Leucetta microraphis Haeckel, 1872

Klautau, Michelle, Lopes, Matheus Vieira, Guarabyra, Bruna, Folcher, Eric, Ekins, Merrick & Debitus, Cécile, 2020, Calcareous sponges from the French Polynesia (Porifera: Calcarea), Zootaxa 4748 (2), pp. 261-295 : 281-283

Leucetta microraphis Haeckel, 1872

( Fig 9 , Table 9)

Synonyms. Dyssycus primigenius , Lipostomella primigenia , Amphoriscus primigenius , Coenostomus primigenius , Artynas primigenius , Aphroceras primigenium , Leucometra primigenia— Haeckel 1872: 118; Leucetta primigenia var. microra-phis— Haeckel 1872: 118, Ridley 1884: 482; Leucetta microraphis — Von Lendenfeld 1885: 1117 , Dendy & Row 1913: 734, Dendy & Frederick 1924: 482, Row & Hôzawa 1931: 746, Tanita 1942: 111, Burton 1963: 270, Borojević 1967: 3, Borojević & Peixinho 1976: 1003, Pulitzer-Finali 1982: 87 ( Pericharax orientalis according to Wörheide & Hooper 1999), Borojević & Klautau, 2000: 193, Wörheide & Hooper 1999: 879, Van Soest & De Voogd 2015: 54, 2018: 80; Leucandra primigenia var. microraphis— Row 1909: 186; Leucandra microraphis— Dendy 1892: 104; Leuconia dura— Poléjaeff 1883: 65, Lendenfeld 1885: 1118, Dendy 1892: 104; Leucaltis floridana var. australiensis— Carter 1886: 145; Leucandra carteri Dendy 1892: 103 ; Leucetta carteri— Dendy & Row 1913: 734, Burton 1963: 241, Borojević 1967: 5; Leucetta primigenia— Colin & Arneson 1995: 60 (photo 229); Gosliner et al. 1996: 16 (photo 4), Erhardt & Baensch 1998: 22 apud Van Soest & De Voogd 2015. The same authors mentioned that the specimens identified by Breitfuss (1896, 1898) as Leucetta solida were probably L. microraphis .

Material examined. UFRJPOR 6450 = MNHN-IP- 2018-21 — Bora Bora , Society Island (Leeward), ST SBB1 (16° 28.773’ S– 151° 41.287’ W), depth: 15 m, coll. J. Orempuller , 09/VIII/2009, P29. UFRJPOR 6452 = MNHN- IP- 2018-23 ˗ Tahiti Island (17° 32.140’ S– 149° 35.449’ W), depth: 25 m, coll. C. Debitus , 28/ V /2009, P19, ST21. UFRJPOR 6453 = MNHN-IP- 2018-24 — Tahiti , Society Islands, ST2 (17° 31.225’ S– 149° 33.220’ W), depth: 14 m, coll. C. Debitus , 24/III/2009, P8˗ST2. UFRJPOR 6457 = MNHN-IP- 2018-28 — Moorea , Society Islands, Station SM01 (17°29.681’ S– 149°51.717’ W), depth: 14 m , C. Debitus, 04/XII/2010, P8˗ SM01 . UFRJPOR 6459 = MNHN-IP- 2018-30 — Raiatea , Society Island, Station SR10 (16° 49.873’ S– 151° 20.825’ W), depth: 40 m, coll. C. Debitus , 16/VIII/2010, P64. UFRJPOR 6881 = MNHN-IP- 2018-46 — Tetiaroa , Society Islands, Station STET01 (17°02.258 S– 149°33.707 W), depth: 35 m, coll. E. Folcher , 31/ V /2011 , P348˗ STET01 . UFRJPOR 6888 = MNHN-IP- 2018-53 — Tetiaroa , Society Islands, Station STET03 (16°58.916 S– 149°34.559 W), depth: 40 m, coll. D. Fleurisson , 01/ VI /2011 , P348˗ STET03 . UFRJPOR 8961 — Tetiaroa , Society Islands, Station TTET02 (16°59.967S– 149°35.440W), depth: 28 m, coll. M. Dumas, 21/XI/2018, P678˗ TTET02 .

Colour. White to light blue or violet alive ( Fig 9A ) and beige to light brown in ethanol ( Fig 9B ).

Morphology and anatomy. This species is massive, hard and friable. It is harsh to the touch and has an amorphous shape ( Figs 9A, B ). It has several apical oscula, surrounded by membrane, and large atrium. The canals are visible through the cortex, giving an anastomosed appearance to the sponge. Aquiferous system leuconoid ( Fig 9C ). The specimen UFRJPOR 6450 has embryos.

The skeleton is composed of giant triactines present in the cortex ( Fig 9D ) and choanosome and small triactines and tetractines ( Fig 9E ). The small triactines are present in the cortex and choanosome, while the small tetractines are found only in the choanosome. The tetractines are very few and they are present only surrounding the canals.

Spicules ( Table 9)

Giant triactines. Regular (equiangular and equiradiate) and subregular (not equiradiate). Actines are conical with sharp tips ( Fig 9F ). Variable sizes. Size: 1108.3/ 137.5 µm.

Triactines. Regular to sagittal. Actines are conical with blunt tips ( Fig 9G ) but some triactines with cylindrical actines were also observed ( Fig 9I ). Size: 145.4/ 15.0 µm.

Tetractines. Regular to sagittal.Actines are conical with blunt tips ( Fig 9H ) but some tetractines have also cylindrical actines ( Fig 9J ). The apical actine is very thin, conical, sharp, and smooth ( Fig 9K ). Sometimes it is undulated Size: 136.3/ 10.4 µm (basal actine); 30.8/ 5.9 µm (apical actine).

Geographical distribution. Indo-Pacific ( Poléjaeff 1883, Ridley 1884, Von Lendenfeld 1885, Carter 1886, Dendy 1892, Row 1909, Dendy & Frederick 1924, Row & Hôzawa 1931, Colin & Arneson 1995, Gosliner et al. 1996, Erhardt & Baensch 1998, Wörheide & Hooper 1999, Borojević & Klautau 2000, Van Soest & De Voogd 2015, 2018).

Remarks. Leucetta microraphis is a widespread species with conserved skeleton but variable habitus. As these variable habitus have been considered only polymorphism (except for L. sulcata Van Soest & De Voogd, 2018 , see Discussion), we identified our specimens as L. microraphis , however, it is possible that we have a new species of Leucetta in French Polynesia. We discuss this subject in more detail at the end of the paper.

Figures

FIGURE 9. Leucetta microraphis (UFRJPOR 6450). A—Specimen in situ. B—Fixed specimen. C—Cross-section of the choanosome. D—Tangential section of the cortex. E—Tangential section of the atrium. F—Large triactines. G—Small triactines. H—Small tetractines. I—Apical actine of a tetractine. Abbreviation: at = atrium; cx = cortex.