Dasyloricaria latiura (Eigenmann & Vance, 1912)

Londoño-Burbano, Alejandro & Reis, Roberto E., 2016, Taxonomic revision and phylogenetic relationships of Dasyloricaria Isbrücker & Nijssen, 1979 (Siluriformes: Loricariidae), with description of a new species, Neotropical Ichthyology (Neotrop. Ichthyol.) 14 (1), No. e 150120, pp. 1-32 : 8-11

Dasyloricaria latiura (Eigenmann & Vance, 1912) Figs. 5-6 ; Tables 3-4

Loricaria filamentosa latiura Eigenmann & Vance , in Eigenmann, 1912: 13 (type locality: Boca de Certegai, Colombia; lectotype FMNH 124472, BY PRESENT DESIGNATION). Meek & Hildebrand, 1916: 257 (senior synonym of L. tuyrensis ; description, counts and measurements; río Atrato basin, Colombia and río Tuyra, Panama). Eigenmann, 1920b: 14 (río Atrato, Colombia and río Tuyra, Panama).

Loricaria latiura . — Eigenmann, 1920a: 10 (río Atrato basin); 1922: 91, pl. XV, fig. 3 (description; as senior synonym of Loricaria tuyrense ). Miles, 1947: 112; fig. 62d, f, g (brief description; as senior synonym of Loricaria tuyrense ; lower río Magdalena and río Atrato, Colombia, and río Tuyra, Panama; identification key). Dahl, 1971: 92 (junior synonym of Loricaria filamentosa ; distribution, ontogeny; common names in Colombia).

Dasyloricaria latiura .—Isbrücker & Nijssen, in Isbrücker, 1979: 87 (description of Dasyloricaria with D. filamentosa as type species). Isbrücker, 1980: 111 (composition of Dasyloricaria ; distribution;typeserieslocation);1981:10(inidentificationkey for Loricariidae ). Ferraris, 2003: 333 (distribution; synonymy; type material depositories; maximum size; common names). Maldonado-Ocampo et al., 2006: 150 (río Atrato). Covain & Fisch-Muller, 2007: 4 (in identification key for Loricariinae ; Dasyloricaria characters). Ferraris, 2007: 233 (synonymy; type material depositories). Maldonado-Ocampo et al., 2012: 234 (lateral view photo; synonymy; description; color in alcohol; río Atrato basin; location of syntypes). Covain et al., 2016: 5 (in molecular phylogenetic analysis of the Loricariinae ).

Loricaria capetensis Meek & Hildebrand, 1913: 80 (type locality: río Capeti, río Tuyra basin, holotype FMNH 7582; NEW SYNONYM). Meek & Hildebrand, 1916: 259, pl. XII (description; possible synonym of Loricaria filamentosa seminuda ; paratype illustration in ventral view; río Capeti, Panama). Eigenmann, 1920b: 14 (río Tuyra, Panama, between Canal Zone and río Atrato). Ibarra & Stewart, 1987: 53 (holotype number; type locality).

Dasyloricaria capetensis .—Isbrücker & Nijssen, in Isbrücker, 1979: 87 (description of Dasyloricaria with D. filamentosa as type species). Isbrücker, 1980: 111 (composition of Dasyloricaria ; distribution; type series location); 1981: 10 (in identification key for Loricariidae ). Ferraris, 2003: 333 (distribution; synonymy; type material location; maximum body size; common names). Maldonado-Ocampo et al., 2006: 150 (río Atrato). Ferraris, 2007: 233 (synonymy; type material location). Maldonado-Ocampo et al., 2012: 232 (lateral view photo; synonymy; description; color in alcohol; río Atrato basin).

Loricaria tuyrensis Meek & Hildebrand, 1913: 81 (type locality: río Tuyra basin, Panama; holotype FMNH 7583; NEW SYNONYM). Meek & Hildebrand, 1916: 257 (as junior synonym of Loricaria filamentosa latiura ). Eigenmann, 1922: 91 (as junior synonym of Loricaria latiura ). Miles, 1947: 112; fig. 61 (as junior synonym of Loricaria latiura ; in identification key). Dahl, 1971: 92, fig. 101 (as junior synonym of Loricaria latiura ; collection localities; minimum and maximum body size; ontogeny). Ibarra & Stewart, 1987: 54 (holotype number; number of specimens catalogued as paratypes).

Dasyloricaria tuyrensis .—Isbrücker&Nijssen,inIsbrücker,1979: 87 (description of Dasyloricaria with D. filamentosa as type species). Isbrücker, 1980: 112 (composition of Dasyloricaria ; distribution;typeserieslocation);1981:10(inidentificationkey for Loricariidae ). Ferraris, 2003: 333 (distribution; synonymy; type material location; maximum body size; common names). Ferraris, 2007: 234 (synonymy; type material depositories). Covain et al., 2008: 988 (in molecular phylogenetic analysis of the Loricariinae ). Rodriguez et al., 2011: 3 (in molecular phylogenetic analysis of the Loricariinae ). Covain et al., 2016: 4 (in molecular phylogenetic analysis of the Loricariinae ).

Dasyloricaria filamentosa , non-Steindachner, 1878. Maldonado- Ocampo et al., 2006: 150 (río Atrato; specimens actually D. latiura ).

Diagnosis. Dasyloricaria latiura is diagnosed by the following autapomorphies: (1) the two maxillary condyles widely separated (21.2); and (2) the posterior abdominal plates larger than the central abdominal plates (character 72.1). Dasyloricaria latiura is also differentiated from congeners by the following external characteristics: none to four dorsal, transverse dark bars on the body (vs. six to eight dorsal transverse, dark bars); the presence of a black band on the distal portions of the anal-fin rays (vs. scattered black spots on anal fin not forming bands); the presence of a black bar extending over the eyes and, sometimes onto the snout (vs. black bar only extending over the eyes and never onto the snout). The species can be further differentiated from D. paucisquama by having a well-developed plate on the ventral surface next to the pectoral-fin origin ( Fig. 5 ; vs. this plate absent).

Description. Dorsal profile of head convex from tip of snout to supraoccipital process. Dorsal profile of body slightly convex from posterior of head to posterior of dorsal-fin base; and straight from that point to caudal-fin base. Plates along dorsal-fin base forming slight depression. Dorsal margin of orbit elevated; postorbital notch well developed. Snout triangular in dorsal view. Odontodes not well developed.

Upper lip with broad filaments that sometimes cover premaxillary teeth. Posterior border of lower lip and rictal barbel with few thin filaments. Teeth slender and long in both premaxilla and dentary; tooth number increasing ontogenetically. Teeth bifid; main cusp almost twice as long as lateral cusp.

Central abdominal plates always arranged in two rows and contacting lateral abdominal plates. Anterior abdominal plates without regular arrangement and with naked area between anterior most plates and lower lip filaments. One well developed isolated plate next to pectoral-fin origin ( Fig. 5 ); plate not in contact with other plates.

Plates in mid-ventral and median lateral series with welldeveloped keels. One pair of predorsal plates with two welldeveloped ridges between supraoccipital and nuchal plate.

Posterior dorsal-fin margin concave; distal tip of adpressed fin reaching ninth or tenth plate posterior to dorsal-fin base. Posterior pectoral-fin margin straight or slightly convex; spine long, reaching to or surpassing pelvic-fin origin. Posterior pelvic-fin margin straight to somewhat convex; third and fourth branched rays longest andreachinganal-finorigin.Distalanal-finmarginstraight or rounded; second and third branched rays longest. Tip of anal-fin spine reaching seventh or eighth plate posterior of its base. Posterior caudal-fin concave, upper ray extended into long filament, sometimes equal, but never greater than SL.

Color in alcohol. Ground color of head and trunk greyish brown dorsally; pale yellow or light brown ventrally. Upper lip filaments grey or pale yellow; upper and lower lips pale yellow. Up to four transverse dorsal dark bars typically present but sometimes absent; first crossing eyes, second on predorsal paired plates ( Fig. 5 ). Dorsal-, pectoral- and pelvic-fin rays and membranes with small, irregular black spots. Distal most portion of anal-fin rays with black band. Caudal fin with vertical black band along distal margin and dark basal spot.

Sexual dimorphism: Odontodes slightly hypertrophied in males along lateral portions of the head and pectoral- and pelvic-fin spines and sometimes the supraoccipital.

Distribution. Dasyloricaria latiura occurs in the río Atrato basin, on the Caribbean slope of Colombia, and in the río Tuyra basin of the Pacific versant of Panama ( Fig. 2 ). Presence of D. latiura in both the Atrato and Tuyra basins can be explained by the Atrato River emptying into the Tuyra Gulf on the Pacific slope of Panama before the uplift of the Darien mountain range (Rodríguez-Olarte et al., 2011).

Remarks. Eigenmann & Vance’s (in Eigenmann, 1912) description of Loricaria filamentosa latiura is based on 12 syntypes from Boca de Certegui (originally CM 3806 and IU 12695). Seven specimens in CM 3806 were later recataloged as FMNH 55115 and the remaining five in IU 12695 were recataloged as CAS 13187. According to the CAS online catalog, CAS 13187 contains six specimens not indicated as types, and is composed of two original lots (IU 12695 and IU 12694), whose locality is “Soplaviento and Boca de Certegui”. Boca de Certegui is in the río Atrato basin, a location within the known distribution of D. latiura . Soplaviento is, however, in the lower río Magdalena, where only D. filamentosa is known to occur. In addition, Ferraris (2007) reports one syntype of Loricaria filamentosa latiura in USNM 79219 and mentions that the location of four syntypes is unknown. The history of the original syntypes is confusing and for this reason we herein designate a lectotype (FMNH 124472, 220 mm SL, transferred from lot FMNH 55115), in accordance with the article 74 of the International Commission on Zoological Nomenclature (ICZN, 1999).

Dasyloricaria latiura was suggested to be the senior synonym of D. tuyrensis by several authors (e. g. Meek & Hildebrand, 1916; Eigenmann, 1922; Miles, 1947). Meek & Hildebrand (1916), subsequent to their description of D. tuyrensis , examined the syntypes of D. latiura , and concluded they belonged to the same species. Those authors did not elaborate as to the basis for the synonymy, presenting only a brief description of D. latiura based on specimens collected in Panama. No diagnostic features for D. tuyrensis were found in the present study to warrant the separation of that nominal species from D. latiura . Eigenmann (1920b) suggested that D. latiura is present in both the Atrato and the Tuyra basins. In that same year, Eigenmann (1920a) indicated the presence of D. latiura in the Atrato, but not San Juan, a conclusion in agreement with our findings.

The holotype of Loricaria capetensis (FMNH 7582) is a juvenile that differs from adults in various features that led Meek & Hildebrand (1913) to describe juvenile and adults as separate species (juvenile - D. capetensis ; adult- D. tuyrensis ). Both species were described from the río Tuyra, Panama. Meek & Hildebrand (1916) redescribed their Loricaria capetensis , when they noticed its resemblance with D. seminuda in terms of the separation of the central and lateral abdominal plates (diagnostic character proposed for D. seminuda ; see Remarks under D. filamentosa ). That synonymy was not formally proposed because they did not have access to specimens of D. seminuda from the Magdalena basin to permit a proper comparison between populations of the Tuyra and Magdalena. This proposed synonymy is rejected in the present study.

Figures

Fig. 5. Dasyloricaria latiura. IAvH-P 6777, 222.0 mm SL, Colombia, Chocó Department, río Yuto, río Atrato basin, Atlantic versant of Colombia. Arrow indicates plate next to the pectoral-fin origin.

Fig. 6. Lectotype of Loricaria filamentosa latiura. FMNH 124472, 220.0 mm SL, Colombia, Boca de Certegui, río Atrato basin, Atlantic versant of Colombia (photo reproduced from FMNH website with permission of Kevin Swagel).

Fig. 2. Map of northwestern South America (Colombia, Panama and Venezuela) showing the distributions of species of Dasyloricaria. Black dots: Dasyloricaria filamentosa; black squares: D. paucisquama; black triangles: D. latiura; white circle: holotype of Loricaria filamentosa seminuda (=Dasyloricaria filamentosa); white square: holotype of D. paucisquama; white triangle: lectotype of Loricaria filamentosa latiura; and white star: holotype of Loricaria capetensis (= Dasyloricaria latiura) and holotype of L. tuyrensis (= Dasyloricaria latiura).