Cyamon agnani (Boury-Esnault, 1973) Boury-Esnault, 1973

Soest, Rob van, Carballo, Jose Luis & Hooper, John, 2012, Polyaxone monaxonids: revision of raspailiid sponges with polyactine megascleres (Cyamon and Trikentrion), ZooKeys 239, pp. 1-70 : 17-21

Cyamon agnani (Boury-Esnault, 1973) comb. n. Figs 7 A–D, 8 A–F

Hymeraphia sp.; Carter 1876: 391; Higgin 1877: 296, pl. 14 fig. 9 (Grenada)

Microciona quadriradiata Carter, 1880: 42 (in part, only what was illustrated in Higgin 1877).

Trikentrion wickersi (sic); Topsent 1889: 4, fig. 2A (Campeche Bank, Gulf of Mexico); Topsent 1894: 35 (corrected to Trikentrion vickersi ).

Cyamon vickersi ; De Laubenfels 1936: 80 ( Florida ); Little 1963: 48 (Gulf of Mexico); Mothes et al. 2004: 6 (Brazil).

Cyamon vickersi var. toxifera Arndt 1927: 149, pl. 2 fig. 9, text figure 10 ( Curaçao) = mixture of Cyamon agnani and Clathria (Microciona) ferrea (de Laubenfels, 1936 as Fisherispongia ).

Cyamon toxifera ; de Laubenfels 1936: 80.

Timea agnani Boury-Esnault 1973: 276, fig. 24 (N.E. Brazil).

Not: Dictyocylindrus vickersii Bowerbank 1864; Carter 1879 = Cyamon vickersii

Nec: Microciona quadriradiata Carter 1880: 42 (in part: Gulf of Manaar specimen).

Nec: Cyamon vickersi ; De Laubenfels 1950 (Bermuda) = Timea sp.

Remark.

In view of the proposed major change in the status of Cyamon specimens reported from the Western Atlantic, description of the available material is presented in two sections, first the holotype of Cyamon agnani , subsequently other specimens known from the area and proposed to be assigned to Cyamon agnani .

Description of MNHN holotype.

Figs 7 A–D

Material examined.

HolotypeMNHN NBE 947, preserved in alcohol, Brazil, NE coast, Calypso stat. 97, 21.1667°S, 40.7°W, 12 m depth.

Description.

Small hispid crust, color ochre. Detachable skin. The material borrowed from MNHN measured a few mm2 encrusting a small piece of coral.

Skeleton: basal layer of polyactines, upon which megascleres are erected individually.

Spicules: long thin styles, short thick styles, polyactines.

Long thin styles, curved, variable in length, possibly in two size categories, but difficult to establish due to broken condition of most spicules, longest complete spicule 960 × 7 µm (Fig 7A).

Short thin styles were not mentioned in Boury-Esnault (1973), but there were a few small broken styles and one complete spicule measuring 210 × 4 µm (Fig. 7C).

Short thick styles (Fig. 7B), curved in the upper half, ending in a slight tyle, smooth, slightly variable in length and thickness, 183 –236.7– 315 × 7 –9.3– 12 µm.

Polyactines (Fig. 7D), with three to five cladi (usually four), cladi lightly spined along the shaft but with heavily spined endings, with a blunt ending in the basal cladus, and slightly inflated rounded endings in the lateral cladi. Basal cladi 32 –38.5– 48 × 3 –4.8– 7 µm, similar sized lateral cladi, 30-40 × 5 µm.

Discussion.

The Cyamon nature of this material was previously detected by Mothes et al. (2004), who examined the present type material. Their conclusion was corroborated by Van Soest (2009) in his discussion of Timea species of the West Atlantic region. Mothes et al. (2004) proposed to assign Timea agnani to the synonymy of Cyamon vickersii , but as explained above, that species differs in spiculation and geographic distribution. Despite the scanty available type material and the poor representation of short thin styles, it looks as if the categories, sizes and shapes of the spicules are broadly similar between the type of Cyamon agnani and Caribbean and Carolinian specimens recorded as Cyamon vickersii (see for details below). It is proposed here to consider all these Western Atlantic specimens as members of a widespread Cyamon agnani .

Description of ZMA material and discussion of further Western Atlantic records.

Figs 8 A–F

Material examined.

ZMA Por. 00828, holotype of Cyamon vickersii var. toxifera, preserved in alcohol, from Curaçao, Spaanse Water, on dead Porites coral, 12.076N, 68.858W, coll. C.J. van der Horst, field number 65a, 19 –05– 1920.

ZMA Por. 10539, preserved in alcohol, Colombia, Santa Marta region, El Morro, 15 m, 11.25N, 74.2167W, coll. B. de Jongh, 26 –10– 1989 (Fig. 1A2).

USNM 22456, preserved in alcohol, Florida, SE of Loggerhead Key, on a block of limestone dredged from 70 m, coll. M.W. de Laubenfels, 26 June 1932.

USNM 221078 (23563), preserved in alcohol, Florida, Northern Gulf of Mexico, Apalachee Bay, rock and sand, 29.785 - 29.8°N, 84.325°W, 11 m, coll. F. Little, 1956-57;

USNM 33518, preserved in alcohol, off South Carolina, RV Oregon (S.C. Mar. Res. BLM), stat. 0SO6, 32.4883°N, 78.8217°W, 48 m, collected by grab, 4 May 1981.

Description.

(Based on ZMA Por. 10539). Irregular encrustation (Fig. 8A1), with hispid, bumpy surface (preserved condition). Size 3 × 2.5 cm in lateral expansion, 3-5 mm in thickness. Colour (alive) red, (alcohol) red-brown. Consistency soft.

Skeleton (Fig. 8A2): basal mass of polyactine spicules penetrated by single short thick styles erect with heads embedded in the substrate. Long thin styles also erect on the substrate with rare short thin styles arranged around the peripheral protruding apices. This ‘raspailid’ feature was only observed in a few places.

Spicules: long thin styles, short thin styles, short thick styles, polyactines.

Long thin styles (Figs 8B, B1), complete ones with a wavy outline (Fig. 8B), but mostly broken in the slides, largest complete style 2065 × 9 µm, with smaller pieces varying down to 1170 × 7 µm.

Short thin styles, straight (Fig. 8C), 423 –486.6– 658 × 2 –2.2– 2.5 µm. We were unable to find a complete spicule on the SEM stub, so we only show a broken spicule in Fig. 8C.

Short thick styles, (Figs. 8D, D1) curved in the upper half, with a faint tyle, smooth, in a large size range, 174 –358.2– 489 × 9 –14.4– 21 µm.

Polyactines (Figs 8 E–F), with three to five cladi (usually four), typically with all cladi mostly smooth but ending in a spined apex, the basal cladus usually bluntly pointed, the lateral cladi with inflated endings (Fig. 8E), early growth stages smooth and with all cladi pointed (Fig. 8F), cladi often of unequal length but without clear pattern of variation, basal cladi 39 –56.4– 66 × 6.5 –8.3– 10 µm, either longer or shorter than the lateral cladi, 36 –61.6– 87 × 4.5 –7.6– 10 µm.

Distribution.

Greater Caribbean, Gulf of Mexico, South Carolina, N.E. Brazil.

Ecology.

Encrusting dead corals and other limestone substrates, 0-70 m.

Discussion.

Topsent (1889) records thinly encrusting specimens of the species under the name Trikentrion wickersi . This was apparently a common species on the Campeche Bank in the Mexican part of the Gulf of Mexico. His specimens were violet or blackish brown in color (preserved) and he observed that next to four-claded spicules also five-claded and three-claded occurred, though rarely. His drawings of the polyactines conform closely to those of our material, but no spicule sizes were given. Topsent (l.c.) believed that the similarities between Cyamon and Trikentrion were too great to keep them as separate genera, but his choice of Trikentrion as the valid name for the group is incorrect as Cyamon is the older name.

De Laubenfels (1936: 80) recorded the species from Florida from a depth of 70 m as a bright orange crust with lateral expansion of 7 cm2 and thickness of 1 mm. This specimen, USNM 22456, which was received on loan from the Smithsonian Insitution, showed long thin styles up to 2 mm (one complete spicule measured 1939 × 9 µm); short, straight, thin styles 270-590 × 1.5-3 µm (not mentioned by De Laubenfels); short thick styles 420-602 × 27-32 µm (also not mentioned by De Laubenfels); polyactine spicules (three-, four- and five-claded) with basal cladi 51-63 × 9-14 µm and lateral cladi 39-51 µm.

De Laubenfels (1950: 68, fig. 30) also reported the species from Bermuda (as Cyamon vickersi ), depth not given. The specimen was probably not a Cyamon , because the drawings of the polyactine spicules appear to be rather those of a Timea aster with proliferated rays. The Bermuda occurrence must thus be considered suspect.

Little (1963) recorded Cyamon vickersii as an orange encrustation from the Gulf of Mexico, depth 11 m. His description is obviously copied from De Laubenfels (1936), as he gives exactly the same measurements of the spicules and also omitted to mention the short thick styles. We were able to examine this specimen, USNM 221078, thanks to a loan from the Smithsonian Institution. It has long thin styles 1050-1563 × 9 µm, short thin styles 330-345 × 2-3 µm, short thick styles 270-332 × 13-20 µm, polyactines (three-, four-, and five-claded) with basal cladi 36-60 × 7-12 µm and lateral cladi 33-61 × 7-10 µm.

The loan from the Smithsonian also included an undescribed specimen from South Carolina, USNM 33518. This had long thin styles of up to 2 mm, short thin styles 360-426 × 2-2.5 µm, short thick styles 410-500 × 22-23 µm, and polyactines (three- and four-claded) with basal cladi 48-93 × 12-15 µm and lateral cladi 45-49 × 12-14 µm.

Alcolado (1994) in an unpublished list of Cuban sponges lists Cyamon vickersii from Cuban waters, which presumably concerns also the species we here propose to call Cyamon agnani .

We investigated the type material of Cyamon vickersii var. toxifera Arndt, 1927 (the name should be corrected to toxiferum to match the gender of the genus), ZMA Por. 00828, from Spaanse Water, Curaçao, and discovered that the toxas forming the basis of Arndt’s variety are clearly foreign. They form part of the spiculation of a microcionid sponge, readily identified as Clathria (Microciona) ferrea (De Laubenfels, 1936 as Fisherispongia ) by its characteristic polytylote subtylostyles (see also description of Curaçao material of that species in Van Soest 1984). This discovery means that the name Cyamon (Microciona) ferrea is threatened by Arndt’s variety. The material is so scanty, that any trace of Cyamon polyactines has now (2012) disappeared from the sample. De Laubenfels (1936: 80) elevated Arndt’s variety to specific rank; needless to say that this is unwarranted.

The spicule complement and the shape of the polyactines is broadly similar in the Brazilian type of Cyamon agnani and specimens recorded from Caribbean and Carolinean waters as Cyamon vickersii , but the latter may have long thin styles up to twice as long. The short thick styles and the polyactines also are on average clearly longer and more robust in Caribbean specimens. The geographic separation caused by the Amazonian outflow could be a barrier to gene flow between these shallow-water sponges, and the differences may thus have a genetic background. On the other hand, the Brazilian type material is only a single small specimen and variation in Brazilian waters may turn out to be as large as that in the Caribbean. Thus distribution and ecology for this species may be summarized as: tropical waters of Brazil, the Greater Caribbean and Gulf of Mexico, South Carolina, known from 0-70 m depth, usually encrusting dead corals and other limestone substrates.