Aplysina insularis (Duchassaing & Michelotti, 1864)

Pinheiro, Ulisses Dos S., Hajdu, Eduardo & Custódio, Márcio R., 2007, Aplysina Nardo (Porifera, Verongida, Aplysinidae) from the Brazilian coast with description of eight new species, Zootaxa 1609, pp. 1-51 : 21-25

Aplysina insularis (Duchassaing & Michelotti, 1864) ( Fig. 9A , 10 , 11 A, Tab. V)

Aplysina insularis (Duchassaing & Michelotti, 1864) sensu van Soest (1978: 56); non A. insularis sensu Zea (1987) ; non A. aff. insularis sensu Collin et al. (2005) .

Aplysina fistularis forma fistularis sensu Wiedenmayer (1977, in part, specimen B877); non W. Atlantic A. fistularis of authors.

Studied material: MNRJ 4175–4176, Salvador ´s Yacht Club ( Salvador, BA, 12º59'58.2'' S - 38º31'54.2'' W), 3–5 m depth, E. Hajdu coll., 4/VII/2001. MNRJ 5463, Parcel Paredes, south side (Parque Nacional Marinho dos Abrolhos, BA, 17º56'800'' S - 38º54'264'' W), 15 m depth, E. Vilanova coll., 01/III/2002.

Comparative material: ZMAPOR. 1475, St. Thomas (Lectotype of Luffaria insularis Duchassaing & Michelotti, 1864 sensu Wiendemayer, 1977 ). BMNH 1928.5.12.75 and 172, Crawshay´s West Indian coll. (as Aplysina fistularis ). ZMAPOR 3325, Pta. Cadena (NW of Mayaguez, Puerto Rico), 3 m depth, J.H. Stock coll., 21/II/1963 (Det. R.W.M. van Soest, as Aplysina fistularis insularis ). ZMAPOR 3349, Puerto Rico (18º15' N, 67º13.5' W), 72–90 m depth, J.H. Stock coll. (# PR. 99), 27/I/1963, dredged on muddy-sand (Det. R.W.M. van Soest, as Aplysina lacunosa ). ZMAPOR 16292, 800 m of landing stage, Fort Bay ( Saba), J. Vermeulen coll., 12/III/1986 (Det. R.W.M. van Soest, as Aplysina insularis ). ZMAPOR 16303, Kralendijk Bay ( Bonaire), 2 m depth, P.L.van Pel. coll., 1965 (Det. R.W.M. van Soest, as Aplysina insularis ).

Diagnosis: This is the only Aplysina with markedly short, irregularly outlined (frequently lobate), stout, soft tubes bearing large, apical oscula. Tubes frequently wider at their apices. Colour in life yellow or brown, turning into black in ethanol.

Description of the species:

Groups of low tubes averaging 7 cm height and 2.5 cm in diameter, anastomosed, with irregular outlines (often lobate), frequently wider at their apices, where oscula 1 cm in diameter occur ( Fig. 9A ). The largest specimen is 11.5 cm long, 7 cm in maximum height and 4 cm in maximum width. Surface quite smooth alive, becoming markedly conulose upon preservation ( Fig. 10A–B ). Colour in vivo golden yellow (MNRJ 4175 and MNRJ 4176) or brown (MNRJ 5463), turning black after preservation in ethanol. Consistency is very soft.

Skeleton: Choanosome with a delicate and irregular network of spongin fibers ( Fig. 10C ). Bark with amber colour, 35–125 Μm wide (average 75 Μm). Thick pith, black or amber, 12–37 Μm wide (average 23 Μm; Fig. 10D ).

TABLE V: Spongin fibres’ measurement data for Aplysina insularis (in micrometers; S.D. = Standard Deviation and N=30).

*BA, Bahia State.

Distribution: Brazil ( Fig. 11 A): Bahia State. World: Bahamas, U.S. Virgin Islands, Puerto Rico, Saba, Bonaire.

Ecology: The specimens were collected in warm, clear waters, in depths between 3 and 12 m. The specimens from Salvador (BA) were all exposed to direct light.

Remarks: Study of A. insularis ´s lectotype (ZMAPOR 1475) convinced us of it’s unrecognizability as a consequence of its dry, macerated condition. Essential diagnostic characters recognized by us after completion of this revision are the species’ external morphology, and colour alive as well as after preservation. All these are unrecognizable in ZMAPOR 1475, apart from the likelihood that it consisted from a cluster of short tubes. At least three species described here can bear quite comparable morphologies, viz. A. fistularis , A. insularis and A. muricyana sp.n. Considering this, it appears to us advisable to request the International Commission of Zoological Nomenclature, following the steps outlined in article 75.5 of the ICZN, to set the above mentioned lectotype aside for a newly established neotype under the Commission´s plenary power. This has not been done here to avoid a further delay in the publication of this article, which has been under preparation since 2003.

The diagnosis of A. insularis by modern authors is also problematic, and care must be taken in the selection of the neotype, to make it representative of the majority of the specimens collected this far. van Soest (1978) and Zea (1987), for example, differentiated A. insularis from A. fistularis simply by the former’s short tubes against the latter’s long ones. When the plates of van Soest (1978, Plate X, Fig. 4 ) and Zea (1987, Fig.5 . p. 244), plus the BMNH and ZMA specimens analyzed here are compared, it appears that at least two species are included. We consider both BMNH specimens as well as many of the ZMA ones to belong to A. insularis as described here (ZMAPOR 3325, 6814, 16292 and 16303), but Zea’s (1987) material probably belongs to yet another species, as well as ZMAPOR 3349 (with rhizoidal processes). Zea’s (1987) “group of low tubes (2 cm in height), that leave an expanded basal mass, with a ramose stalk that penetrates the sockets of the substratum”, as well as the reported “slightly compressible” consistency (as opposed to the very soft consistency of A. insularis reported here) appear distinct from every Tropical western Atlantic species of Aplysina described to date. This material probably belong to a new species which we refrain from naming here before further study of specimens confirms their status as a new species.

Similarly, the specimen illustrated alive by Collin et al. (2005) appears distinct from every specimen of A. insularis dealt with here, as well as from those formerly assigned to A. insularis , but suggested above to be best assigned to a new species. Collin et al´s specimen misses the large apical pseudoscule and the irregularly lobate form so common in the specimens which are considered to reflect the currently ammended concept of A. insularis . For the sake of nomenclatorial stability, it is advisable to accept the many specimens assigned to A. insularis as argued above, and assign Collin et al.´s specimen to another species, possibly new, rather than the opposite.

Figures

FIGURE 4: A – C. Aplysina cauliformis (Carter, 1882). A. MNRJ 5482 (after preservation). B. Skeletal architecture (MNRJ 1137). C. Spongin fibres (MNRJ 1137). Scale bars = A. 1 cm, B. 500 µm, C. 50 µm.

FIGURE 5: A – C. Aplysina fistularis (Pallas, 1766) — in situ. A. MNRJ 4172 (Salvador, BA, Brazil). B. MNRJ 2666 (Salvador, BA, Brazil). C. Parque Nacional Marinho dos Abrolhos (BA, Brazil). Scale bar = A – B, 1 cm; C, 2 cm.

FIGURE 9: A. Aplysina insularis (Duchassaing & Michelotti, 1864: 64). B. Aplysina alcicornis sp. n. in situ, Holotype – MNRJ 5473 (Parque Nacional Marinho dos Abrolhos, BA, Brazil). C. Aplysina cristagallus sp. n. in situ, Holotype— MNRJ 3528 (Prado, BA, Brazil). Scale bar = 1 cm.

FIGURE 10: A – D. Aplysina insularis (Duchassaing & Michelotti, 1864), MNRJ 4175. A – B. habit after preservation. C. Skeletal architecture. D. Spongin fibres. Scale bars = A – B. 1 cm, C. 500 µm, D. 50 µm.

FIGURE 11: Map showing the distribution of Aplysina along the Brazilian coastline. A. Aplysina insularis (Duchassaing & Michelotti, 1864) B. Aplysina lacunosa (Pallas, 1766). C. Aplysina pergamentacea Hechtel, 1983. D. Aplysina alcicornis sp. n.. Scale bar = 500 km.