Haliclona (Gellius) loe, Vicente & Rutkowski & Lavrov & Martineau & Timmers & Toonen, 2025

Haliclona (Gellius) loe sp. nov. ( Fig. 2–3 View FIGURE 2 View FIGURE 3 , Table 1 View TABLE 1 )

LSIDurn:lsid:zoobank.org:act: 07053669-D76E-437D-8628-C4B7DDFCB540

Haliclona sp. JV 11 in Vicente et al., 2022a, 2022b

Holotype and type locality. BPBM C1523 About BPBM -Mammal pens at Moku o Loʻe (Coconut Island), Kāne‘ohe Bay, Oʻahu, (21.4324 °N, - 157.7908 °W); 0.5 m, coll. Jan Vicente, 2016-12-16 GoogleMaps . Paratypes. BPBM C1549 About BPBM GoogleMaps , BPBM C1533 About BPBM ; ARMS in mesocosms at the Hawai‘i Institute of Marine Biology ( HIMB) in Moku o Loʻe ( Coconut Island ), Kāne‘ohe Bay , Oʻahu, (21.4335 °N, - 157.7864 °W); 0.3 m coll. Jan Vicente, 2018-03-16, 2018-03-16, and 2018-06-11 respectively GoogleMaps . BPBP C1534 - Keʻehi harbor , Oʻahu (21.3208 °N, - 157.8940 °W); 2 m, coll. Jan Vicente, 2018-5-15 GoogleMaps . BPBM C1673 About BPBM - Kewalo Marina , Oʻahu (21.2937 °N, - 157.8566 °W); 3 m, coll. Jan Vicente, 2018-5-25 GoogleMaps . BPBM C1672 About BPBM - Pūpūkea Marine Life Conservation District , Oʻahu (21.6534, -158.0626); 10 m, coll. Jan Vicente, 2022-09-03. GoogleMaps Additional information from other vouchers can be found in Table S1 View TABLE 1 .

Diagnosis. A thickly encrusting or cushion shaped Haliclona (Gellius) , with light yellow, bright yellow, brownish pink exterior and interior, uneven punctate surface, firm but crumbly consistency, undefined ectosome but with a unispicular to paucispicular confused choanosomal skeleton that becomes more unispicular and isodictyal closer to the surface, spicules are oxeas (138–253 x 1– 9 µm) and small sigmas (7–12.0 x 0.3–1.1 µm).

Description ( Fig. 2 View FIGURE 2 ): Thick (1–2 cm) cushion-shaped encrustation that spreads laterally (16 cm). Surface can be hispid, uneven, bumpy and punctate. Oscula are volcano shaped measuring between 2–6 mm in diameter and rise 0.5 cm from the base of the sponge surface. Consistency is firm but crumbly and breaks easily when compressed. Color in life of the sponge surface varies between light brownish pink in small recruits to faint yellow and bright yellow in larger specimens, sponge interior is brownish pink. Exudes dark brown pigments when preserved in ethanol and the remaining color of the specimen is grey. Embryos measuring 500 µm in diameter were abundant in the choanosome of the holotype BPBM C1523 ( Fig. 2b View FIGURE 2 ).

Skeleton ( Fig. 3a–e View FIGURE 3 ): Ectosome is not specialized. The choanosome is confused, isotropic, consisting of unispicular to paucispicular (1–2 spicule thick) lines occasionally in isodictyal reticulation but also halichondroid. Reticulation is more confused deep in the choanosome and becomes somewhat anisotropic closer to the ectosome. At the surface, more organized, unispicular to paucispicular lines are connected irregularly by unispicular secondary lines which occasionally break the surface by a single oxea (100–140 µm from the surface). 4–10 spicules meet at the nodes forming triangular (90–100 µm in diameter), pentagonal, and hexagonal meshes (up to 240 µm in diameter). A network of canals (cavernous system) is observed in the choanosome. Spongin is present at the nodes and throughout the skeleton giving the choanosome a light brown pigmentation.

Spicules ( Fig. 3 View FIGURE 3 f-h; Table 1 View TABLE 1 ): Oxeas straight and curved at the center with acerate tips 138–179–253 x 1–5– 9 µm ( Fig. 3f–g View FIGURE 3 ). Oxeas with blunt tips are rare. Sigmas are C-shaped, very abundant throughout the sponge tissue, and are in a single size category 8.7–9.9–12.0 x 0.3–0.6–1.1 µm ( Fig. 2h View FIGURE 2 ).

Habitat and ecology. Specimens were collected inside lava tubes on Oahu’s North shore, on shaded pilings in Keʻehi Harbor on the south shore, and on nets that used to confine mammals at HIMB. Specimens were also collected inside mesocosm ARMS. Absence of these species on reef ARMS, where the surrounding sponge community is at a climax stage of succession, suggests that Haliclona (Gellius) loe sp. nov. is an early colonizer during pioneering stages of ecological succession (Sup. Fig. S 3 View FIGURE 3 in Vicente et al., 2022a). Presence of embryos within the holotype indicates viviparous reproduction.

Distribution ( Fig. 1 View FIGURE 1 ). Moku o Loʻe (Coconut Island), Kāne‘ohe Bay and Keʻehi harbor on the island of Oʻahu, Hawaiʻi.

Etymology. The given name honors the moʻolelo (historical accounts from native Hawaiians) of how Moku O Loʻe was named. Lo‘e was the sister of three brothers who kept honesty within the family. We use the feminine loe following the feminine gender of Haliclona and Article 31.2 of the International Code for Zoological Nomenclature (http://www.iczn.org/, accessed on October 16, 2023).

Taxonomic remarks. Variability of the skeleton morphology in Haliclona (Gellius) loe between unispicular to paucispicular or from halichondroid, isodictyal, to anisotropic at the sponge surface matches the definitions for either, H. ( Gellius ), H. ( Halichoclona ) or H. (Soestella) ( de Weerdt, 2002). All replicates of H. (Gellius) loe lack a specialized ectosome as well as the presence of subectosomal or choanosomal spaces which are characteristic of H. ( Halichoclona ). Likewise, paucispicular lines do not form circular meshes anywhere throughout the choanosome or ectosome, which is diagnostic of H. (Soestella). The closest fitting definition remaining considering all characters of the new species including the presence of sigmas as microscleres is that of H. ( Gellius ).

The spicule composition of 80% of H. ( Gellius ) spp. (61 species) consist of sigmas and oxeas. Haliclona (Gellius) loe stands out from most of these species by the smaller length of sigmas (8.7–11.5 µm in length). The only species having sigma dimensions similar to Haliclona (Gellius) loe sp. nov. are Haliclona (Gellius) amboinensis ( Lévi 1961) (9–17 µm in length), Haliclona (Gellius) microsigma ( Babic 1922) (8–10 µm in length) and Haliclona (Gellius) patbergquistae van Soest et al. 2020 (11–14 µm in length) ( Table S2 View TABLE 2 ). These species are set apart from H. ( Gellius ) lo e by their larger sized oxeas ( H. (Gellius) microsigma (200–240 x 5–10 µm), H. (Gellius) patbergquistae (305–343 x 12 μm), H. (Gellius) amboinensis (175–230 x 7–14 μm)). Other matching H. ( Gellius ) spp. possibilities possibilities with small sigmas are Haliclona (Gellius) concreta Bispo et al., 2022 (5–8 µm in length), Haliclona (Gellius) dubia ( Babic, 1922) (12–16 µm in length), Haliclona (Gellius) rava ( Stephens 1912) (8 µm in length), Haliclona (Gellius) regia ( Brøndsted 1924) (10–18 µm in length), Haliclona (Gellius) tenerrima (6–10 µm in length) Burton 1954. However, these small-sigma-bearing sponges are distinguishable from the new species in that they all have toxas in their spicule composition. Among sigma bearing Haliclona spp. of unknown subgenera are Haliclona aperta ( Sara 1960) (34–43 µm in length) from the Mediterranean, Haliclona libera (15 μm in length) and Haliclona uwaensis ( Hoshino 1981) (10–22 µm in length) from Japan, and Haliclona sabulosa Bergquist & Warne 1980 (34–43 µm in length) from New Zealand. All can be discarded as possible matches by the size of their sigmas which exceeds the length of sigmas of the new species.