Dasyloricaria paucisquama, Londoño-Burbano & Reis, 2016

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 : 11-13

Dasyloricaria paucisquama , new species

urn:lsid:zoobank.org:act:9D689322-8BCC-4CAB-9C3E-62081835CCDC

Fig. 7 , Tables 5-6

Loricaria seminuda .— Miles, 1947: 112; fig. 63 (brief description; upper río Magdalena near Honda, Colombia; identification key).

Holotype. MPUJ 6019 , 203.2 mm SL, Colombia, Departamento de Caldas, La Dorada, La Española farm at Zona El Gigante , río Magdalena basin, río Purrio , 5°21’N 74°48’W, 243 masl, 30 Oct 2009, S. Prada et al.

Paratypes. Colombia: MCP 46920 (1, 179.7 mm SL), collected with holotype. CP-UCO 143 (1 c&s, 174.3 mm SL) Antioquia, río Magdalena basin, southern río Samaná, tributary to río La Miel in Butantan, 5°41’N 74°46’W, 189 masl, 31 Jan 2006 , U. Jaramillo. IAvH-P 7683 (1, 157.7 mm SL) Boyacá, Puerto Boyacá, río Magdalena basin, Palagua and Velasquez creeks, 1 Jun 1995 . MPUJ 5189 (1, 187.0 mm SL) Caldas, La Victoria, La Española farm at Zona El Gigante, río Magdalena basin, río Purrio , 5°22’N 74°47’W, 226 masl, 25 Feb 2010 , S. Prada et al. MCP 48238 (1, 157.5 mm SL) Caldas, La Dorada, Purrio , río Magdalena basin, quebrada La Rica, 5°21’N 74°48’W, 259 masl, 23 Feb 2010 , S. Prada et al.

Diagnosis. Dasyloricaria paucisquama is diagnosed by a single autapomorphy: the posterolateral border of the lateral ethmoid is slightly extended but does not contribute to ventral portion of the orbital rim (character 7.1). Additionally, this species can be differentiated from its congeners by having four to six central abdominal plates on each row (vs. seven to 12 plates) and a pelvic fin never reaching to the anal-fin origin (vs. pelvic fin always reaching to the anal-fin origin).

Description. Dorsal profile of head straight from tip of snout to supraoccipital process. Dorsal profile of body convex from posterior of head to beginning of dorsal-fin base, then straight from that point to caudal-fin origin. Plates at dorsal-fin base forming slight depression. Dorsal margin of orbit elevated; postorbital notch present. Head broad, its width larger than its length. Snout triangular in dorsal view, lateral borders of head broad, with welldeveloped, thin hypertrophied odontodes in adults.

Upper lip with broad filaments never covering premaxillary teeth and laterally, with short and thin filaments on rictal barbel. Posterior border of lower lip with filaments not as broad as but longer than those on upper lip. Teeth slender and long in premaxilla and dentary. Teeth bifid with, main cusp broader than and almost twice as long as lateral cusp.

Central abdominal plates generally larger than in congeners, always arranged in two rows of 4-6 plates, with or without intervening naked spaces between them and lateral abdominal plates, but always in contact with plates bordering preanal plate; naked space never wider than one row of plates. Anterior abdominal plates irregular in size; with naked area between anterior most plates and posterior border of lower lip. Area next to pectoral-fin origin without plates. Plate in mid-ventral and median lateral series with well-developed keels. One pair of predorsal plates between supraoccipital and nuchal plate with two well-developed keels.

Posterior dorsal-fin margin straight; distal tip of adpressed fin reaching sixth plate posterior to dorsalfin base. Posterior pectoral-fin margin straight, first and second branched ray longest and reaching to or barely surpassing pelvic-fin origin. Posterior pelvic-fin margin straight to slightly convex; second and third branched rays longest but not reaching anal-fin origin. Distal anal-fin margin straight to rounded; second branched ray longest. Tip of adpressed anal fin reaching sixth plate posterior to its base. Posterior caudal-fin margin concave; filament on upper ray absent (possibly due to damage).

Color in alcohol. Ground color of head and trunk dark greyish brown to light brown dorsally; pale yellow or light brown ventrally. Upper lip filaments grey to pale yellow; upper and lower lips pale yellow. Eight transverse, dark, dorsal bars; first crossing eyes, second on supraoccipital and predorsal plates ( Fig. 7 ). Dorsal-, pectoral- and pelvicfin rays and membranes with small black spots. Distal most portions of anal-fin rays with diffuse dark spots. Caudal fin with longitudinal black band along tip of rays.

Sexual dimorphism. Males with slightly hypertrophied odontodes on lateral portions of head and on pectoral and pelvic fins.

Distribution. Dasyloricaria paucisquama is distributed in the upper and middle río Magdalena basin, Colombia ( Fig. 2 ).

Etymology. Dasyloricaria paucisquama is named from the Latin paucis, meaning few, little and squama, meaning scale or plate, in allusion to the smaller number of central abdominal plates typical of this species. A noun in apposition.

Conservation status. Although with scarce lots, current plausible threats to the species were not detected in its distribution area, therefore Dasyloricaria paucisquama could be classified as Least Concern (LC), according to the International Union for Conservation of Nature (IUCN) categories and criteria ( IUCN Standards and Petitions Subcommittee, 2014).

Remarks. Dasyloricaria paucisquama and D. filamentosa are sympatric in the middle río Magdalena, but not in the upper portions of that basin. The only record of D. filamentosa from the upper Magdalena is the holotype of D. seminuda , described from a locality only recorded as “Girardot” and which may be an error, since no further specimens of D. filamentosa were collected in the upper Magdalena. In addition, the record of Miles (1947) of D. seminuda near Honda and Huila Department, both part of the upper Magdalena basin, is here regarded as Dasyloricaria paucisquama based on the locality and the drawings in that publication.

Figures

Fig. 7. Holotype of Dasyloricaria paucisquama, MPUJ 6019, 203.2 mm SL, Colombia, Caldas Department, La Dorada, La Española farm at Zona El Gigante, río Purrio, río Magdalena basin, 5°21’N 74°48’W, 243 masl.

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).