Haliclona (Flagellia) hentscheli, Van Soest, 2017

Van Soest, Rob W. M., 2017, Flagellia, a new subgenus of Haliclona (Porifera, Haplosclerida), European Journal of Taxonomy 351, pp. 1-48 : 17-19

Haliclona (Flagellia) hentscheli subgen. et nom. nov.

Fig. 9

Gellius incrustans Hentschel 1912: 390 , pl. XV fig. 3, pl. XXI fig. 45.

Etymology

The specific epithet refers to E. Hentschel, author of Gellius incrustans .

Material examined

INDONESIA: South Sulawesi, Tana Djampea, Kambarangi Bay, 7.1058° S, 120.6274° E, depth 0–32 m, trawl, coll. Siboga Expedition stat. 64, 4 May 1899 ( ZMA Por. 01225), same data as for previous ( ZMA Por. 01226); Maluku,Ambon,Ambon Bay, near Hative Besar, 3.6833° N, 128.1333° E, 0–5 m, snorkeling, coll. R.W.M. Van Soest, Snellius II Expedition stat. 002/II/18A, 6 Sep. 1984 ( ZMA Por. 08797); Snellius II Expedition, fieldnr 4.045, NE coast of Sumba, E of Melolo, 9.9033° S, 120.7167° E, depth 48–57 m, Van Veen grab, 13 Sep. 1984 (unregistered slide); Snellius II Expedition, fieldnr 56J, NE coast of Sumba, E of Melolo, 9.9° S, 120.7477° E, depth 125 m, dredge, 14 Sep. 1984 (unregistered slide).

Description

Encrusting sponges with an uneven surface ( Fig. 9A ), with slightly raised oscules ( Fig. 9A 1 ). One (ZMA 01225, Fig. 9A ) encrusts the base of an octocoral. Greyish beige in alcohol. Lateral size up to 2 × 1 cm, thickness 3–4 mm, oscules 2 mm in diameter. Consistency soft.

SKELETON. Confusedly Haliclona -like, with paucispicular primary tracts interconnected by single oxeas. Special surface reticulation lacking. No visible spongin.

OXEAS ( Fig. 9 B–B1). Sharply pointed, straight, in a narrow size range, 198– 214 –238 × 4– 6. 4 –11.5 μm.

FLAGELLOSIGMAS ( Fig. 9 C–E). Circular to ovoid in shape, in two size categories. Larger ones ( Fig. 9 C– D) with rather short but distinctly upturned long endings ( Fig. 9C 1 ), both large and small ones with gradually widely curved short endings ( Fig. 9C 2 , E). Large flagellosigmas (I), with length of long endings 69– 84 –98 μm, short endings 51– 54 –63 μm, widths 53– 66 –83 μm, thickness 1.5– 1. 7 –2 μm. Small flagellosigmas (II) ( Fig. 9 E–F), with length of long endings 27– 42 –66 μm, short endings 16– 24 – 34 μm, widths 18– 29 –39 μm, thickness 0.5– 0. 8 –1.5 μm.

NORMAL SIGMAS ( Fig. 9 G–H). The most common microscleres, occurring in two distinct size classes, the larger ones (I) ( Fig. 9G ) with rather sharply bent endings, robust, 57– 71 –81 × 1.5– 2. 4 –3 μm, the smaller thinner ones (II) ( Fig. 9H ) incurved more roundedly, 14– 22 –32 × 0.5– 0. 6 –1 μm.

Distribution and ecology

Indonesia: Aru Islands, Tana Djampea (island south of Sulawesi), Ambon, Sumba (Marine Ecoregions Arafura Sea, Banda Sea, Lesser Sunda), coral reefs and sand bottoms at 12–125 m depth.

Remarks

The specimens described here are judged to be conspecific with Gellius incrustans Hentschel, 1912 . However, data provided by Hentschel do not entirely match the present specimens: normal sigmas are described as very common, but no size categories were mentioned; only the largest size is quoted as 43– 56 μm, smaller than the present 57–81 μm. Flagellosigmas are quoted as having a largest ‘Durchmesser’ of 47–51 μm, likewise smaller than in the present specimens. Oxeas were 156–180 × 5–6 μm, according to Hentschel. It remains to be established whether the differences observed here are the result of a less than optimal description by Hentschel, or a genuine difference, in which case the present specimens belong to an undescribed species.

Apart from these differences, transferring Gellius incrustans to the combination Haliclona (Flagellia) incrustans , created a junior secondary homonym of Haliclona foraminosa incrustans ( Czerniavsky, 1880) (originally Protoschmidtia foraminosa forma incrustans ) and of Haliclona simulans incrustans ( Carter, 1887) ( Carter 1887: 70, originally Isodictya simulans var. incrustans ). Burton (1959b: 220) already solved the latter case of homonymy by giving Carter’s subspecies the new name Haliclona carteri Burton, 1959 . Here the new combination Haliclona (Flagellia) hentscheli nom. nov. is proposed to solve the homonymy with Czerniavsky’s (1880) species, which, in spite of its unrecognizable description remains a senior secondary homonym until such time as its status is resolved. Future reallocation of these species to other valid genera will require reinstatement of Hentschel’s and Carter’s names.

Burton’s (1928) deep-water record of Gellius flagellifer from the nearby Andaman Sea was possibly the present species, as the upper size of the normal sigmas falls within the variation of the above measurements. However, the oxeas of the Andaman specimens are 280–360 × 12–14 μm, well in excess of those measured above. Combined with the deepwater occurrence (300–900 m) the conspecificity appears doubtful.

Figures

Fig. 9. Haliclona (Flagellia) hentscheli subgen. et nom. nov. A. Habitus of ZMA Por. 01225 from Tana Djampea, Kambarangi Bay, Indonesia (scale bar = 1 cm). A 1. Habitus of ZMA Por. 01226, from same locality (scale bar = 1 cm). B–H. SEM images of spicules (ZMA Por. 01225). B. Oxeas. B 1. Detail of one of the apices. C–D. Large category (I) of flagellosigmas. C 1. Detail of long ending of large flagellosigma. C 2. Detail of short ending of large flagellosigma. E–F. Small flagellosigmas (II). G. Large sigma category (I). H. Small sigma category (II).

Fig. 1. Flagellosigma, the characteristic feature of Haliclona (Flagellia) subgen. nov., showing meristic and descriptive features used in this study.

Fig. 2. ‘Flagellated’ sigma of Mycale (Naviculina) diversisigmata Van Soest, 1984, a sigma type superficially similar to a flagellosigma, but the morphology is considered non-homologous due to the lack of a strong asymmetry in the longer and shorter endings.