Pheronemoides curvipentactin, Lin & Xinzheng & Kwen-Shen, 2020

Lin, Gong, Xinzheng, Li & Kwen-Shen, Lee, 2020, Phylogeny of two new pheronematid sponges from the Caroline Seamount and South China Sea, Contributions to Zoology 89 (2), pp. 175-187 : 181-186

Pheronemoides curvipentactin sp. nov. Pacific Ocean (21º13.2041′N, 121º33.7489′E), 29

( figs. 3–4 , table 3) May 2013, Agassiz trawl, 517m depth.

Description. Specimen is curved ( fig. 3A ).

Material examined. Holotype: NMNS-8130- Dermal surface and atrial surface are on op-

001, Lanyu Township , Taitung County, Taiwan, posite sides Downloaded. Sponge from only Brill.com has12small /12/2023amount 03:06:16 PM

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of basalia left when collected. In addition, tangential rays (length: 177–251 µm) and one there is no available natural living picture of spindle-like pinular ray (length:36–63 µm), are the sponge. From the remaining body shape, slenderer than the dermalia. Atrialia of spe-

we inferred that the sponge has a typical body cial form are pentactins which have a sparsely form of Pheronemoides : when viewed from spined pinular ray with round or tapering terabove, it is fan-shaped ( fig. 3B ), when viewed minal curved ray (length: 140–261 µm), and from one side, there may be a big hollow be- four smooth tangential rays (length: 40–124 tween the dermal surface and basalia. The di- µm) ( fig. 4G–H ). Crooked pentactins ( fig. 4F ) ameter of the sponge is 240 mm. Marginalia withasmoothprimaryray,twosmoothtangen-

are present at the boundary between the atri- tial rays, a curved pinular tangential ray with al and dermal areas, protruding several centi- a large hooked terminus, and a smooth tanmeters from the body surface. Meshes of atrial gential ray with an expanded terminus bearareas and dermal areas are inconspicuous. Ba- ing thin teeth were also observed. This kind salia may be located on the dermal surface, of curved pentactin has not been observed in and only few basal spicules can be observed. other pheronematid species. Basalia are two- Spicules. The choanosomal pentactins toothed anchors (diameter 364–609 µm) and

( fig. 4A ) have smooth proximal rays and tan- monaxones (probably diactins). The shaft of gential rays (length: 404–4826 µm). Dermalia anchors are ordered as smooth, spiny, smooth are pinular pentactins ( fig. 4B–C ) with tan- and tapering apex from the proximal part gential rays (length: 89–297 µm) covered with to distal part ( fig. 4O–Q ). According to marspines and pinular rays (length: 43–77 µm) ginal spicule of other pheronematida species,

that are spindle-like and bushy with spines. though we only observed the shaft and apex Atrialia include normal and special pentactins. of marginalia ( fig. 4R–S ), we infer that they are

The normal forms ( fig. 4D–E ) with four spiny probably scepters Downloaded and from/or Brill diactins.com 12. / The 12/2023 width03:06:16PM via Open Access. This is an open access article distributed under the terms of the CC-BY 4.0 License. https://creativecommons.org/licenses/by/4.0/

of marginalia are 16–37 µm. Uncinates are of Microscleres consist of microamphidiscs two types: macrouncinates ( fig. 4I ) and mi- and microdiactins. Microamphidiscs ( fig. 4M ) crouncinates ( fig. 4J ).Macrouncinates (length: have smooth shafts, with total length of 27–42 4018–4355 µm) are covered by many tiny barbs µm, umbel length of 8–10 µm and umbel width on the shaft. Microuncinates (length: 175–366 of 7–10µm. The number of microamphidiscs µm) are thin with tiny spines on the shaft is small, and their palmate head reprsents 28 ( fig. 4K ) and a sharp terminal ( fig. 4L ). % of the Downloaded total length from. Microdiactins Brill.com 12/12/2023 (fig. 4N) 03:06:16PM

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https://creativecommons.org/licenses/by/4.0/ have long teeth and their total length is 118– Remarks. Although the new specimen is

157 µm. incomplete, and a hollow between the atrial Etymology. Curvipentactin from curv and dermal surfaces is not observed, the body (meaning curved), pent (meaning five), and is arched, and we can infer that its basalia are aktis (meaning rays), refers to this species not positioned Downloaded exactly from at Brill the.com centre 12/12/2023 of the 03:06:16PM containing curved pentactin spicules via. Open Access body. This is but an amesially open access article on the distributed dermal of the CC-BY surface under 4.0 the License. terms. https://creativecommons.org/licenses/by/4.0/

Therefore, we infer that the new species be- explored by Kersken's (2018) and Dohrmann's longs to Pheronemoides . The new species can (2018). And they have obtained similar phylobe easily distinguished from its congeners by genetic tree. In our study, we added the mopossessing special pentactine atrialia with lecular data of Poliopogon distortus and the round terminal or tapering terminal curved two new species, and a more comprehensive pinular rays and crooked pentactins. Addi- tree is provided. Our tree was generally contionally, the new species contains macroun- sistent with the previous results except the cinates and microuncinates while P. fungo- status of Semperella schulzei which was sister sus contains three types of uncinates and P. to Semperella jialongae + Poliopogon + Schulz crustiformis contains macrouncinates and eviella while it was clustered to Pheronema + mesouncinates. Sericolophus + Pheronemoides in the previous Molecular data. The phylogenies of BI and studies. This was probably due to the different

ML analyses were highly congruent. The phy- choices of alignment and substitution models, logeny based on 28SrRNA and 16SrRNA ( fig. 5 ) the molecular sequences of three additional shows that the two new species and P. fun- species, as well as one or two reduced mogosus forms into a clade with the exclusion lecular markers used in our analysis. Though of other pheronematids, thus supporting the there were some differences, our tree revealed family assignment, with support values>50 same relationship among the different genera for both the ML and BI analyses. of Pheronematidae as the previous studies, as well as the genus Semperella was a non-mono-

phyletic group.More species of definitive Sem-

Discussion perella are need to be sequenced in further studies to elucidate the status of this genus.

The phylogeny of the family Pheronemati- The Downloaded seven genera from Brill of.com Pheronematidae 12/12/2023 03:06:16PM dae through molecular approaches via had Open been Access. This Gray is, an 1870open are access often article distinguished distributed of the CC-BY from under 4.0 the each License terms. https://creativecommons.org/licenses/by/4.0/

other mainly by their external body shape, P. curvipentactin sp.nov. and P.fungosus exhibit whereas the morphologies and diversity of a closer relationship than P. crustiformis . Eco-

the spicules are less important (Tabachnick logically, P. curvipentactin sp. nov. and P. fun-

& Menshenina, 2002). Aproaches on the phy- gosus occur at the hard bottom on seamounts logeny of Pheronematidae based on mor- in the northwestern Pacific Ocean, while phology were explored once (Tabachnick & P. crustiformis sp. nov. occurs in the South Menshenina, 1999; Dohrmann et al., 2017). In China sea (substrate unknown due to the our tree, Pheronematidae is divided into two absence of a natural living image). Morphoclades. In one clade, Pheronema is sister to logically, only P. crustiformis sp. nov. exhib- Sericolophus + Pheronemoides . This is consis- its special pentactine atrialia, which makes tent with Tabachnick et al. (1999), who consid- it is easily distinguished from the others er Sericolophus to have evolved independently species.

in relation to Pheronema species, and Gong Forty-eight valid species of pheronematid et al. (2017), who recognized Pheronemoides have been reported ( Van Soest et al., 2019);

has a closed relationship with Pheronema and here, we only include 6 valid species in our Sericolophus . The other clade included Sem- tree (without the two new species and two perella, Poliopogon and Schulzeviella , which species that were unable to be classified at differed from the results of Dohrmann, who the species level). Therefore, more taxon covinferred that Schulzeviella was the sister group erage and molecular markers will be needed to the remaining pheronematids (Dohrmann in future studies to explore the phylogeny of et al., 2017). Since the phylogeny based on Pheronematidae .

molecular data was not consist with the morphology-based hypotheses, the special morphology of different genera within Phero- Acknowledgements nematidae may not be enough to treated as a reliable synapomorphy. And the unique mor- Special thanks to Dr. Kuidong Xu (Institute phological characteristics (i.e., the body being of Oceanology, Chinese Academy of Scibilaterally symmetrical or not, the atrial cavity ences, Qingdao) for providing the deep-sea being open or closed, atrialia being a common sponge specimens and the in situ pictures.

surface or not and basalia in a compact tuft We are grateful to the crews of the R/V Ke or a broad tuft) used to identify pheronema- Xue for their support in collecting the deep-

tida species into different genera might need sea sponge specimens during the cruises.

refinement. We also thank the editor and the reviewers Pheronemoides , which is fan-like, exhibit an for helping to improve the manuscript. This atrial concave side and a dermal convex side work was supported by the National Natural without basalia ( fig. 2 ). It shows a typical body Science Foundation of China (No. 41706188), shape similar to Poliopogon species. When we Science & Technology Basic Resources Invesestablished the genus, there was confusion tigation Program of China (No. 2017FY100804), about whether the genus was effectively de- the National Key R&D Program of China (No.

fined according to morphological approaches. 2018YFC0309804), the Senior User Project of

In our tree, Pheronemoides and Poliopogon are RV KEXUE (No. KEXUE2018G22), the China distant, and all the species of Pheronemoides Ocean Mineral Resources Research and Devel-

and Poliopogon were grouped together, which opment Association Program (No. DY135-E2 proves that Pheronemoides is a valid genus. -3-04). Downloaded from Brill.com 12/12/2023 03:06:16PM via Open Access. This is an open access article distributed under the terms of the CC-BY 4.0 License. https://creativecommons.org/licenses/by/4.0/

Figures

FIGURE 2 Spicules of holotype MBM286618 of Pheronemoides crustiformis sp.nov.A, choanosomal pentactin; B, the anchor of basalia; C, atrial pinular pentactin; D, dermal pinular pentactin; E–G, micramphidiscs; H, microdiactin I; I, microdiactin II; J, shaft of macrouncinate; K, shaft of mesouncinate; L–N, Sceptre; O–P, the anchor of basalia.

FIGURE 3 Holotype NMNS-8130-001 of Pheronemoides curvipentactin sp. nov. A, the external morphology of dermal areas (scale bar = 5 cm); B, the external morphology of atrial areas.

FIGURE 4 Spicules of holotype NMNS-8130-001 of Pheronemoides curvipentactin sp. nov. A, choanosomal pentac- tin; B–C, dermal pinular pentactins; D–H, atrialia:D–E, pinular pentactins; F, crooked pentactin; G–H, special pentactins; I, shaft of macrouncinate; J, microuncinate; K, shaft of microuncinate; L, terminal of microuncinate; M, micramphidisc; N, microdiactin; O–Q, the anchor of basalia; R–S; marginalia.

FIGURE 5 Bayesian inference trees of pheronematid species based on the 16S rDNA and 28S rDNA sequence data.Numbers at each node are Bayesian posterior probabilities (left) and ML analysis bootstrap values (right).