Rhamdia voulezi Haseman, 1911

Garavello, Julio Cesar & Shibatta, Oscar Akio, 2016, Reappraisal of Rhamdia branneri Haseman, 1911 and R. voulezi Haseman, 1911 (Siluriformes: Heptapteridae) from the rio Iguaçu with notes on their morphometry and karyotype, Neotropical Ichthyology 14 (1), No. e 140111, pp. 1-12 : 6-7

Rhamdia voulezi Haseman, 1911

( Figs. 6-7 )

Rhamdia branneri voulezi Haseman, 1911: 378 , pl. LXXVI; (Porto União da Vitória (current União da Vitória), rio Iguassu (current Iguaçu), Paraná State, Brazil); - Gosline, 1945: 37 (literature compilation); - Fowler, 1954: 558 (literature compilation); -Ibarra & Stewart, 1987: 74 (literature compilation).

Rhamdia voulezi . - Garavello et al., 1997: 77 (citation); -Abucarma & Martins-Santos, 2001: 300 (cytogenetic description); - Baumgartner et al., 2012:135 (citation).

Diagnosis. Rhamdia voulezi is distinguished from the remaining Rhamdia species , with exception of R. branneri and Rhamdia cf. quelen from rio Tibagi, by having both sides anterior and posterior of the pectoral-fin strong serrate in large dents (vs. slightly serrate in fine dents in Rhamdia cf. quelen ). Differ from R. branneri by the dorsal profile almost straight from tip of snout, through supraoccipital and to dorsal-fin insertion (vs. dorsal profile straight between the snout and supraoccipital process and convex from this point to the dorsal fin insertion in R. branneri ). Rhamdia voulezi is also distinct from R. branneri by its dorsal-fin length reaching the origin of the adipose fin when adpressed (vs. adpressed dorsal fin not reaching adipose-fin origin in R. branneri ); maxillary barbel long reaching the origin of adipose fin (vs. maxillary barbel short, not surpassing adipose-fin origin in R. branneri ; longer than the SL in R. cf. quelen ).Ground color of preserved R. voulezi specimens grayish on dorsum to light orange on abdomen (vs. dark or light gray with few large spots and without small black dots over trunk in R. branneri and dark brown spotted in R. cf. quelen ). Rhamdia voulezi differs in corporal proportions from R. branneri by the longer maxillary barbel (178.5 to 374.2% of HL, mean=261.3%; vs. 128.9 to 213.3% of HL, mean= 167.8% in R. branneri ); larger interorbital distance (29.8 to 39.9% of HL, mean 35.2% vs. 30.1 to 41.8%, mean 33.7% in R. branneri ); longer dorsal-fin base (14.3 to 19.0% of SL, mean=16.6% vs. 13.5 to 18.9%, mean=15.7% in R. branneri ); and longer adipose fin length (18.7 to 38.8% of SL, mean 34.5% vs. 23.8 to 34.9%, mean 30.1% in R. branneri ). Rhamdia voulezi also differ in chromosome number and morphology: 2n=58-60 plus one metacentric B chromosome and a simple nucleolus organizer region (NOR) (vs. 2n=58-62 chromosomes, plus one submetacentric B chromosome and multiple NOR system in R. branneri ). Rhamdia voulezi also differ from R. branneri , R. foina and R. itacaiunas by having 9-14 gill rakers (12 in mode) on the first gill arch (vs. 9-14, 10 in mode in R. branneri , 15-20 in R. foina and 5-7 in R. itacaiunas ); differ from R. laukidi by having absence of a diagonal light bar from superior corner of operculum to base of pelvic fin; differ from R. branneri , R. xetequepeque , R. jequitinhonha , R. muelleri and R. poeyi by having shorter orbital diameter: R. voulezi 12.1- 20.2% of HL (vs. 12.9-17.6% in R. branneri , 30.5-36.9% in R. xetequepeque , 20.4% in R. jequitinhonha , 12.1-27.2% in R. muelleri and 20.1-26.2% in R. poey ). Rhamdia voulezi is further distinguished from R. jequitinhonha by their longer caudal peduncle (18.4-21.8% vs. 16.3% SL) and from R. muelleri by the longer interorbital distance 29.8-39.9% HL in R. voulezi (vs. 24.2% in R. muelleri ) and shorter maxillary barbel length: 178.5-374.2% HL in R. voulezi (vs. 73.9-129.0% in R. muelleri ); R poeyi with small serrae of spines on posterior margin of pectoral spine differ from R. voulezi with strong and well developed serrae on both sides; R. voulezi also differ from R. poeyi in caudal fin upper lobe shorter than lower and margin of lower lobe rounded (vs. longer and pointed lower caudal fin lobe in R. poeyi ).

Description. Morphometric and meristic characters are summarized in Tables 1-2 . Dorsal profile almost straight from tip of snout through supraoccipital and to dorsal-fin insertion. Body height between ventral and anal-fin smaller than distance between ending of dorsal fin and anterior insertion of anal fin; caudal peduncle depth small, height near 9.5-13.2, mean 11.0% SL. Distance from ending dorsal and anterior insertion of adipose fin always shorter than dorsal fin basis; head almost conic, occipital process covered by thick skin. Orbits relatively large, near 12.1- 20.2, mean 16.4% HL. Upper maxillae slightly longer than dentary; distal portion of premaxillary dental plate slightly circular; dental plate of mandible slightly decreasing distally and with gap over the mandibulary symphysis; small teeth, almost with same size on premaxillae and dentary. Maxillary barbel flattened, longer and surpassing beginning of adipose-fin insertion. In young specimens, this barbel surpasses anal-fin base; external mental barbel surpassing beginning of pectoral-fin; inner mental barbel surpassing gill opening in juveniles, but not in adults. Posterior cleithral process short. Dorsal-fin spine smooth on both sides. Posterior border of pectoral-fin reaching vertical through the first dorsal-fin branched ray. Pelvic-fin beginning in vertical through anterior or over last ray of dorsal-fin. Anal-fin with rounded distal border. Caudal fin forked; ventral lobe larger than dorsal.

Color pattern of preserved specimens. Ground color generally grayish and with small dispersed black dots; abdomen generally yellowish-orange. Dorsal-fin with a light horizontal line upper to its base; over to this light line the interradial membranes with the same ground color and the branched rays may appear blackish highlighted. Remaining fins with nearly same ground color of body and trunk; interradial membranes hyaline.

Distribution. Known from rio Iguaçu, rio Paraná basin in Brazil ( Fig. 5 ).

Material examined. FMNH 54238 , holotype of Rhamdia branneri voulezi, Porto União da Victória , rio Iguassu (current Iguaçu), J. D. Haseman, 24 Dec 1909 . Paraná: LISDEBE 2292, 3, rio Iguaçu , Porto Lupion, collectors of Ichthyology Surehma, Dec 1979 – Jan 1980 ; LISDEBE 2296, 4, rio Iguaçu , Porto Lupion, Surehma collectors, Dec 1979 – Jan 1980 ; LISDEBE 2293, 1, rio Iguaçu, Porto Lupion , J. C. Garavello & Surehma collectors, May 1979 ; LISDEBE 5529, 2, São José dos Pinhais, rio Iguaçu, marginal lagoons at Torres Avenue, beside of Cambuí reserve , UFSCar collectors, 29 Dec 1984 ; LISDEBE 5527, 1, rio Iguaçu, downriver from the Salto Osorio hydroelectric power dam, municipality of Quedas do Iguaçu, J. C. Garavello, A. S. Soares & J. C. Soares, 14-17 Jan 1990 ; LISDEBE 2297, 4, rio Iguaçu, downriver from Salto Santiago hydroelectric power dam, between municipalities of Laranjeiras do Sul and Chopinzinho, J. C. Garavello, A. S. Soares , R. J. Rodrigues , M. J. Veber & M. M. Paschoa, 5-10 Nov 1990 ; LISDEBE 2295, 3, rio Cavernoso, tributary of rio Iguaçu, near Candói city, J. C. Garavello & A. S. Soares, 19-23 Jun 1998 ; NUP-MU 3893, 1, rio Ocoi, Vila Ipiranga, São Miguel do Iguaçu , Nupélia collectors (25 o 13’S 54 o 12’W), 10 Nov 1988 ; NUP-MU 2664, 1, riacho na Fazenda Picui, São Miguel do Iguaçu, Nupélia collectors (25 o 15’S 54 o 15’W) 22 Mar 1989 ; NUP 5675, 3, Pinhão, Segredo reservoir at Mangueirinha border, Nupélia collectors, 10 May 1993 ; NUP 5674, 7, Pinhão, Segredo reservoir at Mangueirinha municipality border, Nupélia collectors, 17-18 Jun 1993 ; NUP 5673, 6, Pinhão, Segredo reservoir at Mangueirinha border, Nupélia collectors, 24 Mar 1993 ; NUP 5678, 3, Palmas, rio Iratim , border with Pinhão and Mangueirinha municipalities, Nupélia collectors, 21 May 1993 ; NUP 5674, 7, Pinhão, rio São Pedro , Nupélia collectors, 22 Jun 1993 ; NUP 2673, 1, Pinhão, Foz do Areia reservoir, border with municipality of Bituruna, Nupélia collectors, 1 Jul 2001 ; NUP 5716, 1, Pinhão, Foz do Areia reservoir, border with municipality of Bituruna, Nupélia collectors, 28 Aug 1993 ; NUP 5677, 3, Pinhão, Foz do Areia reservoir, border with municipality of Bituruna, Nupélia collectors 12-13 Aug 1993 ; NUP 5679, 2, Pinhão, Foz do Areia reservoir, border with municipality of Bituruna, Nupélia collectors 12-13 Sep 1993 ; NUP 5305, 1 of 29, rio Iguaçu, downriver of Segredo reservoir, municipality of Pinhão at Mangueirinha border, Nupélia collectors, 12 Jul 1993 . Santa Catarina: Porto União: LISDEBE 2347, 2, rio Timbó, tributary of rio Iguaçu at colônia São Pedro, J. C. Garavello & UFSCar collectors, 18-19 Nov 1986 ; LISDEBE 5528, 1, rio Timbó, tributary of rio Iguaçu , colônia São Pedro, J. C. Garavello & UFSCar collectors, 19-20 Nov 1986 .

Figures

Fig. 6. Lateral view of Rhamdia voulezi, LISDEBE 5529, 214.0 mm SL, Brazil, Paraná, São José dos Pinhais, rio Iguaçu, marginal pound and lagoons at Torres Avenue, sides of Reserva do Cambuí.

Fig. 7. Lateral view of holotype of Rhamdia branneri voulezi, FMNH 54238, 122.0 mm SL, Brazil, Paraná, Porto União da Vitória, rio Iguaçu.

Fig. 5. Geographical distribution of Rhamdia branneri and R. voulezi in rio Iguaçu. Each symbol may represent more than one sample.