Antarctotetilla pilosa, Carella & Uriz, 2018

Carella, Mirco & Uriz, Maria J., 2018, Description of two new genera (Antarctotetilla, Levantiniella) and a new species of Tetillidae, Zootaxa 4455 (2), pp. 295-321 : 311-313

publication ID	https://doi.org/ 10.11646/zootaxa.4455.2.3
publication LSID	lsid:zoobank.org:pub:B8FBCB01-CA87-4761-A9F9-2D90AB9EF597
DOI	https://doi.org/10.5281/zenodo.5988737
persistent identifier	https://treatment.plazi.org/id/A005C267-410A-BA2E-FF68-C5344A3D4D13
treatment provided by	Plazi
scientific name	Antarctotetilla pilosa
status	sp. nov.

Treatment

Antarctotetilla pilosa View in CoL nov. sp.

Material examined: 1 individual (holotype, CEAB. POR. BIO.502a ANT 27211), South Orkneys , Subantarctic region, - 61° 8.74‘S, -43° 58.15‘W, 407 m depth, 19 February 2011 ( Carella et al. 2016).

GenBank accession numbers ( Carella et al. 2016): CEAB.POR.BIO.502a ANT 27211( KT124313 View Materials see S1, KT124355 View Materials and KT124361 View Materials ).

Description ( Fig. 12 View FIGURE 12 ). Globular, 8 cm in diameter sponge ( Fig. 12a, b and c View FIGURE 12 ).Long hairy hispidation protruding up to 2 cm, throughout the surface, caused by long fusiform oxeas, protriaenes, and sometimes anatriaenes. This hispidation becomes much longer (up to 4 cm) after sponge desiccation due to flesh retraction. Oscules of several sizes spread on the sponge body ( Fig. 12d View FIGURE 12 ). Pores grouped in more or less deep surface depressions ( Fig. 12e View FIGURE 12 ). Pseudocortex ( Fig. 12f View FIGURE 12 ) composed of loose auxiliary oxeas perpendicular to the sponge surface. Megascleres: oxeas, protriaenes, anatriaenes, and trichodal protriaenes; microscleres: sigmaspires. A basal root-tuft system of anatriaenes.

Spicules ( Fig. 13 View FIGURE 13 ; Table 1). Megascleres: oxeas I ( Fig. 13a View FIGURE 13 ) large and fusiform: 4050–7682.5–10950 µm x 35 – 83.5–120 µm. Auxiliary small oxeas II ( Fig. 13b View FIGURE 13 ): 630– 1137–1780 µm x 12.5–22.4–35 µm. Anatriaenes I ( Fig. 13f View FIGURE 13 ): 7180–12460–16880 µm x 22.5–24.5–27.5 µm in size with long and thin clades: 160–190.5–210 µm long; rhabdomes fusiform, thicker at the middle and filiform at the terminal part. Anatriaenes II: 3220–3806.7–4960 µm x 15 –17.5–22.5 µm in size ( Fig. 13e View FIGURE 13 ) with short clades: 62.5–85.8–130 µm and fusiform rhabdomes. Anatriaenes III ( Fig. 13g View FIGURE 13 ): 4400–10265–14350 x 17.5–24.4–27.5 µm in size with thick, 70–117.6 –140 µm long clades; rhabdomes fusiform, thicker at middle and filiform at the terminal part. Protriaenes I ( Fig. 13d View FIGURE 13 ): 4300–6986.2– 10880 µm x 20–30–40 µm with clades: 100–181.7–260 µm long, usually one clade longer than the other two; rhabdomes tapering from the base of the clades to end in a filamentous termination. Protriaenes II ( Fig. 13c View FIGURE 13 ): 2400– 2767.5–3250 µm x 10 –11.9–17.5 µm, with clades: 80–142–240 µm in length, usually one clade longer than the other two; rhabdomes tapering to a filiform end. Trichodal protriaenes ( Fig. 13h View FIGURE 13 ) very small with filamentous rhabdomes: 405–1063.6–2480 µm x 2 –2.6–5 µm long and thin, 10–51.4–175 µm long clades. Microscleres: sigmaspires ( Fig. 13i View FIGURE 13 ): 10–11.6–12.5 µm in length.

Skeletal arrangement. Choanosomal skeleton composed by bundles of oxeas protriaenes and anatriaenes spirally arranged from the central part toward the periphery. Auxiliary oxeas either disposed in palisade at the sponge periphery or scattered in the choanosomal zone. Trichodal protriaenes distributed at the peripheral zone; sigmaspires spread through the sponge. Anatrianes III form part of the dense hair-like surface tufts.

Distribution and habitat. The only individual available was collected from the Subantarctic (South Orkneys) at a depth of 407 meters.

Remarks. Morphologically, this species fits within Antarctotetilla as it has their pores grouped in surface depressions and a pseudocortex. Antarctotetilla pilosa differs from other species of the genus by the presence of a hair-like hispidation through the whole sponge, and a third type of anatriaene with short and thick clades (anatriaene III).