Cladorhiza poritea, Ekins & Erpenbeck & Hooper, 2020

Ekins, Merrick, Erpenbeck, Dirk & Hooper, John N. A., 2020, Carnivorous sponges from the Australian Bathyal and Abyssal zones collected during the RV Investigator 2017 Expedition, Zootaxa 4774 (1), pp. 1-159 : 72-73

Cladorhiza poritea sp. nov.

Figures 9 & 10 , Tables 5 & 7

urn:lsid:zoobank.org:act:1137946D-9779-49F1-A6E8-78DD9F4C85C3

Material Examined: Holotype: QM G337401 , off Fraser Island , Station 109, Queensland, Australia, 25 o 13’15.6”– 25° 15’10.8” S, 154 o 9’50.4– 154° 11’ 31.2” E, 4006– 4005 m, Beam Trawl, Coll. Merrick Ekins on RV Investigator, Cruise IN2017_ V03 , Sample 109-126.1, 11/vi/2017.

Paratypes: QM G337544 same collection details as the holotype, Sample 109–126 ; QM G337437 off Freycinet Peninsula , Station 6, Tasmania, Australia, 41° 37’ 32.0”– 41° 41’ 21.2” S, 149° 33’ 5.4”– 149° 35’ 3.5” E, 4022–4052 m, Beam Trawl, Coll. Merrick Ekins on RV Investigator, Cruise IN2017_ V03 , Sample 6-158.1, 18/v/2017 .

Comparative Material: Cladorhiza mirabilis ( Ridley & Dendy, 1886) , type of Axoniderma mirabile , BMNH 1887.5 .2.141 and BMNH 1891.10 .3.49 (see below) .

Etymology: This species is named for the shape of its pseudoamphiasters, which when viewed from above, resemble the shape of the corallites in the scleractinian Porites .

Distribution: This species is currently known only from the East Coast of Australia, at abyssal depth.

Description:

Growth form: An erect, unbranched, pedunculate ‘crinorhizoid’, parasol-shaped sponge with long filaments extending outwards and downwards from the body at an angle of between 15 and 45 degrees ( Figure 9 K–M). In the holotype the filaments are up to 30 mm long and 0.5 mm in width. The body of the sponge is 13 mm across the base. The stem of the sponge is currently 37 mm long, but is broken so the total length is unknown, as are the nature of the basal attachment structures. The stem is 1.1 mm thick and lacks any other structures. The top of the sponge is an acuminate papillate shape, tapering to a point. The paratype G337544 is in slightly worse condition with many of the filaments broken, and the endosome around the apices removed revealing the core of the vertical axis of styles protruding directly up from the stem through the sponge body. This paratype has a similar parasol, with the main body 10 mm across base and with 20 mm long processes. The stem of this paratype is even more damaged than the holotype and is 11.6 mm long x 1.5 mm wide. The paratype QM G337437 is a juvenile, with a stem of 1 mm in width and 50 mm in length, whilst the double conical body is 6 mm in diameter and the almost horizontal filaments are only 10 mm in length. None of the specimens had a basal attachment intact.

Colour: The sponges are cream on deck and in ethanol.

Ectosomal skeleton: The ectosomal skeleton is a thin membrane containing the anisochelae and the pseudoamphiasters ( Figure 10 A–F), which is tightly bound to a sheath like layer of styles ( Figure 10 D, F ). On the body of the sponge the pseudoamphiasters are on the external surface and the anisochelae are underneath ( Figure 10 B ). On the stem the pseudoamphiasters are also on the outside ( Figure 10 C ). In contrast, on the filaments, the anisochelae are on the external surface and the pseudoamphiasters are underneath ( Figure 10 E )

Endosomal skeleton: The endosomal skeleton consists of the mycalostyles in a single concentrated longitudinal bundle. In both the stem and the filaments this central bundle is surrounded by a sheath including all three styles ( Figures 10 D and 10 F respectively). The body of the sponge consists of the individual bundles forming the filaments radiating from the body axis ( Figure 10 A , 9 J ).

Megascleres: Styles are in three size groups with the largest two sizes are nearly oxeote and have their greatest width at the central and both ends tapering considerably ( Figure 9 D–I). The smallest styles are often slightly curvaceous. The large mycalostyles mainly occur in the axis of the stem and filaments ( Table 7 ). The middle and smaller size styles are mainly in the surrounding sheaths ( Figure 10 D, F ).

Microscleres: ‘Unguiferate’ anchorate anisochelae are tridentate apically and tridentate basally ( Figure 9 A ). Pseudoamphiasters are asymmetrical, with 4–7 alae on each end ( Figure 9 B, C , Table 7 ).

Molecular data: We were unable to compare our material of C. poritea sp. nov. to C. hubbsi as the holotype (Scripps P675, Acc. No. 1969.003,) of the latter was fixed in formalin. Nor were we able to extract DNA from the ancient lectotype of C. mirabilis , and Koltun’s (1970) specimen from the North Pacific was inaccessible. The 28S sequences of QM G337401, G337437 and G337544 are provided in the Sponge Barcoding Database under accession numbers SBD#2312, 2313 and 2315 and the molecular difference to other congenerics displayed in Figure 3 .

Remarks: Of the four parasol-shaped species of Cladorhiza bearing pseudoamphiasters ( C. mirabilis , C. hubbsi , C. mexicana , and the present species), C. mexicana and C. poritea sp. nov. are the only two species in which their pseudoamphiasters are asymmetrical. However, in the case of C. poritea sp. nov., this asymmetry is due to the possession of 4–7 alae on the apical end and only 3 alae on the basal end, with all alae of approximately similar dimension. Conversely, pseudoamphiasters of C. mexicana have 5 alae each end, but alae are slightly longer on the apical than the basal end, and the species also has sigmancistras in addition to the usual Cladorhiza unguiferate anisochelae ( Lundsten et al. 2017).

Cladorhiza poritea sp. nov. differs from C. mirabilis morphologically by having an acuminate tip, by not having the spicular processes protruding through the papilla, and having a much larger base of the parasol (excluding filaments). It differs most substantially by the difference in size of the pseudoamphiasters ( Table 5 ). This new species has a similar shallow conical angle of filaments to C. mirabilis which is very different from the almost vertical orientation of C. hubbsi . It also differs from C. hubbsi by having the acuminate tip to the parasol, rather than the flattened apex, and lacking the ovoid posterior swelling. The filaments of the current specimens range from 5 to 30 mm and are most likely significantly longer, but were damaged during collection; these are slightly smaller than those of C. hubbsi . This new species lacks the four different sizes of styles, and has styles smaller than those found in C. hubbsi . In addition this species lacks the sigmancistras of C. hubbsi . This species differs from C. australis sp. nov. in lacking the larger ‘cleistochelate’ anisochelae but share similar unguiferate anisochelae of similar dimension and morphology.

Figures

FIGURE 3. Maximum-likelihood phylogram of the DNA sequences of this study in comparison with other, published cornivorous sponges. Sequences from taxa of this study are in bold. Number at the branches are RAxML rapid bootstrap values. Numbers following the taxa are either QM registration numbers (QM G3xxxxx) or NCBI Genbank accession numbers. Scale bare are substitutions per site. Please note that the reconstruction does not represent a phylogeny as due to the variability of the 28SrRNA gene C-Region barcoding marker no unambiguous alignment is possible and clipping ambiguous sites would remove diagnostic characters for taxon distinction. The tree therefore indicates molecular differences rather than a robust phylogeny.

FIGURE 9. Cladorhiza poritea sp. nov. A. Tridentate ‘unguiferate’ anisochelae. B. Asymmetrical pseudoamphiaster. C. Variation in the alae of the pseudoamphiasters. D. Large mycalostyle. E. Magnified ends of the mycalostyle illustrated in D. F. Medium styles. G. Magnified ends of the style illustrated in F. H. Small styles. I. Magnified ends of the style illustrated in H. J. Section through the body and stem of the sponge with one of the filaments on the right. K. Paratype QM G337437. L. Holotype QM G337401. M. Paratype QM G337544.

FIGURE 10. Cladorhiza poritea sp. nov. A. Body of the sponge showing the upper and lower ectosomal surface with the endosomal radiating mycalostyles in between, there are two of the filaments which have been inadvertently folded back over the sponge body. B. Magnified body surface showing the abundant pseudoamphiasters, and the underlying anisochelae. C. Stem showing the encrusting pseudoamphiasters in the ectosome. D. L.S. stem interior with the pseudoamphiaster crust and the styles forming an outer sheath, and an internal cored of styles. E. External layer of the filaments with the anisochelae exterior to the pseudoamphiasters. F. L.S. filament interior showing a sheath of styles similar to the stem and a hollow core.

Tables

TABLE 7. Spicule dimensions (µm) of the holotype and paratypes of Cladorhiza poritea nov. sp.

Specimen Pseudoamphiasters	‘Unguiferate’ anisochelae	Mycalostyles	Medium Styles	Small Styles
QM 93-(144)-168 G337401 x 24.8-(33.3)-39.9, Holotype shaft 6.1-(10.5)-14.2, n=58	23.7-(30.2)-35.2 x 1.6-(2.7)-4.0, n=77	1600-(2425)-3640 x 22.8-(40.0)-58.1, n=50	1300-(1666)-2200 x 16.6-(23.3)-29.9, n=33	582-(1280)-1850 x 6.3-(17.5)-23.9, n=26
QM 126-(154)-176 G337544 x 8.22-(11.5)-15.3, Paratype n=64	19.8-(30.9)-36.2 x 1.8-(2.7)-3.8, n=59	1810-(2717)-6650 x 29.8-(45.7)-75.0, n=45	1420-(1680)-2030 x 20.0-(24.9)-27.1, n=38	122-(1103)-1510 x 11.3-(18.1)-26.6, n=31
QM 105-(131)-154 G337437 x 7.9-(11.3)-14.4, Paratype n=57	22.0-(30.4)-33.2 x 1.6-(2.8)-4.2, n=55	1900-(2259)-2960 x 30.4-(42.8)-61.3, n=35	1140-(1458)-1770 x 19.8-(24.8)-28.1, n=18	523-(825)-1060 x 8.4-(17.8)-23.9, n=25