Scartella itajobi, Rangel, Carlos A. & Mendes, Liana F., 2009

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 : 52-55

Scartella itajobi new species

( Figures 1–5 ; Table I and II).

Synonyms. Scartella sp. Mendes, 2000; Mendes, 2006: 818, Arquipélago de Fernando de Noronha, Pernambuco, Brasil.

Holotype. MNRJ 31887, male, 45.7 mm SL, Praia do Atalaia (03°51’S; 32°26’W), Fernando de Noronha Archipelago, Brazil. (see Fig. 1 and Table I)

Paratypes. MNRJ 31888, 2 males, 39.6 – 39.9, and 2 females, 41.1 – 47, same data as holotype. (see Table I)

Additional non-type specimens. UFPB 6090 (10 exs.; 27,0 – 50,0), Brazil, Pernambuco, Fernando de Noronha Archipelago, Praia do Boldró, collector L.F. Mendes, May 1998; LBRP 5613 (10 exs.; 21 – 35.2), Brazil, Pernambuco, Fernando de Noronha Archipelago, Baía do Sueste, collector P.N.S. Costa, 18 June 2000; MNRJ 31889 (5 exs.; 39.9 – 47.2) Brazil, Atol das Rocas (03º50’S 33º49’W), collectors L.F. Mendes & C. Sampaio, 20 October 2002; LNEP-UFF 193 (4 exs.; 41.6 – 43.1) Brazil, Atol das Rocas (03º50’S 33º49’W), collectors L.F. Mendes & C. Sampaio, 22 October 2002.

Comparative material: Scartella cristata (Linnaeus, 1758) : LBRP 3525, 1 ex.: 72.1, Copacabana, Rio de Janeiro, Brazil; LBRP 5302, 1 ex.: 28.4, Arraial do Cabo, Rio de Janeiro, Brazil; UFPB 4000, 3 of 63 exs.: 26.5-32.3, Paraíba, Brazil; ZUEC 3154, 2 exs.: 67.7-67.9, Ubatuba, São Paulo, Brazil; MCP 25826, 1 ex.: 72.3, Rio Grande do Sul, Brazil; USNM 37412, 1 ex.: 88.6, Cuba, Caribbean Sea; ANSP 143431, 7 exs.: 42.7- 80.5, Venezuela, Caribbean Sea; AMS I-31606001, 1 ex.: 82.9, Italy, Mediterranean Sea; ZMH 17966, 1 ex.: 46.0, Cameroon, west Africa; Scartella nuchifilis (Valenciennes, 1836) : USNM 285039, 14 exs.: 27.2-54.9, Ascension Island; Scartella springeri (Bauchot, 1966) : USNM 280137, 10 exs.: 31.0-59.3, St. Helena Island; Scartella caboverdiana ( Bath, 1990) : SMF 18032, Holotype, 1 ex.: 39.8, Cabo Verde Archipelago; SMF 18033, Paratype, 5 exs.: 28.8-36.7, Cabo Verde Archipelago; Scartella poiti ( Rangel, Gasparini & Guimarães, 2004) : MNRJ 21975, Holotype (male), 1 ex.: 85.4, Ponta da Calheta, Ilha da Trindade, Espírito Santo, Brazil, depth 0-1m, collected by J. L. Gasparini, 30 March 1999; Paratypes: LBRP 5616 (female), 1 ex.: 71.6, Enseada dos Portugueses, Ilha da Trindade, Espírito Santo, Brazil, collected by J. L. Gasparini, 07-08 April 2001; LBRP 5617 (female): 71.8, Ilha da Trindade, Espírito Santo, Brazil, collected by J. L. Gasparini, 29-04 Apr 1999; MNRJ 21976 (male): 79.3, Ponta da Calheta, Ilha da Trindade, Espírito Santo, Brazil, collected by J. L. Gasparini, 29-04 Apr 1999.

TABLE I. Morphometric and meristic data from selected type specimens of Scartella itajobi sp. n.. Measurements are

expressed as percentages of standard length, except orbital diameter (expressed as percentage of head length).

Diagnosis. Scartella itajobi n. sp. is distinguished from its Atlantic congeners by the following combination of characters: a small blue spot on the 2nd dorsal spine (noted mainly in adult males), head with tiny black spots (vs. speckles absent in Scartella cristata ), modally 14 segmented dorsal-fin rays (vs. 15 in S. cristata from Brazilian localities, S. caboverdiana , and S. nuchifilis ; and 16 in S. springeri ), modally 15 segmented anal-fin rays (vs. 16 in S. poiti , 17 in S. cristata from Brazilian localities, S. caboverdiana , and S. nuchifilis ; and 18 in S. springeri ), and modally 23 caudal vertebrae (vs. 24 in S. cristata from other Brazilian localities, S. caboverdiana , and S. nuchifilis ; and 25 in S. springeri ) (see Table II).

TABLE II. Frequency distribution in counts of dorsal and anal rays in species of the genus Scartella from several

localities of Atlantic Ocean, including the Fernando de Noronha Archipelago. Bold data in X columns indicates

detectable differences in the Brazilian species mean.

Dorsal rays Anal rays

Species n localities 13 14 15 16 17 X 14 15 16 17 18 X S. cristata 48 Brazilian coast - 7 33 8 - 15.0 - 1 11 31 5 16.8

S. poiti 28 Trindade Island, Brazil 3 22 3 - - 14.0 - 12 16 - - 15.6

Scartella itajobi 34 Fernando de Noronha 3 23 8 - - 14.1 1 20 13 - - 15.4

n. sp. Archipelago, Brazil

Description. Dorsal-fin rays XII, 13 – 15 (14), 13 in 3 specimens and 15 in only 2 specimens. Anal-fin rays II, 15 – 16 (15), 16 in 30% of specimens; segmented caudal-fin rays 8; pectoral-fin rays 14; pelvic-fin rays I, 3; caudal vertebrae 23 – 24 (23).

A single dorsal fin present; lateral line short, never extending beyond the 1st segmented dorsal ray. Cirri present in the anterior nasal opening, on top of eyes, and in the nuchal area (a longitudinal line of tentacles between the eyes and the origin of the 1st dorsal spine). Pelvic fin with the third segmented ray tightly joined to the second and separated only in their extremity by a thin membrane.

Body moderately elongate, without scales. Mouth low on the head and horizontal; maxilla reaching posteriorly to a vertical through the centre of eye. Two short canine teeth posteriorly in the dentary, at edge of incisiform series, but never on premaxilla.

Color pattern in life. Markedly variable depending on habitat. Body with a light green and caramel (juveniles and females) to dark-brown background color (adult reproductive males); most individuals with six dark brown irregular bars on body (see Fig. 2 ); upper half of body next to the basis of dorsal fin with small white spots; head with diagonal dark line, well marked just below the eye, separating a light cream area which extends from snout to the cheek (see Figs. 2 and 3 ); lips pale green to light brown with cream-colored borders; presence of tiny dark spots on head and anterior region of body (mainly on the base of pectoral fins). Small nuchal cirri striped with dark brown and light green. Interradial membranes of the dorsal fin green to light brown with small white blotches. Posteriomedial region of body speckled with small dark brown spots. Caudal fin with brown irregular bands. Blue ocellated spot present in membranes between the 1st and 3rd dorsal spines (well marked in adult males).

Color in alcohol: Body with a light brown to dark-brown background color; usually six dark irregular bars on body; lower half of body usually paler; head and antero-ventral portion (including the lips and pelvic fins) always light brown lacking small dark spots. Posterior portion of body, membrane of the dorsal fin, proximal portion of the anal-fin, pectoral fin, and caudal fin speckled with small dark spots. These spots are more concentrated on the posteriomedial region of the body. A dark spot (blue in life) is usually present in the membranes between the 1st and 3rd dorsal spines. Juveniles with cream body coloration and bleached fins with very few dark spots.

Geographic range, habitat and natural history. Scartella itajobi n. sp. was collected in shallow-waters and tide pools of the Fernando de Noronha Archipelago (03°51’S, 32°26’W); a volcanic island located 345 km off northeastern Brazil. This archipelago's 20 islands are characterized by clear waters, low coral diversity and are influenced by the warm South Equatorial Current and Atlantic Equatorial Current ( Sampaio et al., 2004). The new species also occurs in Atol das Rocas (sensu Moura & Rosa, 1997; L. Mendes, pers. obs.), an atoll formed by the growth of reefs on the submerged peaks of the submarine ridge distant 100 km to the west of Fernando de Noronha Archipelago. It is also the only atoll in the South Atlantic Ocean and one of the smallest in the world (IUCN, 2000). The specimens from Atol das Rocas have similar counts and color patterns (see Fig. 4 ) to those of the new species. Thus, we consider the specimens from Atol das Rocas to be conspecific making Scartella itajobi n. sp. an endemic of the Noronha-Rocas island complex. Other endemic reef fishes are commonly found in the Noronha-Rocas insular complex (e.g. Stegastes rocasensis (Emery) ; Storrsia olsoni Dawson ; Starksia multilepis Williams & Mounts ; Elacatinus sp.; Lythrypnus sp.; Malacoctenus sp.; Xyrichthys incandescens Edwards & Lubbock ). Like its congeners, Scartella itajobi n. sp. is extremely tolerant to salinity and temperature variations ( Bauchot & Pras, 1993; Mendes, 2000; Mendes, 2006).

The new species of Scartella was frequently observed in tide pools of Fernando de Noronha Archipelago ( Mendes, 2006), co-inhabitants include other blennies ( Ophioblennius trinitatis and Entomacrodus vomerinus ), gobies ( Bathygobius aff. soporator and Coryphopterus glaucofraenum ), labrisomids ( Labrisomus nuchipinnis , Labrisomus kalisherae , Starksia multilepis and an undescribed species of the genus Malacoctenus ), Rocas damselfish ( Stegastes rocasensis ), wrasses ( Thalassoma noronhanum ), and a few morays ( Echidna catenata , Enchelycore carychroa ). In this study, some individuals of the new species were also found in small crevices of emerged rocks (2 meters above sea surface), remaining up to 20 minutes out of the water, probably avoiding predators.

Etymology. The name of the species signifies “green stone or emerald” (ita = stone; jobi =green) in “Tupi”, the native South-American language once spoken in Brazil, and refers to the emerald-green color of individuals of the new species (see Figure 3 ) and an allusion of Fernando de Noronha Archipelago, the type locality of new species, known by “The Emerald of Atlantic”.

Remarks. Until now, individuals of Scartella from Fernando de Noronha Archipelago were misidentified as S. cristata ( Fig. 5 ), the same species reported from the Brazilian coast. Scartella itajobi n. sp. was previously misidentified as S. cristata possibly due its cryptic behavior and resemblance to this species. A similar misidentification happened with Scartella poiti ( Rangel, Gasparini & Guimarães, 2004) , recently described from another Brazilian oceanic island (Trindade Island), which had previously been identified as S. cristata ( Rangel, 2003; Rangel et al., 2004).

Figures

FIGURE 1. Scartella itajobi, n. sp., holotype MNRJ 31887, 45.7 mm SL, male, Praia do Atalaia, Fernando de Noronha Archipelago, Brazil. (Photo: Carlos A. Rangel)

FIGURE 2. Pair of Scartella itajobi, n. sp., male (right) and female (left), rock pool of Praia do Boldró, Fernando de Noronha Archipelago, Brazil. (Photo: Sergio R. Floeter)

FIGURE 3. Scartella itajobi, n. sp., typical behavior in rock pools, Fernando de Noronha Archipelago, Brazil. (Photo: Sergio R. Floeter)

FIGURE 4. Scartella itajobi, n. sp., rock pool at Atol das Rocas, Brazil. (Photo: Bertran Feitoza)

FIGURE 5. Scartella cristata, rock pool in Abrolhos Area, NE Brazil. (Photo by R. Z. P. Guimarães)