Graptacme perlonga (Dall, 1881)

Caetano, Carlos Henrique Soares, Scarabino, Victor & Absalão, Ricardo Silva, 2006, Scaphopoda (Mollusca) from the Brazilian continental shelf and upper slope (13 º to 21 ºS) with descriptions of two new species of the genus Cadulus Philippi, 1844, Zootaxa 1267, pp. 1-47 : 20-21

Graptacme perlonga (Dall, 1881)

Figs. 44–45

+ Dentalium perlongum Dall 1881: 36 ; 1889: 76, pl. 27, fig. 6.

+ Dentalium (Laevidentalium) perlongum: Pilsbry and Sharp 1897: 104 , pl. 18, figs. 10, 11; Henderson 1920: 75, pl. 9, fig. 1; Maury 1922: 38; Lange de Morretes 1949: 54; Turner 1955: 313; Rios 1970: 144.

+ Graptacme perlongum: Scarabino 1985: 199 , pl. 72, fig. 1018; 1994: 307, pl. 105, fig. 1506. + Graptacme perlonga: Steiner & Kabat 2001: 446 ; 2004: 629.

Type material

Lectotype MCZ 7752 (designated by Turner, 1955: 319 as " Holotype "); Paralectotypes MCZ 7660, 1 dd, MCZ 7661, 1 dd, MCZ 7663, 1 dd, MCZ 7664, 3 dd.

Diagnosis

Shell long (to 90 mm), slender, solid, almost straight. Surface smooth but apical portion shows longitudinal striae. Apex with a U­shaped notch on ventral side.

Material examined

Lectotype and Paralectotype MCZ 7660 of Graptacme perlonga ; IBUFRJ 13866, sta 517, 1 dd; IBUFRJ 14309, off Bacia de Campos, Rio de Janeiro, 1000–1600 m, 3 lv, 20 dd.

Distribution

USA: North Carolina to Florida; gulf of Mexico; Grenada (Henderson 1920); Brazil: Ceará (Henderson 1920), Bahia and Rio de Janeiro (this study). Living 1000–1600 m (this study), empty shells 200 to 4850 m (Steiner & Kabat 2004).

Remarks

Turner (1955: 319) recognized the specimen from MCZ 7752 as the only one that agrees with the original description and illustration of Graptacme perlonga , wrongly using the term holotype to designate this specimen since Dall (1881) did not designate a holotype. Steiner & Kabat (2004) considered Turner’s " holotype " as the lectotype. Turner’s use of the term " holotype " falls within the conditions of ICZN Art. 74.5 to accept a " holotype " indication as a lectotype designation, because Turner (1955) knewn that Dall (1881) did not select any specimen as holotype. Turner’s lectotype designation is valid.

Henderson (1920) cited specimens from Rio de Janeiro and off Rio de la Plata, Uruguay, the latter also indicated by Scarabino (1973). Penna­Neme (1974) recorded this species from the coast of Maranhão, at Ilha Grande­Rio de Janeiro and south of Brazil. Cabral and Mello (1994: 38, fig. 9) reported it for the states of Ceará and Alagoas. We do not consider those records to belong to G. perlonga , because all were based on specimens gathered in depths ranging from the shore to 170 m, while this species has a bathyalabyssal distribution being collected from depths greater than 200 m (Steiner & Kabat 2004). Additionally, we examined the material from Scarabino (1973) and Penna­Neme (1974) studies, which prooved to be misidentified specimens. Recently, Scarabino (2003) stated that G. perlonga records from off Argentina were obviously due to a mistake in the station number, as suspected previously by Henderson (1920), who added a question mark to this record. Thus, we conclude that the southernmost geographical distribution limit for this species is off Rio de Janeiro, Brazil.

Figures

FIGURES 39 – 56. Genus Graptacme and Fustiaria. (39 – 43) Graptacme calamus, (39 – 40) Lectotype USNM 68117, 19 mm, (41 – 43) IBUFRJ 14232, 18 mm; (44 – 45) Graptacme perlonga, IBUFRJ 13866, 61 mm; (46 – 47) Graptacme semistriolata, IBUFRJ 14247, 35 mm; (48 – 52) Fustiaria liodon, (48) Holotype ANSP 35554, 25 mm, (49 – 52) IBUFRJ 14252, 30 mm; (53 – 56) Fustiaria stenoschiza, (53 – 54) Syntype ANSP 71081, 35 mm, (55 – 56), IBUFRJ 10587, 26 mm.