Peristedion barbiger ( Garman, 1899 )

Tenda, Miki & Kawai, Toshio, 2012, Record of the Armored Searobin Peristedion barbiger (Garman, 1899) (Actinopterygii: Teleostei: Peristediidae) off Peru with Taxonomic Notes, Species Diversity 17 (2), pp. 135-144 : 135-143

Peristedion barbiger ( Garman, 1899)

( Figs 3–8 ; Tables 1–4)

Peristedium barbiger Garman, 1899: 110–112 (type locality: off Pacific coast of Panama).

Peristedion barbiger: Teague 1961: 14–15 (type locality); Chirichigno F. and Vélez D. 1998: 262–263 (off Peru); Chirichigno F. and Cornejo U. 2001: 175 (off Peru); Kawai 2009: 248 (off Peru); Bussing 2010: 1156 (off Pacific coast of Costa Rica).

Peristedion sp. aff. barbiger: Chirichigno F. and Vélez D. 1998: 260–261 (off Peru); Chirichigno F. and Cornejo U. 2001: 175 (off Peru).

Material examined. Peru (285 specimens): HUMZ 167926–167928 , 3 specimens, 137–142mm SL, 4°04.0′S, 81°10.3′W to 3°51.5′S, 81°13.9′W, 300–316 m depth, 18 Aug . 1999; HUMZ 167960–167961 , 2 specimens, 159– 171 mm SL, 3°45.9′S, 81°18.8′W to 3°47.3′S, 81°20.1′W, 531– 505 m depth, 10 Aug . 1999; HUMZ 168024–168028 , 5 specimens, 147–153 mm SL, 3°37.8′S, 81°12.4′W to 3°39.5′S, 81°13.5′W, 235–256 m depth, 10 Aug . 1999; HUMZ 173419 , 1 specimen, 165 mm SL, 3°37.9′S, 81°12.5′W to 3°39.4′S, 81°12.5′W, 241–255 m depth, 8 May 2000; HUMZ 173578–173581 , 4 specimens, 106–122 mm SL, 3°40.0′S, 81°01.1′W to 3°41.3′S, 81°02.5′W, 326–332 m depth, 6 May 2000; HUMZ 173618 , 1 specimen, 111 mm SL, 3°45.3′S, 81°03.7′W to 3°45.9′S, 81°03.9′W, 286–289 m depth, 6 May 2000; HUMZ 180062–180066 , 5 specimens, 166–182 mm SL, 5°18.6′S, 81°18.9′W, Sep . 2001; HUMZ 180145–180147 , 3 specimens, 164–210 mm SL, 3°39.4′S, 81°11.7′W to 3°39.7′S, 81°11.8′W, 420–432 m depth, 24 Sep . 2001; HUMZ 185666 , 1 specimen, 156 mm SL, 3°58.6′S, 81°11.4′W to 3°58.1′S, 81°10.6′W, 456– 421 m depth, 20 Sep . 2002; HUMZ 189168 , 1 specimen, 142 mm SL, 5°17.6′S, 81°20.2′W to 5°16.1′S, 81°20.4′W, 134–138 m depth, 16 Oct . 2003; HUMZ 185991 , 1 specimen, 78.0 mm SL, off Peru , 2002; HUMZ 189054–189064 , 189316–189318 , 210443– 210452 , 210454–210462 , 210464–210468 , 210470 , 210472– 210482 , 210484–210489 , 210491–210492 , 210494–210498 , 210500–210501 , 210504–210505 , 210507 , 210510–210511 , 210513–210515 , 210517–210522 , 210524–210528 , 210530– 210538 , 210541 , 210543–210544 , 210546–210552 , 210554– 210564 , 210566–210567 , 210569 , 210571 , 210574–210578 , 210580 , 210582–210588 , 210590 , 210592–210596 , 210598– 210607 , 210609–210621 , 210624–210640 , 210642–210645 , 210647–210649 , 210651–210653 , 210656–210667 , 210670– 210673 , 210675–210679 , 210681–210682 , 210687–210688 , 210691–210693 , 210695–210696 , 210699–210702 , 210704– 20705 , 210707–210718 , 210721–210723 , 210726 , 210728 , 210731–210733 , 210735 , 210737–210739 , 210742 , 210748– 210749 , 210751 , 210755–210756 , 210758 , 210761 , 210790 , 210792 , 212990 , 258 specimens, 77.7– 212mm SL, 3°49.1′S, 80°59.6′W to 3°48.0′S, 80°58.8′W, 157– 155 m depth, 18 Oct . 2003 .

Comparative material. Panama (5 specimens): MCZ 28708, lectotype (designated here), 106 mm SL, 7°26′10″N, 79°53′50″W, 102 m depth, 9 Mar . 1891; MCZ 28707, 3 paralectotypes, 122–146 mm SL, USNM 153601 , paralectotype, 144 mm SL, 7°40′00″N, 79°17′50″W, 232 m depth, 8 Mar . 1891 .

Diagnosis. A species of Peristedion with the following combination of characters: dorsal-fin soft rays 16–19; bony plates in upper lateral row 31–34; lower gill rakers 14–19; total chin barbels 17–25; pectoral fin short, 13.3–17.8% SL; pair of filamentous barbel on lip relatively short, 26.4–57.1% HL; rostral projection spatulate and broad, length 19.7– 39.5% HL; large black spot on spinous portion of dorsal fin.

Description. Counts and proportional measurements provided in Tables 1–4.

Body elongated, covered with bony plates except for ventral side of head anteriorly. Head large and depressed. Distance from snout to dorsal fin nearly equal to head length. Small to large spines on both nasals ( Fig. 4C, D ) in 194 specimens, no remarkable spines on either nasal ( Fig. 4A ) in 72 specimens, and small to large spine on either left or right side ( Fig. 4B ) in 19 specimens. Eyes large. Interorbital deeply concave, width nearly equal to orbital diameter. Rostral projections spatulate, broad and long, with single spine at base of each; tips of rostral projections parallel or angled slightly inward. Four sensory pores on ventral side of rostral projection. Single spine on anterior part of second infraorbital dorso-laterally. Rough ridge present below eye on 4th infraorbital. Preopercular moderately broad, its posterior margin with acutely angled (=rounded) to right-angled flange ( Fig. 5A, B ) or with simple ( Fig. 5C ) or bifurcate spine ( Fig. 5D ). Supraocular and postocular spines absent. Posttemporal spine blunt with low ridge. Two sharp opercular spines present; lower one with ridge. Frontal I spine stout and small on dorsoposterior region of orbit. Frontal II spine weak. Parietal spine strong and large.

Mouth inferior. Posterior tip of upper jaw reaching to below posterior nostril. Posterior end of lower jaw situated below anterior margin of orbit. Gill rakers on first arch warty and serrated. No teeth on jaws, vomer, or palatines. Three groups of barbels on lip ( Table 3); posteriormost pair filamentous and longest, extending to below anterior margin of orbit (rarely extending to below posterior margin of orbit). Six (rarely 5 or 7) groups of barbels on chin ( Table 4). Branchiostegal rays 7. Gill membrane united to isthmus.

Bony plates on body arranged in 4 rows. First and second bony plates in dorsal row larger than other dorsal plates. First and second bony plates before anus very large. Each plate with single backwardly directed spine, except 21st– 28th to 30th–33rd (mode 24th to 32nd) plates of upper lateral row with bicuspid spines ( Fig. 6 ); most posterior such plate ending at penultimate one. Each bony plate in ventral row and before anus with blunt, backwardly directed spine. Tenth and 11th (8th and 9th, 9th and 10th, or 11th and 12th in some specimens) plates in upper lateral row inserting between 6th and 7th (3rd and 4th, 5th and 6th, or 7th and 8th in some specimens) plates in dorsal row ( Fig. 7 ). Two (rarely 3) bony plates before anus ( Fig. 8 ).

Dorsal fin originating between first and second bony plates of dorsal row. Anal fin originating just posterior to anus. Pectoral fin reaching to anus; lower 2 rays detached and thickened. Jointed pectoral fin shorter than, or nearly equal in length to lower detached pectoral fin ray. Pelvic fin soft rays progressively elongated and reaching to anus. Caudal fin truncate.

Color when fresh (based on photograph: Fig. 3A ). Head and body reddish to pink, except for whitish ventral side of head, pectoral fin base, and caudal peduncle. All fins reddish to pink, except for yellowish-brown caudal fin. Spinous portion of dorsal fin with large black spot.

Color in alcohol. Head, body, and fins yellowish brown; large black spot on spinous portion of dorsal fin, very small black dots on soft portion of dorsal fin (faded in some specimens), and black band on caudal fin margin (faded in some specimens).

Distribution. Known only from eastern Pacific, from Costa Rica to northern Peru, in depths of 102–531 m ( Garman 1899; Teague 1961; Chirichigno F. and Vélez D. 1998; Chirichigno F. and Cornejo U. 2001; Kawai 2009; Bussing 2010; present study).

Remarks. Garman (1899) described Peristedion barbiger on the basis of five syntypes, viz., MCZ 28707 (3 specimens), MCZ 28708 (1), and USNM 153601 (1). Later, Teague (1961) examined two specimens from MCZ 28707 as cotypes and USNM 153601 as paratype. Recently, Bussing (2010) used two type specimens (MCZ 28708 and USNM 153601, the latter cited erroneously as USNM 15360) and mentioned that one had been selected as lectotype by George C. Miller, but Miller never published such a designation (William J. Richards, pers. comm.). The five type specimens of Peristedion barbiger are, therefore, still syntypes. To clarify this issue we herein designate MCZ 28708, the specimen chosen by Miller, as the lectotype, whereby the remaining four syntypes (MCZ 28707 and USNM 153601) become paralectotypes.

Comparison. Peristedion currently comprises 23 valid described species and one undescribed species: P. barbiger , P. crustosum ( Garman, 1899) , P. nesium Bussing, 2010 , and P. paucibarbiger Castro-Aguirre and Gracia-Dominguez, 1984 from the eastern Pacific; P. amblygenys Fowler, 1938 , P. liorhynchus (Günther, 1872) , P. nierstraszi Weber, 1913 , P. orientale Temminck and Schlegel, 1843 , P. riversandersoni ( Alcock, 1894) , and P. weberi Smith, 1934 from the Indo- West Pacific; P. cataphractum (Linnaeus, 1758) from the eastern Atlantic; and P. altipinnis Regan, 1903 , P. antillarum Teague, 1961 , P. brevirostre (Günther, 1860) , P. ecuadorense Teague, 1961 , P. gracile Goode and Bean, 1896 , P. greyae Miller, 1967 , P. imberbe Poey, 1961 , P. longispatha (Goode and Bean, 1886) , P. miniatum (Goode, 1880) , P. thompsoni Fowler, 1952 , P. truncatum (Günther, 1880) , P. unicuspis Miller, 1967 , and Peristedion n. sp. “t” (sensu Miller and Richards 2002) from the western Atlantic ( Heemstra 1986; Hureau 1986; Richards 1999; Miller and Richards 2002; Yamada 2002; McEachran and Fechhelm 2005; Kawai 2008; Bussing 2010).

The characteristics of the Peruvian specimens examined in this study are correspond well to those of the lectotype and four paralectotypes examined here ( Tables 1–4); therefore, we identify these Peruvian specimens as P. barbiger .

Peristedion barbiger is easily distinguished from the eastern Pacific P. crustosum and P. nesium in having a higher number of total chin barbels (17–25 vs 13–14 and 10–15 respectively) ( Teague 1961; Richards and McCosker 1998; Bussing 2010), from P. paucibarbiger in having a higher number of bony plates in the upper lateral row (31–34 vs 29) ( Castro-Aguirre and García-Domínguez 1984), from all six Indo-West Pacific congeners in having a lower number of soft rays in the dorsal fin (16–19 vs more than 19) ( Alcock 1894; Fowler 1938; Kamohara 1952; Miller 1974; Yamada 2002; Kawai and Yabe 2006), from the eastern Atlantic P. cataphractum in having a higher number of bony plates in the upper lateral row (31–34 vs 29–30) ( FSFRL 1972; Hureau 1986), from the western Atlantic P. antillarum , P. brevirostre , P. imberbe , and P. thompsoni in having a short pectoral fin (13–18% SL vs more than 18%) ( Teague 1961; McEachran and Fechhelm 2005) and from the western Atlantic P. ecuadorense , P. greyae , P. longispatha , P. miniatum , P. unicuspis , and Peristedion n. sp. “t” in having a moderate number of total chin barbels (17–25 vs less than 14 in the first five species and 34–57 in Peristedion n. sp. “t”) ( Teague 1961; Miller 1967a, b; Miller and Richards 2002; McEachran and Fechhelm 2005), from the western Atlantic P. altipinnis in having longer filamentous barbel (26.4–57.1% HL vs 18.1%) ( Teague 1961), from the western Atlantic P. gracile in having spatulate and broad rostral projections, and a large black spot on the spinous portion of the dorsal fin (vs slender projections and no black spot) ( Teague 1961; Miller and Richards 2002; McEachran and Fechhelm 2005), and from western Atlantic P. truncatum in having fewer lower gill rakers (14–19 vs 20–25) ( Teague 1961; McEachran and Fechhelm 2005).

Peristedion barbiger was reported by Teague (1961) as differing from P. altipinnis in having nasal spines (vs lacking them). While Richards and McCosker (1998) and Bussing (2010) stated that P. barbiger differs from P. crustosum and P. nesium in having weak nasal spines or lacking them (vs having nasal spines in both species). The specimens examined in this study revealed that Peristedion barbiger may or may not have nasal spines ( Fig. 4 ), and that this character is not useful for distinguishing Peristedion barbiger from P. altipinnis , P. crustosum , and P. nesium .

Teague (1961) regarded P. barbiger as having an acutely angled preopercular margin and treated this feature as distinct at the species level from the right-angled margin of P. miniatum , P. truncatum , P. spiniger (now recognized as a junior synonym of P. truncatum : see Miller 1967a), and P. crustosum ; from the backwardly directed spine of P. taeniopterum (now recognized as a junior synonym of P. gracile : see Miller 1967a), P. gracile , P. platycephalum (now recognized as a junior synonym of P. brevirostre : see Miller and Richards 2002), P. brevirostre , P. mcgintyi (now recognized as a junior synonym of P. miniatum : see Miller 1967a), P. thompsoni , and P. imberbe ( Teague 1961) ; and the rightangled margin or rounded flange (=acutely angled margin) of P. crustosum and P. nesium ( Bussing 2010) . However, in specimens of P. barbiger examined for the present study, the shape of the preopercular margin is variable ( Fig. 5 ), so this feature is not appropriate for distinguishing taxa.

Chirichigno F. and Vélez D. (1998) and Chirichigno F. and Cornejo U. (2001) treated a species as Peristedion sp. aff. barbiger as it differed from published accounts of P. barbiger in having 18 dorsal fin soft rays and 14 pectoral fin rays (vs 19 and 15 in P. barbiger ). Some specimens that we examined have 18 dorsal fin soft rays and 15 pectoral fin rays and others have 19 dorsal fin soft rays and 14 pectoral fin rays. We conclude that these differences fall within the scope of intraspecific variation for P. barbiger .

Figures

Fig. 3. Peristedion barbiger. A, HUMZ 189055, 184mm SL; B, MCZ 28708, lectotype, 106mm SL.

Fig. 4. Lateral views of snout showing variation in nasal spine development in Peristedion barbiger. A, HUMZ 189058, 151mm SL, no spine on either side; B, HUMZ 180146, 164mm SL, large spine on right side only; C, HUMZ 189060, 179mm SL, small spine on left side and large spine on right side; D: HUMZ 189061, 160mm SL, large spine on both sides. Arrows point to nasal spines. Scale bars: 5mm.

Fig. 5. Dorsal views of head of Peristedion barbiger, posteriorly showing preopercular margin. A, HUMZ 189063, 185mm SL, acutely angled flange; B, HUMZ 168028, 153mm SL, right-angled flange; C, HUMZ 210625, 120mm SL, simple spine; D, HUMZ 189055, 184mm SL, bifurcate spine. Arrows point to preopercular margins. Scale bars:5mm.

Fig. 6. Ventro-lateral view of pre-caudal region of Peristedion barbiger, showing nine biscuspid bony plates in upper lateral row. HUMZ 210676, 173mm SL. Scale bar: 5mm.

Fig. 7. Lateral view of central part of body of Peristedion barbiger, showing successive bony plates in upper lateral row. HUMZ 210522, 179mm SL.Scale bar: 5mm.

Fig. 8. Ventral views of abdomen of Peristedion barbiger, showing bony plates before anus. A, HUMZ 210446, 173mm SL; B, HUMZ 210671, 165mm SL; C, HUMZ 210679, 176mm SL.Scale bars: 5mm.