Carnivorous sponges from the Australian Bathyal and Abyssal zones collected during the RV Investigator 2017 Expedition Author Ekins, Merrick Author Erpenbeck, Dirk Author Hooper, John N. A. text Zootaxa 2020 2020-05-12 4774 1 1 159 journal article 22182 10.11646/zootaxa.4774.1.1 269cf599-428d-464d-8f21-994d69110c5c 1175-5326 3825140 B0C4A2F8-F2AB-4147-BB12-63720EEF2516 Asbestopluma ( Abestopluma ) maxisigma sp. nov. Figure 6 , Table 4 urn:lsid:zoobank.org:act: EC21238B-C8A3-461F-B58D-23BFAC13ABBC Material Examined : Holotype : QM G337488 off Jervis Bay , Station 56, New South Wales , Australia , 35 o 19’58.81”– 35° 19’55.2” S , 151 o 15’28.8”– 151°12’ 50.4” E , 2636– 2342 m , Beam Trawl , Coll. Merrick Ekins on RV Investigator , Cruise IN2017_ V03 , Sample 56–236, 29/v/2017 . Etymology : Named ‘maxi’ for the maximum sized sigmas this species has, in addition to the usual small sigmas common amongst other species in the genus. The name also honours the family of the senior author, ‘Max Ekins I–IV’, of which I and II being great grandfather and grandfather respectively, and III and IV being father and brother respectively. Distribution : This species is presently known only from type locality on the continental slope off Jervis Bay, New South Wales , Australia , at bathyal depth. Description: Growth form : An erect columnar pedunculate sponge with pinnate filaments projecting at right angles to the stem. This specimen is only 28 mm high, up to 2 mm wide, but the basal root and the top portion of the sponge are missing. On this station, the beam trawl was a fairly uniform muddy soft substrate. The filaments are up to 10 mm in length and 0.5 mm in width and project into four columns, with a right angle between them. Colour : Pale cream on deck and in ethanol. Ectosomal skeleton : The ectosome of both the stem and the filaments consist of soft tissue encrusted with anisochelae and sigmas. Endosomal skeleton : The axis of the stem and the filaments consists of tightly bound longitudinal tracts of mycalostyles. The mycalostyles are also arranged as buttresses providing support for the filaments that are also composed of the same styles and arise tangential to the stem (see Figure 6 H ), so that at their ends the mycalostyles converge onto the filament mycalostyles. In addition there are supplementary smaller very fine and short filament columns composed of the subtylostyles projecting at right angles to the stem and similarly converging with buttressing mycalostyles. FIGURE 6. Asbestopluma (Asbestopluma) maxisigma sp. nov. A. Anisochelae. B. Smaller size class of sigmas. C. Larger size class of sigmas. D. Large mycalostyle. E. Magnified ends of the mycalostyle depicted in D. F. Smaller subtylostyle. G. Magnified ends of the subtylostyle depicted in F. H. SEM showing the main stem longitudinal bundles of mycalostyles, as well as the major filaments buttressed with the large mycalostyles and the finer filaments composed of the subtylostyles I. Preserved holotype QM G337488. TABLE 4 . Comparative morphological and distributional data for all known species of Asbestopluma .

Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal attachment (LxW μm)	Chelae (L μm)	Sigmancistras Sigmas (L μm) (L μm) and other microscleres		Locality/ depth range
Asbestopluma (Abestopluma) maxisigma sp. nov.	this work	Erect columnar stipitate with a single axis and filaments projecting at right angles to the axis, basal attachment absent	28 x 2	Axis and filaments supported by tightly bound longitudinal tracts of mycalostyles, also arranged as buttresses tangential to the stem, bundles of smaller tylostyles also project tangential to the stem	mycalostyles 855-(1000)- 1130 x 15.7-(21.2)- 28.3	subtylostyles 427-(586)-805 x 3.7-(9.4)-15.3	absent	anisochelae 10.5–29.2	absent	larger sigmas continental 43.4-(54.0)- slope off 68.7 Jervis Bay, smaller New South sigmas 20.2- Wales, (27.7)- Australia, 37.8 bathyal
Asbestopluma (Asbestopluma) agglutinans Vacelet, 2006	Vacelet, 2006: 562 , Fig. 5	Arbuscular erect, short stem compared to long bipinnate body with biserial lateral filaments perpendicular to axis in two opposite series	40 x 0.8–1	Main axis of longitudinal bundles of fusiform (mycalo)styles surrounded by dense feltwork of acanthotylo- strongyles, axis of lateral filaments of smaller styles and similar feltwork of acantho- tylostrongyles, base with tangential styles to substrongyles	axial styles 1550–2100 × 30–35 acanthotylo- strongyles 65–165 × 0.8–2.3	axial mycalostyles 370–780 × 8.5–17 acantho- tylostrongyles 65–165 × 0.8–2.3	styles- substrongyles 220–535 × 15–42	anisochelae 1, 32–36 x 4.1–5 anisochelae 2, 9.8–10.5 x 0.8–1	23–28 x 2.3	absent	East Pacific Rise. Garrett Segment, bathyal

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal attachment (LxW μm)	Chelae (L μm)	Sigmancistras (L μm)	Sigmas (L μm) and other microscleres	Locality/ depth range
Asbestopluma (Asbestopluma) anisoplacochela Kelly & Vacelet, 2011	Kelly & Vacelet, 2011: 60 , Fig. 4	Arbuscular erect cylindrical ending in a slightly enlarged body bearing short lateral expansions laterally opposed	210 x 0.7–2	Axis and lateral expansions with longitudinally arranged mycalostyles, axis also with dense feltwork of acanthotylostrongyles, base absent	mycalostyles 650–1650 x 10–30 Acantho- tylostrongyles 130–310 x 2–3	undifferentiated mycalostyles	absent	anisochelae 10.5–10.8 anisoplacochelae 180–220	27–32 x 2.5–3	absent	Three Kings Ridge, New Zealand, bathyal
Asbestopluma ( Asbestopluma ) belgicae ( Topsent, 1901 )	Topsent, 1901: 23–27 , Pl. 1 Fig. 4, P l. III, Figs 1–7; Koltun 1964: 36 : Pl. VII, Figs 1–7; Hestetun et al. 2015: 6–8 , Fig. 4	Stipitate erect, long peduncle, multi-furcate basal holdfast, lateral filaments pinnate protruding from the main axis in series	35	Axis with bundles of mycalostyles arranged in a ring producing axial grooves, filaments bundles of subtylostyles pointing outwards, basal holdfast of mycalostyles, flexuous strongyles and smaller acanthostyles	mycalostyles 1010-(1449)-2070 x 17.3-(24.2)-31.4	subtylostyles 610-(734)-880 x 11.0-(15.1)-18.8	strongyles 460-(659)- 830 x 3.1- (6.0)-9.4 acanthostyles 127–(198)- 250 x 1.5	palmate anisochelae 11.0- (12.7)-14.1	27.0-(30.7)- 34.5	absent	Antarctica and western coast of Africa, bathyal

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal attachment (LxW μm)	Chelae (L μm)	Sigmancistras (L μm)	Sigmas (L μm) and other microscleres	Locality/ depth range
Asbestopluma (Asbestopluma) bihamatifera ( Carter, 1876 )	Carter, 1876 ; Hestetun, Tompkins- Macdonald & Rapp 2017: 4–6, Fig. 3	Arbuscular erect, short stem, bottle-brush filaments in 4–6 rows equally distributed around stem, branching root-like basal holdfasts	50–100 x 1–2	Axis of tightly packed mycalostyles with points toward apex, lower stem with outer layer of acanthotylostyles, filaments with overlapping subtylostyles	mycalostyles 653-(821)-935 x 17.3-(23.5)-31.4	subtylostyles 465-(633)- 754 x 12.1- (16.1)-20.4	arcuate- palmate anisochelae 40.7-(55.3)- 60.7 palmate anisochelae 8.6-(10.2)- 11.0	absent	North Atlantic, mesophoticbathyal
Asbestopluma (Asbestopluma) biserialis ( Ridley & Dendy, 1886 )	Ridley & Dendy, 1887: 75 , Pl. XIV Figs 2–3, Pl. XV Fig. 8; Levi 1993: 39 , Fig 14b	Stipitate erect, long stem with twisted axis, bifurcate mostly short filaments in a single row on opposing sides of upper stem, base not recorded	95–120 x 1	Dense spicular axis of mycalostyles- styles, outer layer of acanthotylostrongyles, filaments cored by subtylostyles	mycalostyles-styles 1 500–1900 x 8–20 acanthotylostrongyles 100–500 x 1–3	subtylostyles 375–1300 x 10–25	absent	palmate anisochelae 8–13	25–28	absent	SE Pacific, Kermadec Trench, Coral Sea off New Caledonia, and NW Pacific off Aleutian Islands, bathyal-abyssal

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal attachment (LxW μm)	Chelae (L μm)	Sigmancistras Sigmas Locality/ (L μm) (L μm) depth range and other microscleres
Asbestopluma (Asbestopluma) bitrichela Lopes, Bravo & Hajdu, 2011	Lopes et al. , 2011: 417 , Figs 7–8	Stipitate erect, bifurcated branches, very short lateral filaments, enlarged basal attachment	402 x 19	Axis with longitudinal tracts of styles-mycalostyles and also strongyles- anisostrongyles, filaments cored by perpendicular styles- subtylostyles, base with desmas and acanthotylostrongyles	styles- mycalostyles 913–1850 x 18–43 strongyles- anisostrongyles 100–1775 x 17–53	styles- subtylostyles 226–698 x 3–23	monocrepid desmas arcuate 300–1125 x 40–190 anisochelae acanthotylo- 58–100 strongyles 123–425 anchorate- x 5–8 unguiferate anisochelae 15–20		20–25	absent	Diego Ramírez Archipela go, South Chile, bathyal
Asbestopluma (Asbestopluma) caribica Hestetun, Pomponi & Rapp, 2016	Hestetun et al. , 2016: 525 , Fig. 4	Stipitate erect, very thin stem, with upper stem carrying 2 oppositely arranged rows of filaments, base not recorded	83–109 x 1	Axis with longitudinally arranged mycalostyles, filaments of subtylostyles perpendicular to stem, basal stem with acanthotylostyles	mycalostyles 990-(1194)-1426 x 18-(23)-33 acanthotylostyles 74-(114)-194	subtylostyles 320-(550)-660 x 8–(12)-14	absent	anisocerci -chelae 52-(64)-74 Palmate anisochelae 8-(10)-12	19-(26)-34	absent	Beata Ridge, Caribbean Sea, abyssal

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal Chelae (L μm) attachment (LxW μm)		Sigmancistras (L μm)	Sigmas (L μm) and other microscleres	Locality/ depth range
Asbestopluma (Asbestopluma) desmophora Kelly & Vacelet, 2011	Kelly & Vacelet, 2011: 62 , Figs 5–6	Arborescent erect, dichotomous bifurcate branching, short stem, long branches nearly fully covered in filaments, disc-like holdfast	up to 80 x 1.3–4.2	Basal attachment with densely packed desmas, axis of stem with styles or substrongyles lined by microtylostrongyles, axis of filaments with core of mycalostyles	styles 400–1500 x 12–38 microtylo- strongyles 30–138 x 2–2.5	mycalostyles 300–600 x 5–12	desmas 100–450 anisochelae 1, 25–46 anisochelae 2, 7.5–11		15–27.5	10–28	Seamounts on Macquarie Ridge (Australian EEZ), mesophoticbathyal
Asbestopluma (Asbestopluma) flabellum Koltun, 1970	Koltun, 1970: 190 , Figs 16.7– 16.10	Arbuscular erect, short stem, ‘bottlebrush’ filaments at apex of stem, base not recorded	10	Axis with tracts of polytylote tylostyles, filaments with shorter tylostyles	polytylote tylostyles 275–990 x 5–24	smaller tylostyles	absent	arcuate anisochelae 25–28	71–104	absent	NW Pacific, abyssal

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal Chelae (L μm) attachment (LxW μm)		Sigmancistras (L μm)	Sigmas (L μm) and other microscleres	Locality/ depth range
Asbestopluma (Asbestopluma) furcata Lundbeck, 1905	Hestetun, Tompkins- Macdonald & Rapp 2017: 7–9, Figs 4–5	Arborescent erect, repeated dichotomous branching with 2 opposite rows of filaments terminating in small bud-like enlargements, multi-furcate basal holdfasts	200 x 0.5–2	Branches with central core of longitudinally arranged mycalostyles, lower stem with outer layer of acanthotylostyles, filaments of subtylostyles	mycalostyles 333-(628)-968 x 6.3-(15.1)- 23.6	subtylostyles 279-(360)-475 x 4.7-(9.4)-14.1	acanthotylostyles arcuate-palmate 44-(73)-107 isochelae 39.3-(48.6)-62.6 palmate anisochelae 7.0-(9.2)-12.1		12.1-16.6- 22.7	absent	Arctic- North Atlantic, mesophotic- bathyal
Asbestopluma (Asbestopluma) gemmae Goodwin, Berman, Downey & Hendry, 2017	Goodwin et al. , 2017: 44–45 , Fig. 4	Stipitate erect, dichotomously branched thin stems, filaments small subterminal bud-like structures, base not recorded	60 x 0.5	Axis of stem with larger mycalostyles, bud-like filaments with smaller subtylostyles and also found on surface of stem	mycalostyles 1000–1202 x 18–32	subtylostyles 292–339 x 9–16	absent	anisochelae 1, 69–96 anisochelae 2, 17–31	9–14	absent	Shakleton Fracture Zone, Antarctica, bathyal

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal attachment (LxW μm)	Chelae (L μm) Sigmancistras (L μm)		Sigmas (L μm) and other microscleres	Locality/ depth range
Asbestopluma (Asbestopluma) gracilior ( Schmidt, 1870 )	Schmidt, 1870: 49 , Pl. V, Fig. 9; Van Soest 2017: 131–132 , Fig. 81	Stipitate erect, thin-branched tree-like, thick stalk, body bilaterally symmetrical branching filaments curved upwards to a pointed apex, base not recorded	450 x 3	Axis with thick bundles of mycalostyles, filaments with mycalostyles and subtylostyles, acantho- tylostrongyles echinate axial bundles forming a tangential ectosomal layer	mycalostyles 777-(988)-1140 x 22-(24.3)-26	polytylote subtylostyles 576-(671)-729 x 12-(14.4)- 16.5	acantho-tylostrongyles 61-(99)-132 x 1.5-(1.9)-2.5	palmate anisochelae 9-(11.3)-13	23-(25.4)-31	absent	Guyana Shelf, Gulf of Mexico, mesophotic
Asbestopluma (Asbestopluma) inexpectata Lopes & Hajdu, 2014	Lopes & Hajdu, 2014: 341–344 , Figs 7–8	Pedunculate- arbuscular erect, short stem, abundant filaments over most of the stem in regularly arranged in 1 lateral row either side of stem, enlarged globular basal holdfast	38 x 5	Axis and filaments with longitudinal and perpendicular tracts, respectively, of mycalostyles and subtylostyles, acanthotylostrong yles and desmas in basal holdfast	mycalostyles 472–1180 x 5–28 subtylostyles 205–523 x 3–15 smaller curved subtylostyles 60–95 x 5–8	undifferentiated	monocrepid desmas 369–657 x 25–50 acanthotylostrongyles 78–128 x 3–5	arcuate anisochelae 38–63 anchorate- unguiferate anisochelae 13–18	15–23	absent	Campos Basin and Florianopo lis, Brazil, mesophotic

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of Chelae basal attachment (L μm) (LxW μm)		Sigmancistras (L μm)	Sigmas (L μm) and other microscleres	Locality/ depth range
Asbestopluma (Asbestopluma) jamescooki Hestetun, Rapp & Xavier, 2017	Hestetun et al. , 2017: 173–175 , Fig. 6	Stipitate erect, single stem or dichotomously branched, two rows of short filaments, base not recorded	13 x 0.3	Axis with longitudinal tracts of mycalostyles, filaments with perpendicular tracts of subtylostyles	mycalostyles 466-(652)-822 x 14.1-(19.7)-25.8 subtylostyles 1, 637-(811)-933 x 15.9-(20.4)-28.7 subtylostyles 2, 356-(494)-719 x 6.5-(10.3)-14.3 subtylostyles 3, 223-(250)-299 x 3.8-(4.8)-7.0	subtylostyles 281-(383)-458 x 6.4-(10.4)-14	absent	arcuate anisochelae 25.6-(30.9)- 37.9 palmate anisochelae 7.2-(9.9)- 12.2	17.1-(20.1)- 23.6	absent	SW Indian Ocean Ridge, S Africa, bathyal
Asbestopluma (Asbestopluma) laminachela Hestetun, Rapp & Xavier, 2017	Hestetun et al. , 2017: 175–176 , Fig. 7	Pedunculate erect, subglobular basal holdfast, stem and spherical body with numerous filaments in all directions	6 x 1.5	Axis has solid tracts of larger subtylostyles extending to center of the body, subtylostyles in lower parts of the body project outwards parallel to the surface, filaments with parallel tracts of subtylostyles, base with hispid projecting subtylostyles	subtylostyles 1, 637-(811)-933 x 15.9-(20.4)-28.7 subtylostyles 2, 356-(494)-719 x 6.5-(10.3)-14.3 subtylostyles 3, 223-(250)-299 x 3.8-(4.8)-7.0	undifferentiated	undifferentiated palmate anisochelae 13.8-(15.4)- 17.2		absent	contorted sigmas 39.5-(46.7)- 54.1	SW Indian Ocean Ridge, S Africa, mesophotic

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal attachment (LxW μm)	Chelae (L μm)	Sigmancistras (L μm)	Sigmas (L μm) and other microscleres	Locality/ depth range
Asbestopluma (Asbestopluma) magnifica Lopes, Bravo & Hajdu, 2011	Lopes et al. , 2011: 424–427 , Figs 9–10	Arbuscular erect, anastomosing branching, short stem, furcate holdfast, numerous small filaments perpendiclar to stem	405–541 x 80–267	Axis of longitudinal tracts of styles with few (aniso) strongyles, axis of filaments cored by mycalostyles, acanthotylostrongyles present at the base	mycalostyles 513-995 10-33 (aniso)strongyles 123-410 38-60	mycalostyles 205–687 x 5–10 styles 205–268 x 5–15	acanthotylostrongyles 441–729 x 25–35	palmate anisochelae 1, 30–38 palmate anisochelae 2, 13–18	25–40	absent	Diego Ramírez Archipela go (south Chile), bathyal
Asbestopluma (Asbestopluma) monticola Lundsten, Reiswig & Austin, 2014	Lundsten et al. , 2014: 105–109 , Figs 2–3	Arborescent erect, dichotomous bifurcate branching, short stem, long branches nearly fully covered in filaments, disc-like holdfast	194–280 x 130	Axis of branches and stem with bundles of smaller mycalostyles, filaments with bundles of larger mycalostyles, large curved styles in basal cone	mycalostyles 705-(751)-797 x 23-(25.5)-27	mycalostyles 627-(687)-756 x 15-(17.5)-20	curved mycalostyles 382-(462.1)-540 x 32-(39.97)-48 Microacantho- tylostrongyle 87-(98.1)-109 x 1.3-(1.7)-2.1	palmate absent anisochelae 11-(11.8)-12.5		sigmas 21-(22.9)-24	Davidson Seamount and Monteray Canyon, California, bathyal

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal Chelae Sigmancistras attachment (LxW μm) (L μm) (L μm)		Sigmas Locality/ (L μm) depth range and other microscleres
Asbestopluma (Asbestopluma) obae Koltun, 1964	Koltun, 1964: 36–37 , Fig. 8	Known only from a fragment of a stalk,	150 x 1	Unknown	styles- subtylostyles 1100–1750 x 20–44	subtylostyles- tylostyles 330–650 x 8–14	acanthotylostrongyles palmate 23–25 85–170 x 2–4 anisochelae 10		absent	Wilkes Land, Australian Antarctic Territory, bathyal
Asbestopluma (Asbestopluma) pennatula ( Schmidt, 1875 )	Schmidt, 1875: 119 , Pl. 1, Fig. 4; Hestetun, Tompkins- Macdonald & Rapp, 2017: 9–11, Fig. 6	Stipitate erect, long stem, multi-furcate basal holdfast, pinnate with 2–4 rows of filaments in 1 or 2 rows on opposite sides of stem	250 x 1–3	axis of tightly packed mycalostyles with points towards apex, filaments with overlapping subtylostyles, holdfast with outer layer of acanthotylostyles	mycalostyles 500-(760)- 1010 x 9.4-(18.9)- 31.4	subtylostyles 372-(602)-810 x 6.8-(12.4)-22.0	acanthotylostyles 75-(117)-159	arcuate- 17.3-(21.2)- palmate 25.1 anisochelae 38.8-(53.1)- 73.5	absent	Atlantic Arctic, mesophotic- bathyal
Asbestopluma (Asbestopluma) pseudoisochela Hestetun, Rapp & Xavier, 2017	Hestetun et al. , 2017: 176–178 , Fig. 8	Stipitate erect, slender single-stem with rows of short filaments projecting in all directions from the center, globular basal holdfast	85 x 1.5	Axis with core of longitudinal mycalostyles, projecting filaments cored by subtylostyle bundles, desmas present in basal part the sponge	mycalostyles 570-(772)- 893 x 12.9- (20.6)-28.3	subtylostyles 1, 470-(584)-719 x 9.7-(13.5)-19.7 subtylostyles 2, 133-(176)-218 x 3.1-(5.5)-7.0 subtylostyles 3, 113-(321)-557 x 18.6-(25.8)-31.8	desmas 186-(318)-445	arcuate 15.2-18.9- anisochelae 22.6 1, 82.2-(95.2)- 107.6 arcuate anisochelae 2, 9.5-(11.9)- 14.1	absent	Southwest ern Indian Ocean Ridge, mesophotic- bathyal

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal attachment (LxW μm)	Chelae Sigmancistras Sigmas Locality/ (L μm) (L μm) (L μm) depth range and other microscleres
Asbestopluma (Asbestopluma) quadriserialis Tendal, 1973	Tendal, 1973: 34–35 , Figs 1–2	Stipitate erect, with 4 rows of paired branches on lateral sides, with numerous bud-like projection in between, long stem, base absent	75 x 1	Axis cored by styles, lower part of stem with acanthotylostyles, branches and filaments with styles-tylostyles	styles 480–960 x 6–25	styles 880–1040 x 12–25 subtylostyles 400–640 x 5–10	acanthotylostyles 75–125 x 1–3	arcuate anisochelae 35–45 palmate anisochelae 10–13	absent	sigmas 1, 75–125 sigmas 2, 28–38	NE Atlantic, abyssal
Asbestopluma (Asbestopluma) ramosa Koltun, 1958	Koltun, 1958 ; Koltun, 1959: 49–50 , Fig. 29	Arborescent erect, dichotomously branching in 1 plane, branches with closely spaced filaments, long stem and root like basal holdfast	250 x 12	Axis with compact bundles of mycalostyles, filaments perpendicular to axial skeleton, ectosome with acanthostylostyles.	styles- subtylostyles 468–904 x 10–29	undifferentiated	acanthotylostrongyles palmate 60–199 anisochelae 13–16		23–31	absent	Kuril Islands, Okhotsk Sea, NW Pacific, mesophoticbathyal
Asbestopluma (Asbestopluma) ramuscula Hestetun, Rapp & Xavier, 2017	Hestetun et al. , 2017: 178 , Fig. 9	Stipitate- arbuscular erect, dichotomo usly branching, with flattened stem with two opposite rows of very fine filaments, small basal plate	5–15 x 0.7	Axis of stem with longitudinal bundles of mycalostyles, filaments of subtylostyles perpendicular to stem, no special basal spicules	mycalostyles subtylostyles 351-(567)- 224-(265)-292 742 x 4.1-(7.1)-13.4 x 13.3-(19.8)- 32.5		undifferentiated	arcuate anisochelae 15.2-(19.7)- 26.9 palmate anisochelae 6.9-(10)- 11.3	11.9-15.7- 20	absent	Southwest ern Indian Ocean Ridge, mesophoticbathyal

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal attachment (LxW μm)	Chelae (L μm)	Sigmancistras (L μm)	Sigmas (L μm) and other microscleres	Locality/ depth range
Asbestopluma (Asbestopluma) rhaphidiophora Goodwin, Berman, Downey & Hendry, 2017	Goodwin et al. , 2017: 45–47 , Fig. 5	Pedunculate erect, thin stem with apical body forming a flattened, spiky circle composed of radiating columns of spicules, small circular basal attachment	33 x 16	Axis of stem with ascending columns of medium mycalostyles, body with radiating columns of larger mycalostyles, base with columns of smaller mycalostyles	mycalostyles 600-(1067)- 1753 x 21-(37)-50	mycalostyles mycalostyles 1087-(1879)-2962 408-(704)-965 x 14-(34)-45 x 20-(29)-45		palmate anisochelae 61–92	absent	sigmas 18–24 spined rhaphides 693-(1089)- 1374 x 3.4-(7)-8	Burdwood Bank, Tierra del Fuego, bathyal
Asbestopluma (Asbestopluma) rickettsi Lundsten, Reiswig & Austin, 2014	Lundsten et al., 2014: 109–112 , Figs 5–6	Arborescent erect, dichotomously branching, bottle-brush filaments, short stem with basal disc holdfast	217 x 124	Axis of branches and stem with mycalostyles, filaments with smaller mycalostyles, styles- anisostrongyles in basal disc	mycalostyles 916-(956)- 1006 x 18-(19.8)-22	mycalostyles 580- (642.6)-705 x 11-(14)-17	styles- anisostrongyles 502-(555)-608 x 20-(26.6)-32 microacantho- tylostrongyles 93-(102.6)-112 x 1-(1.5)-2	Anisochelae 1, 48–59 Anisochelae 2, 9–10	absent	sigmas 16–18	northwest of La Jolla, California, bathyal
Asbestopluma (Asbestopluma) ruetzleri Hestetun, Tompkins- Macdonald & Rapp, 2017	Hestetun, Tompkins- Macdonald & Rapp, 2017: 11–14, Fig. 8	Stipitate erect, long stem, pinnate upper stem with 4 rows of filaments paired on opposite sides, basal attachment unknown	140 x 2–3	Axis tightly packed mycalostyles with points towards apex, lower stem with outer layer of acanthotylostyles, filaments of subtylostyles	mycalostyles 581-(731)-918 x 16.0-(23.8)- 34.2	subtylostyles unknown 514-(638)-810 x 11.0-(15.8)-20.3 acanthotylostyles 75-(111)-142		arcuate anisochelae 42.7-(49.3)- 57.2 palmate anisochelae 8.6-(10.6)-12.6	20.3-(23.0)- 31.6	absent	NW Atlantic, mesophotic- bathyal

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal attachment (LxW μm)	Chelae (L μm)	Sigmancistras (L μm)	Sigmas (L μm) and other microscleres	Locality/ depth range
Asbestopluma (Asbestopluma) sarsensis Goodwin, Berman, Downey & Hendry, 2017	Goodwin et al. , 2017: 47–49 , Fig. 6	Arborescent erect, flattened anastomosing branching, filaments project from sides of branches, no basal plate	110 x 10	Stem with parallel ascending bundles of mycalostyles, filaments with bundles of a similar size projecting at right angles, dense mesh of mycalostyles and acanthotylo- strongyles.	mycalostyles 675–864 x 17–40	undifferentiated	mycalostyles 567–807 x 24–36 Aniso-acanthotylo- strongyles 113–154 x 2–3	Palmate anisochelae 11–14	11–14	absent	Seamounts off Tierra del Fuego, meophotic -bathyal
Asbestopluma (Asbestopluma) unguiferata Hestetun, Rapp & Xavier, 2017	Hestetun et al. , 2017: 178–180 , Fig. 10	Arbuscular erect, dichotomo usly branching stem with two rows of tightly set filaments, small basal plate	14 x 1	Axis main stem with longitudinal mycalostyles and layer of confusedly arranged subtylostyles surrounding stem, filaments with perpendicular subtylostyles	mycalostyles 445-(588)- 718 x 11.8- (19.2)-32.5	subtylostyles 224-(271)-323 x 5.3-(7)-13.4	Acanthosubtylo- strongyles 54-(65)- 79	arcuate/ unguifer ate anisochelae 20.1-(21.7)- 24 anchorate/ unguiferate anisochelae 9-(10.5)- 11.7	11.6- (13.9)- 16.1	absent	Southwest ern Indian Ocean Ridge, bathyal
Asbestopluma (Asbestopluma) voyager Lopes & Hajdu, 2014	Lopes & Hajdu, 2014: 344–346 , Fig. 9	Pedunculate- stipitate erect, short peduncle, finger-or feather-like filaments in 2 lateral rows, slightly widened basal holdfast	12–16 x 1–1.6	Axis and filaments with longitudinal and perpendicular tracts of mycalostyles, respectively, acanthotylostrongyles form basal holdfast	mycalostyles 236–944 x 5–15	undifferentiated	Acanthotylo- strongyles 38–118 x 3–5	Palmate anisochelae 8–15	20–45	absent	Campos Basin, SE Brazil, mesophotic

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal attachment (LxW μm)	Chelae (L μm)	Sigmancistras (L μm)	Sigmas (L μm) and other microscleres	Locality/ depth range
Asbestopluma (Asbestopluma) wolffi Lévi, 1964	Lévi, 1964: 75 , Fig. 23; Koltun 1970: 188 , Pl. 14, Figs 5–7	Stipitate- arbuscular erect, long stem with apical bottle- brush of filaments, base bulbous	55 x 1–2	Axis of stem with longitudinal bundles of styles, filaments with longer styles inserted parallel to stem	styles 1600–2900 x 20–32 styles 374–1200 x 9–15	styles 1500–3800 x 10–18	absent	palmate anisochelae 14–19	absent	absent	Kermadec Trench, SW Pacific, hadal
Asbestopluma (Helophloeina) delicata Lopes, Bravo & Hajdu, 2011	Lopes et al. , 2011: 428–431 , Fig. 12	Arborescent erect, short stem, basal holdfast disc, dichotomous branching, long filaments in single rows either side of branches	4 x 1	Axis of large styles/mycalostyles arranged longitudinally, also oxeas and styles/ anisostrongyles occur in axis, microstrongyles form a confused outer layer, mycalostyles core filaments, also with confused outer layer of microstrongyles, styles/ anisostrongyles and spear-shaped microtylostyles present in base	oxeas 216-(424.6)-77 x 5-(10.0)-20 styles/mycalostyles 420-(552.4)-70 x 8 8-(18.0)-30	mycalostyles/ subtylo styles 185-(314.3)-585 x 5-(9.4)-13	styles/oxeas/ anisostrongyles 125-(256.8)-510 x 13-(19.5)-28	palmate isochelae 23-(31.3)- 43 palmate anisochelae 10-(10.7)- 13	18-(21.9)- 25	microstrongyles 30-(51.3)-75 x 5-(7.3)-8 microtylostyles 23-(26.3)-30 x 8	Diego Ramírez Archipela go (south Chile), bathyal

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Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal Chelae attachment (LxW μm) (L μm)		Sigmancistras (L μm)	Sigmas (L μm) and other microscleres	Locality/ depth range
Asbestopluma (Helophloeina) formosa Vacelet, 2006	Vacelet, 2006: 564–567 , Figs 6–8	Arborescent erect, fan- shaped in a single plane, short stem with repeated dichotomous branches, short basal plate	80 x 160	Axis of large styles mixed with few substrongyles near base, dense cover of microstrongyles on lateral sides of flattened branches, lateral processes with axis of small styles perpendicular and protruding through layer of microstrongyles, basal stem with microtylostyles	axial styles 200–1025 × 20–45 axial substrongyles 80–500 × 15–30 microstrongyles 25–60 × 5–7	styles 180–350 × 7–9	microtylostyles 25–45 × 4–7	arcuate anisochelae 72–90 palmate anisochelae 10–15	absent	absent	North Fiji Basin, bathyal
Asbestopluma (Helophloeina) keraia Goodwin, Berman, Downey & Hendry, 2017	Goodwin et al. , 2017: 49–50 , Fig. 7	Arborescent erect, dichotomously branched, branches flattened, filaments on lateral sides of all branches, no basal attachment present	15 x 1–2	Axis of stem with larger mycalostyles with micro-strongyles, filaments corerd by single smaller style, base with mass of styles, microstrongyles and microtylostrongyles	mycalostyles 562–678 x 15–30	mycalostyles 208–265 x 5–10	mycalostyles 209–606 x 20–39 strongyles 37–53 x 5–12 anthomicrotylostrong yles 22–32 x 3–8	arcuate anisochelae 32–43 palmate anisochelae 8–11	Drake Passage, Sars Seamount, bathyal

...Continued on the next page TABLE 4 . (Continued)

Species	Reference	Morphology	Total height x width (mm)	Skeleton	Spicules of main axis (LxW μm)	Spicules of lateral filaments or body (LxW μm)	Spicules of basal attachment (LxW μm)	Chelae (L μm) Sigmancistras (L μm)		Sigmas (L μm) and other microscleres	Locality/ depth range
Asbestopluma ( Helophloeina ) stylivarians ( Topsent, 1929 )	Topsent, 1929: 1–8 , Figs 1–6	Stipitate- arbuscular erect, apical bottle-brush filaments, long stem, no basal attachment present	8	Axis of stem with bundles of styles and oxeas, filaments cored by subtylostyles, base with monocrepidial desmas	styles 470–500 x 11 oxeas 425–525 x 15	sybtylote-polytylote styles 290–310 x 4–6	desmas 435–630 x 15–20	palmate absent anisochelae 11		microsubtylostyles 11–12 x 5 microstrongyles 23–95 x 1–3	Canary Islands, NE Atlantic, bathyal

Megascleres: Styles of two types in two statistically significant size classes in length and width (P<0.0001). Large mycalostyles, thickest at the middle of the spicule and tapering at both ends (855-(1000)-1130 μm x 15.7- (21.2)-28.3 μm, n=47). Smaller subtylostyles with slightly swollen bases and tapering to fine points (427-(586)-805 x 3.7-(9.4)-15.3 μm, n=57). Microscleres : Arcuate anisochelae, head with the lateral alae fully fused to the shaft and a large frontal alae significantly detached from lateral alae, foot with two fully fused nearly atrophied lateral alae and a single larger frontal ala with a tooth-like termination (Length 10.5-(13.1)-16.1 μm, large frontal alae width 2.3-(3.3)-4.2 μm, small lat- eral alae width 2.2-(2.8)-3.7 μm, n=62). Sigmas, predominantly s-shaped, fewer c-shaped, in two size classes: larger sigmas (43.4-(54.0)-68.7 μm, n=40), smaller sigmas (20.2-(27.7)-37.8 μm, n=71). Molecular data : The 28S sequence of QM G337488 is provided in the Sponge Barcoding Database under accession number SBD#2311 and the molecular difference to other congenerics displayed in Figure 3 . Remarks : This species differs from other known species of Asbestopluma in having two sizes of sigmas and only one type of small anisochelae ( Table 4 ). Asbestopluma (A.) maxisigma sp. nov. appears to be most closely related to A. (A.) biserialis ( Ridley & Dendy, 1886 ) , known from the South Pacific (SE Pacific, Ridley & Dendy 1886 ; Kermadec Trench, Lévi 1964 ; and the Coral Sea off New Caledonia , Lévi 1993 ), and the North Pacific (south of the Aleutian Islands, Koltun 1970 ), from bathyal and abyssal depths. Both species have vaguely similar pinnate pedunculate morphologies but the new species has twice as many columns of filaments (i.e. four as opposed to two). Mycalostyles-styles of the axial skeleton are much shorter and thinner in the new species, which also possesses two size classes of sigmas, but it lacks the acanthotylostrongyles found in A. (A.) biserialis . The smaller anisochelae of A. (A.) desmophora Kelly & Vacelet, 2011 , from the mesophotic-bathyal depths of the Macquarie Ridge seamounts, are similar in geometry and size to those of the present species, both having a tooth-like termination on the frontal ala of the foot, but the former also has a second category of larger anisochelae with a different geometry, has only one size category of small sigmas, and also possesses sigmancistras. The pedunculate gross morphology of A. (A.) maxisigma sp. nov. is also very different from the arborescent A. (A.) desmophora , the latter also having basal desmas and microtylostrongyles. In its gross morphology this new species also resembles A. (A.) belgicae ( Topsent, 1901 ) , (qv Lopes et al. 2011 , Hestetun et al. 2015 , Goodwin et al. 2017 ). However, A. (A.) maxisigma sp. nov. has the following differences: much larger styles, two size categories of styles, larger anisochelae and two categories of sigmas. Asbestopluma (A.) sarsensis Goodwin et al. , 2017 is similar in spiculation to A. (A.) belgicae , and also differs from the present species for the same reasons given above, in addition to also having a very different growth form. Asbestopluma (Asbestopluma) obae Koltun, 1964 from Wilkes Land, Antarctica differs from the present species in having acanthotylostrongyles, lacking the larger sigmas, and lacking horizontal filaments.