscesae n. sp., Radiella endeavourensis n. sp., Sphaerotylus raphidophora n. sp., Sphaerotylus verenae n. sp., Weberella perlucida n. sp., Prosuberites saanichensis n. sp., Suberites lambei n. sp., and Tethya vacua n. sp..

New Palaeogene sponges from the Red Bluff Tuff, Chatham Island, New Zealand

Abstract A horizon with well-preserved sponge body fossils occurs in the late Palaeocene–early Eocene Red Bluff Tuff of Chatham Island, located some 850 km east of mainland New Zealand. The body fossils are ‘glass’ and ‘lithistid’ sponges in which most of the original silica has been replaced by calcite during diagenesis, strewn in approximate growth position around the same horizon. We describe two new species, a lyssacinosidan (non-rigid) glass sponge Rossella cylindrica sp. nov. (Class Hexactinellida, Order Lyssacinosida, Family Rossellidae), significant as it provides only the second species in the fossil record of the genus Rossella, and a very large, foliose, tretodictyid (rigid) glass sponge, Anomochone chathamensis sp. nov. (Class Hexactinellida, Order Hexactinosida, Family Tretodictyidae). A large, nodulose lithistid sponge attributed to the Family Corallistidae, but not identifiable to genus, is also described. This material provides a window into the early Tertiary palaeoenvironment of what is now the southern Pacific Ocean. urn:lsid:zoobank.org:act:C8CEF5C8-FD21-4515-9A7C-3C6FCE6F3ACE for Anomochone chathamensis urn:lsid:zoobank.org:act:4C2F6456-2B55-40EF-9B06-26753CE85354 for Rossella cylindrical

New taxa and arrangements within the family Latrunculiidae (Demospongiae, Poecilosclerida)

Extensive new collections of latrunculid sponges from British Columbia, the Aleutian Islands, and the Gulf of Alaska, have extended the distributions of known species Latrunculia oparinae Samaai & Krasokhin, 2002, from the Russian Sea of Okhotsk, L. velera Lehnert et al., 2006, from the Aleutian Islands, and L. austini Samaai et al., 2006, from British Columbia. New material has facilitated detailed re-descriptions of these species and in situ images have improved our understanding of their living morphology and ecology. Several new species of Latrunculia were discovered within these collections: sympatric species Latrunculia hamanni sp. nov. and L. oparinae are described here and differentiated from each other by various field characteristics, and L. lincfreesei sp. nov. is described from the Gulf of Alaska. In terms of their higher systematics, L. austini and L. hamanni sp. nov. are recognisable within the subgenus Latrunculia du Bocage, 1869, and L. lincfreesei sp. nov. in subgenus Biannulata Samaai et al., 2006. A third subgenus, Uniannulata subgen. nov., is proposed for L. oparinae, L. velera and several fossil species in southern New Zealand and Western Australian Eocene fossiliferous sediments. In all of these species the subsidiary whorl, apical whorl, and apex of the anisodiscorhabd are fused. Living species of Uniannulata subgen. nov. are thus far restricted to the North Pacific Ocean. A new genus, Bomba gen. nov., is proposed for a rare latrunculid species, Bomba endeavourensis gen. et sp. nov., discovered in deep waters on British Columbias Endeavour Ridge. Finally, Latrunclava gen. nov. is proposed for species with long, sceptre-like anisoconicorhabds in addition to the typical, smaller anisodiscorhabds; Latrunclava imago gen. et sp. nov. is described from the central Aleutian Islands.

Four new species of Hexactinellida (Porifera) and a name replacement from the NE Pacific

Four new species of Hexactinellida are described from the northwest coast of North America. Two northern ones from bottom longline sablefish traps set on Bowie Seamount off northwest Canada are Pinulasma bowiensis and Rhabdocalyptus trichotis. Two southern forms picked by ROV from the wreck of USS Independence off San Francisco, California are Staurocalyptus pamelaturnerae and Hyalascus farallonensis. A fifth specimen from the southern site is considered conspecific with the junior homonym Farrea aculeata Schulze, and allowed renaming of that species as Farrea schulzei. These additions bring the number of Hexactinellida known from the area (30º-90º N) to 62 species.