VAN AMSTERDAM. (Pisces, Siluriformes, Callichthyidae) Abstract. The new species, presently described as Aspidoras. virgulatus, was.

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1 Bulletin Zoologisch Museum S3 VAN AMSTERDAM S3 Vol. 7 No Aspidoras virgulatusn. sp., a plated catfish from Espírito Santo, Brazil (Pisces, Siluriformes, Callichthyidae) H. Nijssen & I.J.H. Isbrücker Abstract Aspidoras virgulatus, a new species Neotropical callichthyid catfish, is described and illustrated. It originates from tributaries Rio Doce, State Espírito Santo, Brazil. INTRODUCTION The new species, presently described as Aspidoras virgulatus, was Aspidoras Von Ihering, 1907, is a genus small found in samples misidentified and recorded by P. de Miranda Ribeiro (1959: callichthyid catfishes with 14 species, all occurring in Brazil, in the states Cearâ, 16) as Corydoras treitlii Steindacbner, 1906, still known only from its typelocality, upper Rio Maranhâo, Goiâs, Minas Gérais, Mato Grosso, Bahfa, and now also in Espîrito Santo. Parnafba, Est. Maranbao, Brazil. The genus Aspidoras is closely/related to Corydoras Lacepède, 1803, from which it is easily distinguished by a relatively small frontal Aspidoras virgulatus n. sp. (Figs. 12; Table I) fontanel plus a small supraoccipital fossa, whereas Cory doras has a single, relatively large, elongate fontanel. Corydoras treitlii (non Steindachner, 1906); P. de Miranda Ribeiro, 1959: 16 (list specimens; in part).

2 MNRJ MNRJ 30.2 MNRJ Material examined. Medial border pectoralfin spine strongly 16 specimens, largest 36.1 mm si. serrated (Fig. 2a). Skin intercoracoid naked. Brazil: Est. Espirito Santo: MNRJ From the posterior side the orbital rim a 5371, holotype, si 32.7 mm; MNRJ (ex MNRJ 5371), 3 series about four granular ridges run up on paratypes, si 2 rrm; ZMA (ex the skull along the rim to the nostrils, almost MNRJ 5371), 1 paratype, si 30.7 mm, Corrego reaching anterior tip the frontals. Dorsal Chumbado, estrada de Linbares (19 22'S, 40 04'W) and pectoralfin spines distinctly shorter than a Sab Mateus ( 18 44' S, 39 53'W), municîpio de adjacent rays. Snout in front nostrils naked Linhares, coll. Comissao do Instituto Oswaldo except for the presence a relatively small Cruz, , 1 paratype, si 27.7 rim, number minute, isolated odontodes. Rio Ouesino, estrada de Linhares a Sao Mateus, Anus with a small, acute posterior papilla. municîpio de Linhares, coll. L. & H. Travassos & Nuchal scutes almost meeting each other along J. Teixeira de Freitas s 5 para dorsal midline, although this midline is covered types, si mm, RibeirSo do Engano, with skin. Part second dorsolateral body scute Vale do Itauna, coll. Com. Inst. Oswaldo Cruz, is ventrally covered by an additional median body , 2 paratypes, si scute which reaches upper part cleithrum. rrm; MNRJ 5409, 2 paratypes, si 28.4 ran; Five additional scutelets adjacent to and around ZMA (ex MRNJ 5409), 1 paratype, si last dorsolateral body scute, and three scutelets 332 mn, Rio Cupido, Sooretama, municîpio de Linhares, coll. L. & H. Travassos & J. Teixeira posterior to last ventrolateral body scute. Colour in alcohol: Holotype (Fig. 1). Basic de Freitas, 1948 (date given for MNRJ 5366 only). body colour yellowish tan; white skin covering ventral area. Description. A prominent, brown, longitudinalstripe runs Proportions and counts are given in Table I. on junctions dorso and ventrolateral body scutes from the fifth dorsolateral body scute, Measurements (in ran) and counts the holotype (female): si (standard length) 32.7, bd almost reaching caudalfin base. Within this (body depth at origin dorsalfin spine) 10.0, stripe a small, darker, oblique line runs along bw (body width at origin pectoralfin spine) the posterior margin each scute. Irregular 9.0, Ids (length dorsalfin spine) 5.6, lps brown pignent around dorsalfin base, predorsal (length pectoralfin spine) 7.0, hi (head length) 97, sn (snout length) 50, lbo (length bony orbit) 2.6, wi (least interorbital width) 4.1, scute, and adiposefin base. A less prominent longitudinal stripe on fifth through thirteenth dorsolateral body scute, about halfway the height between dorsal fin and ca (width coracoid area, between anterior ventrolateral body scutes) 51, dcp (least depth caudal peduncle) 4.5, anterior (frontal) fontanel dorsal border the midlateral stripe. Posteriorly, this stripe is interrupted by a poorly roundish/oval (Pig. 2b), posterior (supraoccipital) fossa present (Fig. 2b); D (dorsal pigmented area on almost two scutes. Large illdefined, darkbrown blotches on fin) with a spine and7 branched rays, last ray first (nuchal) to third dorsolateral body scute; split to its base; Pi (pelvic fin) with one fourth dorsolateral body scute rather pale. Dark unbranched and 5 branched rays; A (anal fin) with brown pignent in naked area adjacent to head and 2 unbranched and 5 branched rays, last ray split in front the midlateral body scute. A series to its base; P2 (pectoral fin) with a spine and 9 small brown blotches, decreasing in size branched rays; C (principal caudalfin rays) 7/7, posteriorly, on first to fourth ventrolateral the outer unbranched; dbs (dorsolateral body body scute, just below midlateral stripe. On scutes) 24; vbs (ventrolateral body scutes) 22; second to sixteenth ventrolateral body scute pas (preadipose scutes) 4. Two pairs rictal (from near distal tip pectoralfin spine to barbels, the longer reaching gill opening base first and second branched analfin ray) ventrally. Cne pair short mental barbels. runs a third longitudinal stripe; the intensity

3 2 ~ 135 pigmentation is intermediate between that this fontanel is mm long, in the largest the other two longitudinal stripes. paratype 1.4 mm, whereas it is 1.0 mm in a para Dorsum and sides ossified areas head type 332 mm si. The longest fontanel was with irregular brown pigjnentation forming small found in specimens 28.1, 311 and 32.7 mm si. dark blotches. Skin covering anterior fontanel It is round, oval, pearshaped, or elongate in with brown pigjnent along margin. Basic colour unossified parts snout whitish. Brown shape. In one specimen we found a slender commisural bar. The posterior fossa is usually pignent forms an irregular pattern lines. visible, though not conspicuous in larger Upper lip arid base rictal and mental barbels specimens. scarcely pigmented. One the paratypes has in the lower lobe Dorsal fin spine, first two rays and the the caudal fin one branched ray less (5) than the membrane between them, rather faintly brown others. The only noteworthï' variation exists in pigmented, forming a stripe to the tip. Adjacent rays with isolated, small, conspicuous brown the number pectoralfin rays: 7 in one, 8 in five, 9 in six specimens. Two specimens have 8 dots, forming three irregular, oblique rows. on one side and 9 on the other side. Frequency Very faint piggnent on adiposefin. Base the number scutes is: dbs/vbs 24/21 in one caudal fin almost devoid pigjnent. About six specimen, 24/22 in four, 25/21 in one, 25/22 in series small brown dots form irregular, five, 25/23 in three, and 26/23 in one specimen. vertical lines on caudalfin rays. Anal fin with Pas is 3 in five, 4 in nine, and about three irregular oblique rows dots from 5 in one specimen. second unbranched to most the branched ray rays. Pelvic fins hyaline. Pectoral fins hyaline, except for some fine, faint greyishbrown on spine and adjacent rays. Paratypes: Five male paratypes (si 24.7 Variability colour pattern: The midlateral stripe is usually solid and conspicuous. It is irregular posteriorly in one the better preserved paratypes. The five paratypes in MNRJ are stained with brown, their pigmentation 33.2 mm) have bristles (enlarged odontodes) on quite faded. Some these paratypes have a mid their cheeks. This sexual dimorphism is also lateral stripe with 4 or 5 large, elongate known in males Cory doras barbatus (Quoy & blotches, considerably darker than the remaining Gaimard, 1824), C. macropterus Regan, 1913, and pignent (reminding the colour pattern in in C. bondi coppenamensis Nijssen, Various Aspidoras spilotus, cf. Nijssen & Isbriicker, 1976: species Loricariidae also have ten promi 124, fig. 14). In one these paratypes the mid enlarged odontodes in males. lateral and ventral stripes are connected through All specimens examined have a small papilla a brown vertical bar. just beyond the anus. In the bristled specimens Both the dorsal and ventral stripe are and in three other specimens (si mm) variable in length. The dorsal stripe is ten this papilla has the shape an arrow. On the interrupted, especially posteriorly. Some speci basis this shape we recognize these 8 mens show more than one interruption (rather nently specimens as males. The holotype and five larger parar reminding a series elongate blotches). In types (si mm) are females, having one paratype nine gradually smaller spots are an acute papilla like the two remaining juveniles visible just below the midlateral stripe, from (si 20.7 nm). Trends in the range first to ninth ventrolateral body scute. variability some body proportions (si, bw, Ids, lps, sn, lbo, wi, dcp) tend to support Pignentation on scutes anterior to fourth dorsolateral body scute usually prominent and this sex determination (see Table I). This trend variable. Snout with even, faint pigment or with was, however, not found in the coracoid width, dense, marblelike markings. Most specimens with where we anticipated a broader area in females. a dark line from the sides upper lip to orbital The relative size and the shape the anterior rim. Fins with a basically similar colour pattern, fontanel varies considerably, and is not although varying in intensity and number spots. correlated with age. In the smallest paratype, The spots in the proximal half the upper caudal

4 8.9) 136 Aspidoras virgulatus were compared with those fin lobe are in some paratypes more prominent given in graphs in than in the lower lobe; in others it is the Nijssen & Isbriicker (1976, figs. 1719), other way around, whereas some specimens show illustrating the same characters the 13 other the same pattern in both lobes. Adipose fin species Aspidoras. A. virgulatus tends to have ten with a small, conspicuous brown spot. a longer pectoralfin spine (lps Bristles the male: In females, the unossi against 4.0 and a longer head (hi 32 fied snout bears a limited number minute, against ) than all other species isolated odontodes, covered by mucous tissue. Aspidoras. The odontodes on the bony parts the snout are larger. In five out the eight males, long, hairlike odontodes produce from small beds mucous tissue. Although not clearly visible in Sympatric occurrence. A. virgulatus was collected with Corydoras prionotos Nijssen & Isbriicker, This most specimens, it is likely that they arise sample (MNRJ 5409) originally consisted from small roundish dermal ossifications. The 4 specimens, identified as Corydoras treitlii odontodes on the unossified parts the snout by P. de Miranda Ribeiro (1959: 16). Three are found in isolated patches, which are up to 10 in number, and arranged into a regular, horizontal series running from the preoperculum these specimens are now paratypes Aspidoras virgulatus, the fourth (recatalogued as MNRJ 10543) is a Corydoras prionotos. to near the sides the upper lip. In some specimens, similarly enlarged odontodes are evenly distributed on preoperculum, suborbital, ACKNOWLEDGEMENTS and anteroventral part the operculum. ïhe remaining odontodes (on snout and head) are some We are much indebted to Dr. A. Leitao de what longer in males than in females, and are Carvalho, Museu Naciona], Universidade Federal embedded in thicker mucous tissue. do Rio de Janeiro, Rio de Janeiro (MNRJ), who loaned the specimens herein described, and Etymology. ' Aspidoras virgulatus 3 s specific name is Latin, meaning striped, alluding to the distinctive trilineate colour pattern the body. permitted exchange 2 paratypes. Mr. L.A. van der Laan, Institute Taxonomic Zoology, Amsterdam (ZMA) made Fig. 1 and Mr. J. Zaagnan (ZMA) polished our sketches for Fig. 2. Discussion. Recently (1976), we published a review the genus Aspidoras Von Ihering, 1907 Thirteen REFERENCES species were recognized, all from Brazil. Aspidoras virgulatus differs from all other species in its colour pattern. In addition, the serration the medial border the pectoralfin spine is stronger in A. virgulatus than in the other species Aspidoras except for A. pauciradiatus (Weitzman & Nijssen, 1970). The proportions and counts MIRANDA RIBEIRO, P. DE, 1959 Catâlogo dos peixes do Museu Nacional. III. Callichthyidae Gill, Publçoes avuls. Mus. nac. Rio de Janeiro, 27: 116. NIJSSEN, H. & I.J.H. ISBRUCKER, The South American plated catfish genus Aspidoras R. von Ihering, 1907, with descriptions nine new species from Brazil (Pisces, Siluriformes, Callichthyidae). Bijdr. Dierk. h6_ ( 1 ) : 107, 131.

5 137 Table I. Proportions and counts A) holotype, B) 5 female paratypes, C) 8 male paratypes, D) 2 juvenile paratypes, and AD) total ranges variation in proportions and counts in all 16 specimens Aspidoras virgulatus n. sp. A B C D Ā D specimen(s) holotype juv. 16 (total) si (mm) sl/bd sl/bw sl/lds sl/lps sl/hl hl/sn hl/lbo V_NI CO hl/wi hl/ca hl/dcp fontanel (run) P2 1,9 I, 89 I, 79 I,9(N=1) I,79(N=15) dbs/vbs 24/ / / / /2123 pas

6 138 Fig. 1. Aspidoras virgulatus n. sp., holotype, sl 32.7 mm. Fig. 2. Aspidoras virgulatus n. sp., a) prile left pectoral spine the holotype; bc) size and shape the fontanels in b) holotype, and c) paratype 20.7 mm sl.

7 139 Dr. H. Nijssen I.J. H. Isbriïcker, M.Sc.Biol. Instituut voor Taxonomische Zoologie (Zoologisch Museum) Universiteit van Amsterdam Postbus HC Amsterdam The Netherlands received : mailing date : 18.VII.1980.