INTRODUCTION
Some marine invertebrates, including most shallow-water scleractinian corals, have a symbiotic relationship with photosynthetic dinoflagellates (Boschma, Reference Boschma1925; Fitt et al., Reference Fitt, Spero, Halas, White and Porter1993; Trench, Reference Trench1997; Costa et al., Reference Costa, Sassi and Lira2008) and, consequently, are restricted to shallow-waters. However, almost half of the extant scleractinians do not present this symbiosis (Cairns, Reference Cairns2007) and are able to inhabit aphotic zones and live heterotrophically (Kitahara, Reference Kitahara2006; Roberts et al., Reference Roberts, Wheeler, Freiwald and Cairns2009). Therefore, with no taxonomic validity, scleractinian corals can be grouped on the presence or absence of these symbionts, and are commonly referred to as zooxanthellate or azooxanthellate corals, respectively (Cairns, Reference Cairns1977; Schuhmacher & Zibrowius, Reference Schuhmacher and Zibrowius1985; Capítoli & Bemvenuti, Reference Capítoli and Bemvenuti2004; Cairns et al., Reference Cairns, Häussermann and Försterra2005; Cairns, Reference Cairns2007).
To date, the number of azooxanthellate scleractinians from Brazil has a 4:1 ratio in relation to the number of zooxanthellate species (Pires, Reference Pires, George and Cairns2007). Due to their ecological constraints and following a worldwide tendency, the distributional records of both groups in Brazilian waters show a much broader latitudinal/depth range for azooxanthellate species than that of zooxanthellate corals. Most of our knowledge about the Brazilian azooxanthellate coral fauna was acquired during or with the specimens collected through oceanographic expeditions carried out in the 18th Century (Pires, Reference Pires, George and Cairns2007; Kitahara, Reference Kitahara2009). However, some regions with potentially diverse azooxanthellate coral fauna are still poorly sampled, especially those from the north-eastern and northern Brazilian coast.
Despite the scarce scientific campaigns aspiring to collect deep-water organisms in Brazil, 63 scleractinian species are reported for the Brazilian Exclusive Economic Zone (EEZ) (Cairns, Reference Cairns1979, Reference Cairns2000; Kitahara, Reference Kitahara2007; Pires, Reference Pires, George and Cairns2007; Neves & Johnsson, Reference Neves and Johnsson2009). However, due to the low sampling efforts related to the scarce financial and logistical investments (Lindner & Kitahara, Reference Lindner and Kitahara2007), it is believed that the species richness of azooxanthellate scleractinians from the Brazilian EEZ is still underestimated (see Kitahara, Reference Kitahara2007). Aiming to contribute to the knowledge about azooxanthellate scleractinians from Brazil, the present study reports the first occurrence of Polycyathus senegalensis Chevalier, Reference Chevalier1966 and Eguchipsammia cornucopia (Pourtalès, Reference Pourtalès1871), and expands the latitudinal and/or bathymetric ranges of the other nine species previously reported from this region.
MATERIALS AND METHODS
The specimens examined herein were collected by SCUBA diving or by bottom trawling throughout the Brazilian coast (Figure 1; Table 1). Vouchers were deposited at the scientific collections of the Reef Environment Laboratory of the Federal Rural University of Pernambuco (LAR/UFRPE); National Museum/Federal University of Rio de Janeiro (MNRJ); and/or Oceanographic Museum of the Pernambuco Federal University (MOUFPE).
Fig. 1. Map of the collection stations in Brazil.
Table 1. List of collection stations.
Morphometrics and meristics followed Vaughan & Wells (Reference Vaughan and Wells1943), Wells (Reference Wells1972), Cairns (Reference Cairns2000) and Kitahara (Reference Kitahara2007).
Abbreviations
Morphological terms: GCD, greater calicular diameter; LCD, lesser calicular diameter; PD, pedicel diameter. Locations: ASPSP: St Peter and St Paul Archipelago (00°55′N 29°20′W); FN, Fernando de Noronha (03°55′S 32°38′W).
RESULTS
SYSTEMATICS
Fig. 2. (A, B) Polycyathus senegalensis: (A) colony view (MNRJ 8189); (B) calicular view (LAR/UFRPE 399). (c–e) Eguchipsammia cornucopia: (C) lateral view (LAR/UFRPE 650); (D) (juvenile); (E) (adult) calicular views (MNRJ 8190). Scale bar = 10 mm.
Polycyathus senegalensis Chevalier, Reference Chevalier1966: 971–974, Pl. 4, figures 7–8. Best, Reference Best1968: 72. Patriti, Reference Patriti1970: 83–84. Zibrowius, Reference Zibrowius1980: 94. Hubbard & Wells, Reference Hubbard and Wells1986: 133–134, figures 21–22. Verheij & Best, Reference Verheij and Best1987: 153. Cairns et al., Reference Cairns, Opresko, Hopkins and Schroeder1994: 7. Cairns, Reference Cairns2000: 83–86, figures 17 & 92–95. Reyes et al., Reference Reyes, Santodomingo and Flórez2010: 95, three figures.
Polycyathus mullerae: Hubbard & Wells, Reference Hubbard and Wells1986: 134, figures 23–24. (Not Polycyathus muellerae (Abel, 1959).)
Paracyathus pulchellus: Cairns, Reference Cairns1979: 88–90, Pl. 16, figure 5 (in part). Hubbard & Wells, Reference Hubbard and Wells1986. (Not Cyathina pulchellus Philippi, 1842.)
Polycyathus sp.: Edwards & Lubbock, Reference Edwards and Lubbock1983a: 62. Amaral et al., Reference Amaral, Hudson, Silveira, Migotto, Pinto and Longo2002: 569. Amaral et al., Reference Amaral, Silveira, Vasconcelos, Ramos, Vaske Júnior, Lessa, Nóbrega, Amaral and Silveira2006: 72, figure 6.4.
TYPE LOCALITY
Dakar Region (Senegal), depth unknown.
MATERIAL EXAMINED
LAR/UFRPE 399 (ASPSP), 18 m (2 colonies); LAR/UFRPE 401 (ASPSP), 30 m (1 colony); MNRJ 8189 (ASPSP), 20 m (1 colony); MNRJ 8191 (ASPSP), 19 m (1 colony).
DIAGNOSIS
Colonies phaceloid and firmly attached to substrate. Coenosteum conspicuous, smooth (sparsely granulated), thick and continuous. Collected colonies have an average of five corallites per cm2. Intercorallite distance between 1 and 4 mm. Corallite cylindrical and up to 20 mm in height. Calice slightly elliptical (up to 10 mm in GCD). Septotheca costate. Costae extend from calice to half distance to pedicel. Septa hexamerally arranged in four complete cycles (6S1 > 6S2 > 24S4 ≥ 12S3). S5 sometimes present. S1 most exserted (0.5 to 1.5 mm) and largest septa. S2 about 2/3 width and only slightly less exsert than S1. S3 least developed septa. Pairs of S4 fused to adjacent S1–2 near calicular edge forming small rectangular lancets. Pali present in two crowns before all but last cycle (P3 > P1–2). P3 bilobate or trilobate. Columella papillose (0.8 to 2.5 mm in diameter) consisting of 6 (young corallites) to 16 small elements.
REMARKS
In Brazilian waters, the genus Polycyathus has been previously reported from St Peter and St Paul Archipelago (Edwards & Lubbock, Reference Edwards and Lubbock1983b; Amaral et al., Reference Amaral, Hudson, Silveira, Migotto, Pinto and Longo2002; Reference Amaral, Silveira, Vasconcelos, Ramos, Vaske Júnior, Lessa, Nóbrega, Amaral and Silveira2006). However, the specimens examined are the first identified to species level, and therefore, represent the first record of P. senegalensis for Brazil.
Among azooxanthellate scleractinians reported from Brazil, P. senegalensis is most similar to Paracyathus pulchellus (Philippi, 1842). However, it is distinguished by forming true colonies (Cairns, Reference Cairns2000). The well-developed coenesteum and/or stoloniferous connection between corallites differentiate P. senegalensis from rhizangids reported from Brazil like Astrangia solitaria (Lesueur, 1817) (Cairns, Reference Cairns2000).
DISTRIBUTION
Western Atlantic: Gulf of Paria; from Venezuela to French Guiana; Cape Canaveral, FL; off James Island, SC/GA; Cape Lookout, NC (Cairns, Reference Cairns2000); Brazil, ASPSP (Present study). Eastern Atlantic: Senegal and Morocco (Cairns, Reference Cairns1999a; Reference Cairns2000). Bathymetric range: 12 to 150 m (Edwards & Lubbock, Reference Edwards and Lubbock1983b; Reyes, Reference Reyes2000; Reyes et al., Reference Reyes, Santodomingo and Flórez2010).
Dendrophyllia cornucopia Pourtalès, Reference Pourtalès1871: 45, Pl. 5, figures 7 & 8. Cairns, Reference Cairns1978: 11, Table 1. Cairns, Reference Cairns1979: 179–181, Pl. 36, figures 1–4, Map 54. Zibrowius, Reference Zibrowius1980: 175–176, pl. 88, figures A–L. Not Hubbard & Wells, Reference Hubbard and Wells1986: 139, figures 33–35 (Rhizopsammia goesi). Viada & Cairns, Reference Viada and Cairns1987: 32. Cairns & Wells, Reference Cairns and Wells1987: 43, Pl. 11, figures 14–17. Cairns, Reference Cairns1999b: Table 1.
Balanophyllia [sic] cornucopia. Cairns et al., Reference Cairns, Opresko, Hopkins and Schroeder1994: 5.
Eguchipsammia cornucopia. Cairns, Reference Cairns1994: 85. Cairns, Reference Cairns2000: 169–170, figure 198. Reveillaud et al., Reference Reveillaud, Freiwald, Rooij, Guilloux, Altuna, Foubert, Vanreusel, Roy and Henriet2008: 322. Reyes et al., Reference Reyes, Santodomingo and Flórez2010: 120.
TYPE LOCALITY
Off Key West, Florida, 220–229 m.
MATERIAL EXAMINED
MNRJ 8190, 03°54,9′00″S 32°37,8′00″W (FN), 380 m (5 specimens); LAR/UFRPE 876, 03°54,9′00″S 32°37,8′00″W (FN), 380 m (40 specimens). All collected by RV ‘Natureza'.
DIAGNOSIS
Corallum cylindrical to vermiform, and free. Calice elliptical. Largest specimen examined (MNRJ 8190) 14.6 mm in calicular diameter, 4.2 mm in PD, and 113.0 mm in height. Theca porous bearing up to 27 asexual buds or bud scars. Epitheca present on lower part of corallum. Costae flat, marked by conspicuous striae (larger in young specimens). Septa hexamerally arranged in five incomplete cycles. Larger specimens display up to 66 septa. S1 is the only independent septa. Septal margins often beaded, and those of S4 laciniate. Pali absent. Fossa shallow, containing a well-developed, elliptical, and convex columella.
REMARKS
According to Cairns (Reference Cairns2000), E. cornucopia reproduces asexually through thecal buds. However, some specimens examined herein (also mentioned in specimens from the Caribbean (Cairns, Reference Cairns2000)), have settled on skeletons. This is consistent with the concept that this species also reproduces sexually by larval dispersal.
The genus Eguchipsammia had already been recorded in Brazilian waters, more specifically from the ASPSP, through E. gaditana (Duncan, 1873) (Cairns, Reference Cairns2000). The coral E. cornucopia is distinguished from the only Brazilian congener in having a larger corallum, a deeper fossa and a better developed columella (see also Cairns, Reference Cairns2000).
DISTRIBUTION
Western Atlantic: Florida; Bahamas; Yucatan Channel; Gulf of Mexico; Cuba; south-western Caribbean; from the Gulf of Venezuela to Barbados; Colombia; northeastern Brazil (Cairns, Reference Cairns1979, Reference Cairns2000; Zibrowius, Reference Zibrowius1980; Viada & Cairns, Reference Viada and Cairns1987; Reyes et al., Reference Reyes, Santodomingo and Flórez2010; present study). Eastern Atlantic: Celtic Sea (Zibrowius, Reference Zibrowius1980); Bay of Biscay (Reveillaud et al., Reference Reveillaud, Freiwald, Rooij, Guilloux, Altuna, Foubert, Vanreusel, Roy and Henriet2008); Gulf of Gascony. Bathymetric range: 91 to 960 m.
RANGE EXTENSIONS
Additionally to the report of P. senegalensis and E. cornucopia, the present study also expands the Brazilian occurrence of nine species previously recorded in Brazil (Table 2).
Table 2. Brazilian azooxanthellate scleractinians with range extensions in Brazilian waters. *, geographical or bathymetric range extensions.
DISCUSSION
According to Kitahara (Reference Kitahara2007), the Brazilian coast can be considered as a transition region between the Caribbean and sub-Antarctic azooxanthellate coral fauna. However, among the 63 azooxanthellate scleractinians recorded from the Brazilian EEZ, 16 have disjunct distribution (Table 3), with gaps particularly on the north-eastern Brazilian coast (see Cairns, Reference Cairns1979, Reference Cairns2000; Castro et al., Reference Castro, Pires, Medeiros, Loiola, Arantes, Thiago, Berman, Lavrado and Ignacio2006; Kitahara, Reference Kitahara2007; Pires, Reference Pires, George and Cairns2007). Apart from these species, Deltocyathus eccentricus Cairns, Reference Cairns1979 and Polymyces fragilis (Pourtalès, 1868) are considered to have disjunct distribution because they display more than 14° of latitudinal gap between the northernmost Brazilian record and their subsequent southern record (15°35′S and 29°20′S, respectively).
Table 3. Summary of the azooxanthellate scleractinian distributional gaps in Brazilian waters.
Apart from Tubastraea coccinea Lesson, 1829, an invasive species in Brazilian waters that most probably migrated through oil platforms (Paula & Creed, Reference Paula and Creed2004), the disjunct distribution of all other azooxanthellate scleractinians in Brazilian waters is most probably due to low sampling efforts.
Beside the first record of 2 species of azooxanthellate scleractinians in the south-western Atlantic, the new distributional records reported herein are a step forward in our understanding of this poorly understood fauna. To summarize, the present study decreases the gap between the previous Brazilian records of Caryophyllia ambrosia caribbeana Cairns Reference Cairns1979, reporting this species from Fernando de Noronha Island, which indicates that this species probably has a continuous distribution along the Brazilian north-eastern coast. Furthermore, the new record of Flabellum apertum Moseley, 1876 from Potiguar Basin (northern Brazilian coast) is the northernmost record of this species thought to be restricted to temperate/sub-Antarctic waters.
With the addition of Polycyathus senegalensis Chevalier, Reference Chevalier1966 and Eguchipsammia cornucopia (Pourtalès, Reference Pourtalès1871), the number of azooxanthellate scleractinians in Brazilian waters total 65. However, we believe that this number is still an underestimate for the species richness in this region.
ACKNOWLEDGEMENTS
The authors thank Dr José Carlos Nascimento de Barros (Department of Fisheries and Aquaculture of the UFRPE) for his solicitude in donating some of the specimens examined, Dr Deusinete Tenório for facilitating the access to the invertebrate collection of the Department of Oceanography of the UFRPE, the anonymous referees for their suggestions, the Federal Rural University of Pernambuco, for authorizing the use of its facilities and for helping with editing our English. Lastly, we thank CNPq for the post-graduate scholarship to R.T.S.C. and for the Research Productivity fellowship to F.D.M.A.
