Ophioblennius trinitatis Miranda-Ribeiro, 1919

Rangel, Carlos A. & Mendes, Liana F., 2009, Review of blenniid fishes from Fernando de Noronha Archipelago, Brazil, with description of a new species of Scartella (Teleostei: Blenniidae), Zootaxa 2006, pp. 51-61 : 57-58

Ophioblennius trinitatis Miranda-Ribeiro, 1919

( Figure 6 ).

Synonyms. Ophioblennius trinitatis Miranda-Ribeiro, 1919 : (original description, Ilha da Trindade, east off Brazil) Ophioblennius atlanticus (not Valenciennes, 1836): Mendes, 2000; Gasparini and Floeter, 2001; Muss et al., 2001; Feitoza et al., 2003; Mendes, 2007.

Material examined: UFPB 6088 (1 lot; 10 specimens: 42.0 – 56.3 mm SL), Brazil, Pernambuco, Fernando de Noronha Archipelago, Praia do Boldró, collector L.F. Mendes, June 1998.

Diagnosis. Ophioblennius trinitatis differs from its congeners by the following combination of characters: modally 22 segmented dorsal-fin rays (vs. 20 in O. macclurei ); and modally 23 segmented anal-fin rays (vs. 21 in O. macclurei ; 25 in O. atlanticus and O. steindachneri ). Counts of other species of Ophioblennius are those of Springer (1962) and Hankins & Baldwin (2002).

Description. Dorsal-fin rays XII, 21 – 22 (22), anal-fin rays II, 23 - 24, segmented caudal-fin rays 8; pectoral-fin rays 15. Presence of a dark-brown spot, located immediately after the ocular globe, of similar or lesser size to the diameter of the pupil; border of eyes with bluish coloration, well marked in superior and inferior margins (see Fig. 6 ).

Color pattern in life. Adults exhibit a brown uniform coloration with pale yellowish fins (see Fig. 6 ). Darker body in anterior upper region and clear ventrally. Lips light-brown to yellowish contrasting with the coloration of the head and body. Juveniles may present bicolor pattern, with the anterior half portion olive green and the posterior half yellowish. In stress situations exhibits a color pattern with transversal light and dark stripes in the head area to the posterior portion of body ( Mendes, 2000).

Geographic range, habitat and natural history. Occurs on the Brazilian coast and Brazilian oceanic islands (São Pedro e São Paulo, Atol das Rocas, Fernando de Noronha, and Trindade). In Fernando de Noronha two distinct morphotypes have been found. The distinguishing features between the two recognized groups (in both young and adult specimens) include color differences, spatial distribution, behavior and morphometrics (see Mendes, 2007). Until now, only one morphotype had been recorded at Atol das Rocas and São Pedro e São Paulo ( Mendes, 2007). In addition, in this study, O. trinitatis was observed at 53 m depth, representing the only occurrence of this species in such depths. On several occasions, O. trinitatis was observed being aggressive towards other Blenniidae species and fighting with them for shelter. The Rocas Gregory, Stegastes rocasensis (Emery, 1972) , a territorial herbivore very common in tide pools, was usually observed chasing individuals of Bathygobius aff. soporator (Valenciennes, 1837) , Entomacrodus vomerinus (Valenciennes, 1836) , Scartella itajobi n. sp. and Malacoctenus sp. (new undescribed species), and rarely chasing exemplars of O. trinitatis , apparently because of their antagonistic behavior in interspecific interactions ( Mendes, 2000). Ophioblennius larvae are frequently captured in deep waters. The adults are restricted to shallow waters and dwell among rocks and coral reefs ( Bath, 1990), where there is considerable wave action ( Smith, 1997). Ophioblennius is reported to feed on filamentous algae ( Randall, 1996).

Remarks. Springer (1962), based on limited material then available, recognized two geographically distinct subspecies based on morphological differences. The Atlantic subspecies, Ophioblennius atlanticus macclurei , occurs in the Caribbean Sea and coastal waters of the southeast U.S.; O. a. atlanticus has an extensive geographical distribution, ranging north to the Azores, south to St. Helena Island and Brazil, west to the western Caribbean, and east to the west coast of Africa. The species (or subspecies) that occurs at Bermuda, reported as O. atlanticus maccclurei , requires additional study. A molecular study ( Muss et al., 2001) examined the phylogeography of Ophioblennius by comparing a 630-bp region of mitochondrial cytochrome b for 171 individuals from ten Atlantic and eastern Pacific localities ( Hankins & Baldwin, 2002). Their results suggest that Ophioblennius comprises six lineages, one Pacific, O. steindachneri , and five Atlantic, which are geographically distributed as follows: 1) Brazil, 2) Caribbean/western Atlantic, 3) São Tomé, 4) Azores/ Cape Verde, and 5) mid-Atlantic ( Ascension / St. Helena). Hence, according Hankins & Baldwin (2002), there are at least five species of Ophioblennius that should be recognized in the Atlantic; names are available in the literature for the following: Caribbean/western Atlantic: Ophioblennius macclurei (Silvester) ; Brazil: Ophioblennius trinitatis Miranda-Ribeiro, Azores /Canaries/Madeira: Ophioblennius atlanticus (Valenciennes) . Therefore, the Ophioblennius species present in Brazilian coastal waters and at some adjacent oceanic islands, is distinct from the other Atlantic species and an available name for this species is Ophioblennius trinitatis (Miranda-Ribeiro, 1919) , which we use in this study.

Figures

FIGURE 6. Ophioblennius trinitatis at Fernando de Noronha Archipelago, Brazil. (Photo: Fabio G. Ribeiro)