Australoheros angiru, Říčan, Oldřich, Piálek, Lubomír, Almirón, Adriana & Casciotta, Jorge, 2011

Říčan, Oldřich, Piálek, Lubomír, Almirón, Adriana & Casciotta, Jorge, 2011, Two new species of Australoheros (Teleostei: Cichlidae), with notes on diversity of the genus and biogeography of the Río de la Plata basin, Zootaxa 2982, pp. 1-26: 15-18

publication ID

http://doi.org/ 10.5281/zenodo.200605

DOI

http://doi.org/10.5281/zenodo.6192230

persistent identifier

http://treatment.plazi.org/id/FA2F6911-8609-FFCA-22A4-FDCDFC3AF89A

treatment provided by

Plazi

scientific name

Australoheros angiru
status

sp. nov.

Australoheros angiru   sp. nov.

( Figs 7 View FIGURE 7 , 8 View FIGURE 8 , 9 View FIGURE 9 ).

Cichlasoma   ” facetum— Staeck 1998 a: 62 –63; 1998 b: 81–85 “ Cichlasoma   ” sp. Iguaçu — Staeck 2003: 64 –65

Cichlasoma   ” sp. Iguaçu — Stawikowski and Werner 2004: 455 Australoheros   sp. jacutinga — Říčan and Kullander 2006: 6 Australoheros   kaaygua— Říčan and Kullander 2008: 28 (in part)

Holotype. MCP 13937 View Materials , 73.2 mm SL, Brazil, Santa Catarina State, rio Uruguai drainage, rio Jacutinga, road BR 283 from Ceará to Concordia, col: Bergmann et al., October 1988.

Paratypes. 13 specimens, 24.6 –77.0 mm SL, all from Brazil. Santa Catarina State, rio Uruguai drainage: MCP 13383 View Materials , 6 ex., 24.6 –77.0 mm SL, rio Jacutinga, road BR 283 from Ceará to Concordia, col: Reis et al., February 1989. MCP 12509 View Materials , 1 ex., 75.0 mm SL, same data as holotype. MCP 13011 View Materials , 6 ex., 44.2–61.4 mm SL, rio Jacutinga, road BR 283 from Ceará to Concordia, col: Reis et al., December 1988.

Additional non-type material. Paraná State, rio Iguaçu drainage: NUP 3913, 2 ex., rio São Pedro, tributary to rio Iguaçu, Pinhão county, 26 º05´S, 51 º 45 'W, col: Nupélia staff, March 1993. NUP 3914, 1 ex, rio Iratim (Linígrafo), tributary to rio Iguaçu, Palmas county, boundary with Pìnhão-PR, 26 º05´S, 51 º 45´W, col: Nupélia staff, April 1993. NUP 3915, 1 ex, rio São Pedro, tributary to rio Iguaçu, Pinhão county, 26 º05´S, 51 º 45 'W, col: Nupélia staff, March 1993. Rio Grande do Sul State, rio Uruguai drainage: MCP 46328 View Materials , 13 ex., Sanga das Aguas Frias, Irai, col: Malabarba et al., 1985. Argentina, Misiones province, río Uruguay drainage: ZSM 23482 View Materials a, 1 ex., P, río Soberbio, El Soberbio, col: J. Foerster, 1966. ZSM 23060 View Materials a, 4 ex., río Soberbio, El Soberbio, col: J. Foerster, 1966. ZSM 23060 View Materials c, 2 ex. (C&S), río Soberbio, El Soberbio, col: J. Foerster, 1966.

Diagnosis. Australoheros angiru   is one of the most deep-bodied species of Australoheros   (body depth in SL> 49 %; shared with A. guarani   and A. facetus   ). It has been previously associated with A. kaaygua   , but it is the sister species of A. minuano   based on DNA characters.

Australoheros angiru   is distinguished from A. kaaygua   by having less scale rows between anterior end of dorsal fin and upper lateral line (ch 4 states 1–2 vs. 0), by a very narrow or missing caudal base spot, by a pure yellow ground color (vs. yellowish-green), by yellow eyes (vs. dark green), by more scales between anterior end of dorsal fin and upper lateral line (5 vs. 4), more anal fin spines (7 vs. 6), more anal fin rays (> 7 vs. <7), more dorsal fin rays (9 vs. 8), less E0 scales (24 vs.> 25), more L 1 scales (> 17–18 vs. 16), less L 2 scales (8 vs.> 9), and by a being more deep-bodied (49.6 % vs. 43.8 % SL), and having a shorter caudal peduncle (7.4 % vs. 10.4 % SL).

Australoheros angiru   is distinguished from A. minuano   by a large and dominant midlateral blotch, very narrow or missing caudal base spot, by lacking a pinkish body coloration, by a small terminal or subterminal mouth (vs. large supraterminal), by more scales between the anterior end of the dorsal fin and the upper lateral line (5 vs. 4), less anal fin rays (7 vs. 8), less dorsal fin rays (9 vs. 10), and by slight differences in body depth (49.6 % vs. 46.9 % SL) and in preorbital distance (7.3 % vs. 6.0% SL).

For distinguishing characters to all other Australoheros   species see the Notes section.

Description. Based on specimens over 60 mm SL, with notes on smaller specimens. Meristic data are summarized in Table 2, morphometric data are summarized in Table 3.

Comparatively deep bodied (mean body depth 49.6 % SL). Snout short, straight in lateral view. Jaws isognathous. Mouth small.

Scales on head and chest not distinctly smaller than on flanks. Scales in E0 row 23 (3), 24 (16 *), 25 (4). Upper lateral line scales 16 (1), 17 (6 *), 18 (8). Lower lateral line scales 7 (4), 8 (7 *), 9 (4). Scales between upper lateral line and dorsal fin 4 anteriorly, 1 large plus 1 small posteriorly. Cheek scale rows 3 (14 *), 4 (2). About 8 scale rows between the opercular flap and the anterior insertion of the pelvic fin. Dorsal fin with one basal scale row, starting from the 7 th or 8 th spine and running posteriad; interradial scales appear from 14 th or 15 th spine membrane, in single rows. Anal fin with one basal scale row; interradial scales in single rows, from penultimate spine. Caudal fin densely scaled, scales ctenoid; interradial scales in single rows; hind margin of scaly area concave, extending to between one-third and middle of caudal fin.

Soft dorsal fin pointed, extending beyond middle of caudal fin. D. XVI, 9 (16 *), XVI, 10 (13), XVII, 8 (2). Soft anal fin pointed, of about the same length as dorsal fin. A. VI, 7 (2), VI, 8 (3), VII, 7 (17 *), VII, 8 (8), VIII, 6 (1). Anal fin pterygiophores 11 (2), 12 (22 *), 13 (7). First pelvic fin ray longest, extending up to the second anal fin spine. Pectoral fin with a rounded tip, third and fourth rays longest, extending just to the midlateral blotch. P. 12 (11 *), 13 (5). Caudal fin rounded to subtruncate.

All teeth caniniform, slightly curved. Outer row teeth increasing in size symphysiad, upper jaw anterior teeth longest, lower jaw anterior teeth subequal. Number of lower jaw teeth up to 16 in one outer hemiseries, upper jaw tooth row much shorter, with about 7 or 8 teeth in one outer hemiseries. Lower pharyngeal tooth plate not studied. Gill rakers externally on first gill arch, 2 epibranchial, 1 in angle, 5 (4), 6 (11 *), 7 (1) ceratobranchial.

Vertebrae 13 + 13 = 26 (29 *), 13 + 14 = 27 (2). Caudal peduncle with no vertebrae (10) or containing 0.5 (4), 1 (14 *), 1.5 (1) vertebrae.

Color pattern in alcohol. Six to seven vertical flank bars, a caudal peduncle bar confluent with the caudalbase bar, and a midlateral stripe bearing the midlateral blotch in the fourth flank bar (sensu Říčan et al. 2005) make up the principal markings. All fins and body are without conspicuous spots or blotches. The midlateral stripe is more distinct anteriorly from the midlateral blotch than posteriorly, and the midlateral blotch itself is a dominant coloration pattern element. Vertical bars are relatively wide, faint, indistinct in their ventral parts. The midlateral stripe posteriorly from the midlateral blotch does not align with the lower lateral line and aligns with the E 1 scale row and does not continue in the E0 scale row. Posteriorly from the midlateral blotch, the stripe is slightly decomposed into two blotches in the respective vertical flank bars. The blotch posterior from the midlateral blotch is centered in the same scale row as the midlateral blotch (i.e. E 1 scale row), whereas the second blotch is more elongate along the vertical axis and centered in the E 2 scale row, making the impression that the midlateral stripe makes a dorsally directed turn at its posterior end. The arrangement of the bars on the body in essentially the same as described for A. scitulus ( Říčan & Kullander 2003)   . Very small spots present on the bases of some body scales in adult specimens. In juveniles the spotted pattern of the body is much more pronounced, with virtually every scale on the body having a spot at its base, including those in the anterior part of the E 4 scale row (i.e. as in adult A. scitulus   ).

Life coloration. Coloration of life specimens from the rio Uruguai drainage is unknown to us. Staeck (1998 a, 1998 b, 2003: p. 64) photographed specimens from the rio Iguaçu drainage ( Fig. 7 View FIGURE 7 ). These specimens have a yellow ground coloration with dark vertical bars and a dark horizontal stripe. Several other species of Australoheros   have a yellowish ground color, but it is best developed in A. angiru   . The iris is also yellow. The caudal fin has red dorsal and ventral margins and corners. This character is not unique for A. angiru   , and can also be seen in A. kaaygua   and in populations of A. facetus   from the state of Uruguay. Breeding animals have the typical Australoheros   breeding coloration with the horizontal interruption of the black vertical bars in their dorsal portion between the opercle and the midlateral blotch ( Říčan & Kullander 2003; Staeck 1998 a: p. 82, 1998b: p. 62, 2003: p. 65). Females in breeding coloration develop a black blotch in the dorsal fin. Staeck (1998 b, 2003) describes behavior and spawning under aquarium conditions.

Distribution. Australoheros angiru   has a disjunct distribution in the rio Iguaçu and in the upper rio Uruguai. One locality is so far known from the middle río Uruguay in Misiones province, Argentina ( Fig. 10 View FIGURE 10 ).

Etymology. The Guaraní   word angirû   means friend, partner (amigo or compañero in Spanish). The etymology is based on the fact that A. angiru   and A. kaaygua   have been confused as one species ( Říčan & Kullander 2008). New data have however demonstrate that they are two non-sister group species living in the same river drainage (río Iguazú), though not sympatrically.

Notes. Part of Australoheros angiru   material ( MCP 6262) has been previously considered conspecific with A. kaaygua ( Říčan & Kullander 2008)   . The authors were aware of the morphological variation within A. kaaygua   (sensu Říčan & Kullander 2008), but lack of DNA data and of first hand examination of the type series of A. kaaygua   made them sceptical about describing a new species with an additionally unusual distribution (occuring in the same river basin, río Iguazú as A. kaaygua   , but not in sympatry, and at the same time also in the río Uruguay). DNA data from the rio Iguaçu populations in Brazil ( A. angiru   ) however show no relationship to A. kaaygua   in the río Iguazú in Argentina ( Fig. 2 View FIGURE 2 ). DNA data from the río Uruguay are so far lacking. A more detailed morphological analysis ( Fig. 1 View FIGURE 1 ) also supports the notion of two unrelated species, with populations of A. angiru   from both the rio Iguaçu and from the río Uruguay forming a homogenous clade with short intraspecific branch lengths. The sister species of A. angiru   is A. minuano   , while that of A. kaaygua   is A. tembe   ( Fig. 3 View FIGURE 3 ).

The MCP 6262 lot additionally included two species ( Říčan and Kullander, 2008). Nine specimens from this lot are paratypes of Australoheros forquilha Říčan and Kullander, 2008   . Thirteen specimens from this lot represent A. angiru   (previously erroneously treated as A. kaaygua   in Říčan and Kullander, 2008) and were separated into a new lot MCP 46328 View Materials .

Additional diagnostic characters of Australoheros angiru   that separate it from all other species except A. kaaygua   and A. minuano   are as follows. It is distinguished (in decreasing order of overall similarity; except for species from coastal drainages treated as last) from A. charrua   and A. scitulus   by having less scale rows between posterior end of upper lateral line and dorsal fin (ch 3 state 2 vs. 0 vs. 1), less caudal vertebrae (13 vs. 14), in being more deep-bodied (50 vs. 45 % SL), and in having less E0 scales (24 vs.> 25). Additionally distinguished from A. charrua   by details in the shape of the midlatral stripe (see description) and by lacking a pinkish body coloration. Additionally distinguished from A. scitulus   by lacking black blotches on the opercular series, having less anal fin spines (7 vs. 8), less dorsal fin spines (16 vs. 17), less caudal vertebrae (13 vs. 14), in being more deep-bodied (50 vs. 45 % SL), and in having less pectoral fin rays (12–13 vs. 13–14).

Australoheros angiru   is distinguished from A. tembe   by having less scale rows between anterior end of dorsal fin and upper lateral line (ch 4 states 1–2 vs. 0), by a very narrow or missing caudal base spot, a shorter dorsal fin scale cover (ch 1 state 1 vs. 0), less scale rows between the posterior end of the upper lateral line and dorsal fin (ch 3 state 2 vs. 0), by lacking thick lips, by having more anal fin spines (7 vs. 6), less caudal vertebrae (13 vs. 14), and less caudal peduncle vertebrae (0 vs. 3). It is distinguished from A. guarani   , A. facetus   , A. acaroides   and A. taura   by a large and dominant midlateral blotch (except A. facetus   ), very narrow or missing caudal base spot, and details in the shape of the midlatral stripe (see description).

Australoheros angiru   is additionally distinguished from A. guarani   by a small terminal or subterminal mouth (vs. large supraterminal), more anal fin spines (7 vs. 6), shorter preorbital distance (21 vs. 25 % HL), and less C 1 gill rakers (6 vs. 7). Additionally distinguished from A. facetus   by a longer dorsal fin scale cover (ch 1 state 1 vs. 2), more anal fin spines (7 vs. 6), less anal fin rays (7 vs. 8), less pectoral fin rays (12–13 vs. 13–14), and less C 1 gill rakers (6 vs. 7–8). It is additionally distinguished from A. acaroides   by a longer dorsal fin scale cover (ch 1 state 1 vs. 2), shorter caudal peduncle (40 % CPD vs. 50–60 % CPD), by being more deep-bodied (50 vs. 45 % SL), and having a narrower interorbital distance (35 vs. 40–45 % HL). It is distinguished from A. taura   by also lacking a pinkish body coloration, by a small terminal or subterminal mouth (vs. large supraterminal), shorter caudal peduncle (40 % CPD vs. 50 % CPD), by being more deep-bodied (50 vs. 40 % SL), by a narrower interorbital distance (35 vs. 40 % HL), less pectoral fin rays (12–13 vs. 13–14), and less E0 scales (24 vs.> 25).

Australoheros angiru   is distinguished from A. ykeregua   and A. forquilha   by a shorter dorsal fin scale cover (ch 1 state 1 vs. 0), a different scale pattern along anterior border of dorsal fin (ch 2 state 0 vs. 1), less scale rows between posterior end of upper lateral line and dorsal fin (ch 3 state 2 vs. 0), very narrow or missing caudal base spot, absence of opalescent spots below orbit, unpaired fins without checker-board spotted pattern, absence of red colored lower head area and opercular membrane, by a small terminal or subterminal mouth (vs. large supraterminal), less dorsal fin rays (9 vs. 10), less caudal peduncle vertebrae (0 vs. 2 vs. 2.5), shorter caudal peduncle (40 % CPD vs. 60 % CPD), by being more deep-bodied (50 vs. 45 vs. 40 % SL), with a wider head (55 vs. <50 % HL), and in having less pectoral fin rays (12–13 vs. 13–14). Additionally distinguished from A. ykeregua   by a large and dominant midlateral blotch, and more anal fin spines (7 vs. 6). Additionally distinguished from A. forquilha   by less scale rows between anterior end of dorsal fin and upper lateral line (ch 4 state 1 vs. 0), absence of opalescent scale rows on body, and less pectoral fin rays (12–13 vs. 13–14).

Australoheros angiru   is distinguished from all the Atlantic coast species north of A. acaroides   and A. taura   ( A. autrani   , A. barbosae   , A. capixaba   , A. ipatinguensis   , A. macacuensis   , A. macaensis   , A. muriae   , A. paraibae   , A. ribeirae   , A. robustus   , A. saquarema   ) by a longer dorsal fin scale cover (ch 1 state 1 vs. 2), a large and dominant midlateral blotch, details in the shape of the midlatral stripe (see description), shorter caudal peduncle (40 % CPD vs.> 50 % CPD), in being more deep-bodied (50 vs. 45 % SL), with a narrower interorbital distance (35 vs. 40 % HL), less pectoral fin rays (12–13 vs. 13–14), and less E0 scales (24 vs.> 25).

MCP

Pontificia Universidade Catolica do Rio Grande do Sul

ZSM

Bavarian State Collection of Zoology

DNA

Department of Natural Resources, Environment, The Arts and Sport

Kingdom

Animalia

Phylum

Chordata

Class

Actinopterygii

Order

Perciformes

Family

Cichlidae

Genus

Australoheros

Loc

Australoheros angiru

Říčan, Oldřich, Piálek, Lubomír, Almirón, Adriana & Casciotta, Jorge 2011
2011
Loc

Cichlasoma

Rican 2008: 28
Rican 2006: 6
Stawikowski 2004: 455
2004
Loc

Cichlasoma

Staeck 2003: 64
Staeck 1998: 62
1998