Background A numer of Haliclona species (Demospongiae, Haplosclerida) in the Austin and McDaniel collections at the Royal British Columbia Museum (RBCM) are identified only to genus or genus and species. The collections are representative of over 40 years of sampling principally by the late Dr. William C. Austin and one of us (Neil McDaniel) through SCUBA diving on the west coast of British Columbia and specimens provided by others to Dr. Austin. We have selected representative Haliclona species in the collections for detailed examination and placement in subgenera and species (where species were not identified). Haliclona is recognized to have several subgenera, thus identification of specimens to genus and species is incomplete. Our study updates this status for the species examined.Methods Methods of collection included intertidal scrapings or removal of non-encrusting specimens usually accompanied by in-situ photos, similar methods at SCUBA diving depths (subtidal to 35 m) and from other dredging, trawling and biological sampling activities.Results We describe eleven new Haliclona (Demospongeae Haplosclerida Chalinadae) species and a range extension for Haliclona ( Flagellia ) edaphus de [Laubenfels, 1930][1] for shallow waters of Southwestern British Columbia, Canada. New species include Haliclona ( Gellius ) hartmani n. sp. , Haliclona ( Gellius ) shishalhensis n. sp. , Haliclona ( Reniera ) gesteta n. sp. , Haliclona ( Rhizoniera ) aborescens n. sp. , Haliclona ( Rhizoniera ) blanca n. sp. , Haliclona ( Rhizoniera ) boothensis n. sp., Haliclona ( Rhizoniera ) filix n. sp. , Haliclona ( Rhizoniera ) kunechina n.sp., Haliclona ( Rhizoniera ) meandrina n. sp., Haliclona ( Rhizoniera ) penelakuta n. sp. , and Haliclona ( Rhizoniera ) vulcana n. sp. We also redescribe Haliclona mollis ([Lambe, 1893][2] [1894]) and propose placing it in the subgenus Haliclona . Except for Lambe’s syntype slides of Haliclona mollis which are deposited at the Canadian Museum of Nature, Ottawa, Canada, all holotypes and voucher specimens of species described are deposited at RBCM.### Competing Interest StatementThe authors have declared no competing interest. [1]: #ref-27 [2]: #ref-26

Collections of encrusting sponges from the shallow subtidal zone of three southern fjords in British Columbia, Canada, and adjacent waters provided the material for the description of 14 new species. Species represent 5 orders, 8 families and 11 genera providing a cross section of British Columbia shallow water fjord Demospongiae. New species include Eurypon reiswigi n. sp., E. scruposus n. sp., E. microtuberculatum n. sp., Hymeraphia pacifica n. sp., Hamigera bakusi n. sp., Hymedesmia (Hymedesmia) anvilensis n. sp., Hymetrochota austini n. sp., Discorhabdella atypica n. sp., Antho (Acarnia) flavoaurantiaca n. sp., Clathria (Microciona) aquaradiata n. sp., Hymeniacidon globularis n. sp., Oceanapia polytuba n. sp., O. flava n. sp., and Spongionella tenuis n. sp. Species range from uncommon to common both within and outside fjord environments. Range extensions of genera include: Eurypon, Northeast Pacific range extension from Mexico to BC; Hymeraphia, range extension to the Northeast Pacific, Hamigera, range extension to the Northeast Pacific, Hymetrochota, range extension to the Northeast Pacific and depth extension to shallow water, and Oceanapia, Northeast Pacific range extension from the Gulf of California to central BC.

Mycale (Mycale) loveni (Fristedt, 1887) is a very large structure-forming sponge that has previously been reported in the North Pacific, North Atlantic, and Arctic oceans. Through morphological and molecular examination, North Atlantic and Eastern Canadian Arctic specimens are now described as a new species, Mycale (Mycale) lorea sp. nov. The two species have similar external morphology; however, the spicules that make up their skeletons differ in size and shape, and the species are also separated phylogenetically by multiple genetic markers.

The non-native European sponge Hymeniacidon perlevis (Montagu, 1814) (= H. sinapium de Laubenfels, 1930) is established and abundant in the head of Ladysmith Harbour, southern British Columbia, Canada, where it was first detected in 2008. In the North Pacific Ocean, it was previously known with certainty from California, Korea and Japan. It may have been introduced to Ladysmith from Asia between the 1950s and 1970s with importations of commercial oysters (Crassostrea gigas (Thunberg, 1793)). Ladysmith Harbour supports some of the warmest marine waters of Western Canada; should water temperatures increase in adjacent regions, H. perlevis may expand its range and be an important indicator of climate change.

Glass sponges (Porifera, Hexactinellida) form globally unique reefs that support deep-sea biodiversity in the Canadian northeast Pacific. In February 2017, the largest known reefs were protected within the Hecate Strait and Queen Charlotte Sound Glass Sponge Reefs Marine Protected Area (HSQCS-MPA). Many studies that have established baseline biodiversity data for the MPA have focused on describing the crustaceans and fish living in the reefs, but the relationship between glass sponges and sponge epibionts has often been overlooked. We studied one of the more conspicuous sponge epibionts of the genus Desmacella Schmidt, 1870 , a demosponge that encrusts the surface of reef-forming glass sponges. Using a remotely operated vehicle, samples of an encrusting sponge with three color morphotypes (yellow, white, and mauve) were collected from the northern reef complex of the HSQCS-MPA. Spicule and DNA analyses of COI sequences revealed the white morphotype to be distinct from the previously described species, D. austini Lehnert, Conway, Barrie & Krautter, 2005 . Comparisons with other Desmacella samples collected from other regions in British Columbia waters since 1976 confirmed this to be a new species, which we describe here as Desmacella hyalina sp. nov. We also mapped the spatial distribution of the color morphotypes on the reefs and found that Desmacella spp. formed nearly 20% of live sponge cover at some sampling sites indicating its potential importance in the reefs. Our results expand on knowledge of the diversity of sponge epibionts in glass sponge reefs and highlight the importance of understanding cryptic species diversity especially for future monitoring in marine protected areas.

Collections of sponges by the late Dr. William C. Austin and the authors (N. McDaniel, R. Harbo and B. Ott) provided material for descriptions of new species from two genera of Poecilosclerida for shallow waters of Southern British Columbia, Canada and Northern Washington, USA: Lissodendoryx and Myxilla. There have been no new species of these two genera described for the Northeast Pacific since Laubenfels' work in central California (Laubenfels 1930, 1932) and Lambe's reports in 1893 to 1895 for Geological Survey of Canada sponge collections from British Columbia, Canada to the Bering Sea. We describe three new species of Lissodendoryx (Lissodendoryx) (Demospongiae, Poecilosclerida, Coelosphaeridae) and one new species of Myxilla (Myxilla) (Demospongiae, Poecilosclerida, Myxillidae): L. (L.) barkleyensis n. sp., L. (L.) littoralis n. sp., L. (L.) toxaraphida n. sp. and M. (M.) austini n. sp. Lissodendoryx (L.) barkleyensis n. sp. is cave-dwelling, has acanthostyles 112-260 µm, tornotes 107-177 µm, arcuate isochelas 8-28 µm and two sizes of sigmas 18-29, 26-55 µm. Lissodendoryx (L.) littoralis n. sp. fistulate habitus is adapted to muddy substrates similar to some Polymastia species also found commonly in the Northeast Pacific. It has subtylostyles 185-336 µm, tylotes 112-229 µm, arcuate isochelas 11-23 µm, and sigmas 30-75 µm. Lissodendoryx (L.) toxaraphida n. sp. is the only described Lissodendoryx species with raphides shaped like toxas. It has acanthostyles 140-286 µm, tornotes 143-195µm, arcuate isochelas 18-34 µm and toxiform raphides 65-156 µm. Myxilla (M.) austini n. sp. has a fistulate habitus and both tornote and tylote megascleres. It appears to be tolerant of low oxygen environments. Myxilla (M.) austini n. sp. has smooth to sparsely spined styles 193-353 µm, tylotes 153-221 µm, tornotes 174-260 µm, two sizes of anchorate isochelas 13-27, 42-81 µm, and two sizes of sigmas 13-47, 33-78 µm. All specimens were collected from shallow water (intertidal to 25 m).

Lambe described Myxilla lacunosa from a specimen from Vancouver Island. Lambe's sponge was subsequently placed in the subgenus Burtonanchora based on Lambe reporting smooth styles. A number of investigators, including the authors of this paper, report some styles with spines in Lambe's sponge. We redescribe Myxilla lacunosa based on re-examination of Lambe's holotype, and propose to place it in subgenus Myxilla based on the presence of spined styles rather than subgenus Burtonanchora which is defined as genus Myxilla with smooth styles.

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..

FIGURE 19. Prosuberites saanichensis n. sp. A, live specimens on brachiopods, scale bar 5 mm; B, tylostyle, scale bar 50 µm; C, head of tylostyle, scale bar 20 µm; D, pointed end of tylostyle, scale bar 20 µm.

Two new species of Demospongiae are described for British Columbia and adjacent waters in the family Axinellidae, Auletta krautteri sp. n. and Dragmacidon kishinensis sp. n. They represent range extensions for both of these genera. Both are fairly commonly encountered, A. krautteri below diving depths (87 to at least 300 m) and D. kishinensis in shallow water (intertidal to 30 m). We propose an amended genus diagnosis for Auletta to account for the variability among species in principal spicules that form the ascending tracts to be either oxeas, styles or strongyles rather than just oxeas.

FIGURE 12. Sphaerotylus raphidophora n. sp. A, whole specimen preserved in alcohol, scale bar 1 cm; B, section showing tracts of megascleres radiating out to ectosome with protruding exotyles, scale bar 2 mm; C, exotyles showing expanded and stylote end, scale bar 100 µm; D, detail of expanded end, scale bar 20 µm.