taxonID	type	description	language	source
165D87F3FFE2555BFF30F97BFE8CF937.taxon	description	The Colombian records of Pimelodella bockmanni come from terra firme forest streams, tributaries to the main channel of the Amazon River in Colombia, in the southernmost extreme of the country, known regionally as Trapecio Amazónico (Fig. 1). These specimens were originally identified as P. geryi Hoedeman, 1961 by Arbeláez et al. (2008), possibly due to their similar general appearance and pigmentation pattern (Fig. 2). However, Colombian specimens differ from P. geryi by their supraoccipital process not reaching the nuchal plate (vs. in contact), adipose fin longer (35.2 – 40.1 % in SL vs. 23.8 – 25.1 %), and upper lobe of caudal fin longer (vs. lower lobe longer) (Hoedeman 1961; Slobodian et al. 2017). Pimelodella bockmanni was recently described from main right tributaries of the Madeira River in Brazil (Slobodian & Pastana 2018). Although the type series of P. bockmanni was not examined directly, we found that our specimens agree with the morphological information provided in its original description (Slobodian & Pastana 2018), except by having a longer upper lobe of the caudal fin (39.0 – 51.0 % of SL vs. 25.8 – 34.8 %), which can be attributed to the larger size of the examined specimens from Colombia (SL: 86.0 – 113.7 mm vs. 39.8 – 76.9 mm of the type series) (Table 1).	en	Cortés-Hernández, Miguel Ángel, Méndez-López, Alejandro, Donascimiento, Carlos (2023): New records of Pimelodella (Siluriformes, Heptapteridae) from Colombia for the Amazon River basin, and redescription of P. serrata. Zootaxa 5293 (1): 185-195, DOI: 10.11646/zootaxa.5293.1.10, URL: http://dx.doi.org/10.11646/zootaxa.5293.1.10
165D87F3FFE2555BFF30F97BFE8CF937.taxon	distribution	The geographic distribution of Pimelodella bockmanni seems to conform to the Central Blackwater Amazon pattern proposed by Dagosta & de Pinna (2019), which connects the two hydrographic systems with known records of the species, i. e. Madeira and western Amazon (above the mouth of the Rio Negro). Although the Amazon River is a typically white-water system in the Amazonas / Solimıes region, the streams where Colombian specimens were collected drain heavily leached soils, and their waters are poor in nutrients and dissolved solids (Arbeláez et al. 2008). Detailed data on the type of water corresponding to the localities where the type series originated will allow confirmation of this biogeographic categorization. Pimelodella serrata (Fig. 3), is recorded for the first time from Colombia, based on specimens coming from flooded areas (laguna Yahuarcaca) and terra firme streams (quebrada La Arenosa), draining directly to the main channel of the Amazon River in Colombia (Fig. 1). This species was described for San Joaquín, a locality drained by the Machupo River, a tributary of the Iténez River (upper Guaporé drainage) in Bolivia, and was distinguished by four characters in the dichotomous key provided in Eigenmann (1917): 1) absence of conspicuous cutaneous pores associated to the lateral-line sensory canals in the head, whose presence has been useful in the recognition of other species of Pimelodella (e. g. P. longibarbata, P. mucosa) (Cortés-Hernández et al. 2020); 2) adipose fin long (<3 times in SL); 3) anterior and posterior margins of pectoral-fin spine fully serrated (Fig. 4); and 4) maxillary barbel extending from the posterior end of the anal-fin base to beyond the caudal-fin base. All these conditions were corroborated in the specimens from Colombia, as well as all morphometric and meristic characters indicated in P. serrata description and / or verified in the radiographs of its holotype (Table 2). Pimelodella serrata is perhaps one of the most easily recognized species in the genus, due to its peculiar pectoral-fin spine ornamentation, consisting of completely serrated anterior and posterior margins. This condition is also verified in P. chaparae, a species showing a similarly wide distribution in the Amazon basin, albeit extending further north to the separate Colombian Orinoco basin (Cortés-Hernández et al. 2020). Nonetheless, P. chaparae can be differentiated from P. serrata by: adipose-fin base shorter (27.4 – 30.8 % of SL vs. 40.2 – 43.8 %), greater interdorsal distance (7.4 – 14.0 % of SL vs. 1.5 – 2.4 %), longer preadipose length (56.6 – 64.2 % of SL vs. 50.7 – 53.0 %), shallower head (head depth: 26.4 – 32.2 % of SL vs. 42.0 – 45.0 %), larger orbital diameter (19.6 – 25.1 % of SL vs. 15.0 – 17.7 %), narrower interorbital (interorbital width: 12.6 – 18.3 % of SL vs. 19.8 – 21.4 %), shorter maxillary barbel (extending between the middle and the posterior end of the adipose fin vs. surpassing base of caudal fin in P. serrata), and fewer vertebrate (41 vs. 43). In addition to records restricted to the Madeira River drainage (Machado-Allison et al. 1999; Chernoff et al. 2000; Sarmiento, 2000; Bockmann & Slobodian, 2013; Oliveira et al., 2020; Miranda-Chumacero et al. 2022), P. serrata has also been recorded for the Peruvian Amazon, in the Loreto department (Mesa-Vargas et al. 2021), and along with records reported here, show a wide distribution of this species in the piedmont and lowlands of the western Amazon.	en	Cortés-Hernández, Miguel Ángel, Méndez-López, Alejandro, Donascimiento, Carlos (2023): New records of Pimelodella (Siluriformes, Heptapteridae) from Colombia for the Amazon River basin, and redescription of P. serrata. Zootaxa 5293 (1): 185-195, DOI: 10.11646/zootaxa.5293.1.10, URL: http://dx.doi.org/10.11646/zootaxa.5293.1.10
165D87F3FFE75557FF30F8CDFCD4FA32.taxon	description	Below we provide a morphological description of Pimelodella serrata, based on examination of 12 specimens (1 c & s) from Colombia, and photographs and radiographs of the holotype (housed at FMNH). Morphometric data summarized in Table 2. Body moderately deep and elongated, deeper at dorsal-fin origin. Dorsal profile of body rises straight and upward to supraoccipital process origin, then convex to dorsal-fin origin; dorsal-fin base convex, straight and downward from posterior end of dorsal fin to adipose-fin end, and concave along caudal peduncle. Ventral profile of body straight to slightly convex from jaw tip to pelvic-fin origin, slightly concave between pelvic fin and anal-fin origin, anal-fin base straight and upward, and concave along caudal peduncle (Fig. 3). Head conical. Mouth subterminal, upper jaw more pronounced than lower jaw. Premaxilla with two or three rows of villiform teeth and dentary with three or four rows of similar teeth. Anterior naris tubular. Posterior naris rounded, slightly closer to anterior ocular margin than to anterior naris, and anteromedially bordered by a fleshy margin. Nares disposed in a rectangular or slightly trapezoidal arrangement. Barbels thin, elliptical in cross-section. Maxillary barbel surpassing base of caudal fin, extending to anterior third of lower lobe. Outer mental barbel slightly surpassing origin of pelvic fin (Fig. 3). Inner mental barbel reaching pectoral-fin base. Eye placed dorsolaterally, slightly elliptical, its greatest diameter along horizontal axis. Limits of eye well-defined by a free orbital rim. Supraoccipital process subrectangular in shape and long, reaching anterior nuchal plate. Branchiostegal membranes almost entirely free, united to isthmus only at medial apex and not joined to each other anteriorly. Pseudotympanum large and oval, dorsal to posterior process of cleithrum and extending to vertical through dorsal-fin origin. Branchiostegal rays six. Gill rakers on first gill arch 17 – 20 (9); 14 gill rakers associated to anterior margin of ceratobranchial, one on cartilage between ceratobranchial and epibranchial, and five on epibranchial (verified in one c & s specimen). Dorsal fin with spinelet, spine, and six branched rays (9), originating approximately above posterior end of pseudotympanum. Distal margin of dorsal fin slightly convex. Spinelet large with wide base and slightly rounded distal tip. Dorsal-fin spine straight, slender, pungent, shorter than first branched ray (15.5 – 18.3 % of SL) and slightly curved towards distal end. Anterior margin of dorsal spine smooth; posterior margin with serrae along distal third, and small, straight to retrorse dentations along middle third of its length. Anteriormost dorsal-fin pterygiophore inserted above complex vertebra; posteriormost dorsal-fin pterygiophore located anterior to neural spine of vertebra 11. Pectoral fin with distal margin slightly convex, consisting in one unbranched and eight (1), nine (3) or ten (5) branched rays. First pectoral-fin ray curved with basal portion ossified, forming a spine, and distal tip flexible and segmented. Roughly all anterior margin of pectoral-fin spine with small, but well-defined antrorse dentations (35 – 39), plus 2 or 3 distal serrations; posterior margin of pectoral-fin spine bearing 26 – 30 large, retrorse dentations, extending along almost entire margin (Fig. 4). Pelvic fin with distal margin convex. Pelvic-fin origin at vertical through base of last dorsal-fin ray. Tip of pelvic fin surpassing vertical through adipose-fin origin, but not exceeding first fourth of its base. Pelvic-fin rays i, 5 (9); first ray distinctly shorter than second and third rays (first and second branched rays, respectively). Anal-fin margin rounded, with iv, 8 rays (9). First and second anteriormost anal-fin rays embedded in a thick skin fold. Anal-fin origin at vertical through middle of adipose-fin base. Anal-fin adpressed terminus between verticals through 70 and 75 % of adipose-fin base. Tip of anteriormost anal-fin pterygiophore inserted immediately posterior to hemal spine of vertebra 23. Tip of posteriormost anal-fin pterygiophore inserted immediately anterior to hemal spine of vertebra 28. Adipose-fin long (40.2 – 43.8 % of SL), almost in contact with dorsal fin; forming ascending curve in lateral profile with deepest point approximately at vertical through anal-fin origin. Posterior limit of adipose fin as a rounded free lobe. Origin of adipose fin posterior to mid-length of trunk, and approximately at vertical through vertebral centrum 23. Adipose-fin terminus at vertical through vertebral centrum 37. Caudal fin deeply forked, lower caudal-fin lobe slightly longer than upper lobe, and both lobes with pointed tips. Upper lobe with one unbranched and six (1) or seven (8) branched principal rays. Lower lobe with one unbranched and eight branched principal rays (9). Seven rays articulated to dorsal caudal-fin plate (six to hypurals 3 + 4 and one to hypural 5), and eight rays articulated to ventral caudal-fin plate (five to hypurals 1 + 2 and three to parhypural). Parhypural not fused to hypurals 1 and 2. Hypurals 1 and 2 completely fused into single caudal plate. Hypurals 3 and 4 completely fused. Hypural 5 free. Middle caudal-fin ray of upper lobe not articulated to caudal plate. Total vertebrae 43 (c & s). Ribs eight (c & s). Supraorbital canal with seven sensory pores: s 1, s 2, s 3, s 4, s 6 (epiphyseal), s 7 and s 8 (parietal). Pore s 1 located anteromedial to anterior nare. Pore s 2 at end of short membranous tube on internarial space (slightly closer to posterior nare). Pores s 3 and s 4 emerging from canal segment between posterior portion of nasal and anterior portion of frontal. Contralateral epiphyseal branches (s 6) fused, anterior to epiphyseal bar, at posterior margin of anterior fontanel. Pore s 8 emerging dorsally to parieto-supraoccipital bone, from posteriorly directed osseous canal. Supraorbital and infraorbital canals connected posterior to anterior nare. Pore i 1 located posterior to anterior nare. Pore i 3 lateral to posterior nare. Pore i 4 adjacent to ventral margin of eye, at vertical through anterior ocular margin. Pore i 5 ventrally to eye, at end of posteroventrally directed membranous tube. Pore i 6 placed behind eye, at end of posteriorly directed membranous tube. Preoperculomandibular canal with 11 sensory pores. Postotic canal with three sensory pores. Pore po 2 emerging from a posteriorly directed membranous tube, ending dorsally to dorsal corner of branchial opening. Pore po 3 at end of posteriorly directed membranous tube, dorsal to lateral line canal of trunk, and located dorsally to pectoral-fin base. Lateral line canal of trunk long, extending to basal third of interradial membrane between innermost caudal-fin rays. Color in alcohol Background body coloration pale yellow. Ventral region of abdomen whitish. Dorsal surface of head with dense concentration of dark brown chromatophores, extending from snout tip to posterior process of cleithrum. A conspicuous dark spot on spinelet. Dorsal surface of maxillary barbel darker than ventral surface. Mental barbels yellow. A faint and narrow brown midlateral stripe, extending from pseudotympanum, fading posteriorly along caudal peduncle, and ending in caudal-fin base. Dorsal, pectoral, adipose, anal, and pelvic fins hyaline. Lower lobe of caudal fin slightly dark, pigmented only along fin-rays.	en	Cortés-Hernández, Miguel Ángel, Méndez-López, Alejandro, Donascimiento, Carlos (2023): New records of Pimelodella (Siluriformes, Heptapteridae) from Colombia for the Amazon River basin, and redescription of P. serrata. Zootaxa 5293 (1): 185-195, DOI: 10.11646/zootaxa.5293.1.10, URL: http://dx.doi.org/10.11646/zootaxa.5293.1.10
165D87F3FFEB5557FF30F982FB36F8DA.taxon	materials_examined	Amazon River basin: Colombia: Amazonas: Leticia: IAvH-P 8936, 1 (87.5 mm SL), quebrada Sufragio, in front to Zafire station, 04 ° 00 ’ 19.2 ” S 69 ° 53 ’ 55.5 ” W, 7 Dec 2005, F. Arbeláez. IAvH-P 9005, 1 (93.7 mm SL), 1 c & s (86.0 mm SL), same locality and collector as IAvH-P 8936, 9 Dec 2005. IAvH-P 9063, 3 (92.5 – 95.5 mm SL), stream tributary to Calderón, 45 min N from Zafire station, 03 ° 58 ’ 40.14 ” S 69 ° 53 ’ 31.8 ” W, 10 Dec 2005, F. Arbeláez. IAvH-P 9088, 1 (107.9 mm SL), same locality and collector as IAvH-P 9063, 11 Dec 2005. IAvH-P 9138, 3 (106.3 – 113.7 mm SL), same locality and collector as IAvH-P 9063, 13 Dec 2005.	en	Cortés-Hernández, Miguel Ángel, Méndez-López, Alejandro, Donascimiento, Carlos (2023): New records of Pimelodella (Siluriformes, Heptapteridae) from Colombia for the Amazon River basin, and redescription of P. serrata. Zootaxa 5293 (1): 185-195, DOI: 10.11646/zootaxa.5293.1.10, URL: http://dx.doi.org/10.11646/zootaxa.5293.1.10
165D87F3FFEB5556FF30F88EFCACFF0A.taxon	materials_examined	Amazon River basin: Bolivia: San Joaquin: FMNH 57979, holotype (photographs & radiographs), 55.6 mm SL, 5 Sep, 1909, J. D. Haseman. Colombia: Amazonas: Leticia: ICN-MHN 4475, 5 (70.0 – 85.2 mm SL), 1 c & s (70.0 mm SL), laguna Yahuarcaca, 04 ° 11 ’ 24.1 ” S 69 ° 57 ’ 28.3 ” W, 5 Jul 1999, M. Santos & S. Vejarano. ICN-MHN 6600, 1 (101.9 mm SL), río Amazonas, 31 Oct 2002, J. I. Mojica. ICN-MHN 7076, 2 (85.4 – 90.7 mm SL), quebrada La Arenosa, río Amazonas, 04 ° 07 ’ 24.0 ” S 69 ° 57 ’ 05.0 ” W, G. Galvis. ICN-MHN 7417, 2 (88.5 – 96.4 mm SL), laguna Yahuarcaca, 04 ° 11 ’ 24.1 ” S 69 ° 57 ’ 28.3 ” W, 12 Oct 1999. ICN-MHN 15052, 2 (101.2 – 109.8 mm SL), laguna Yahuarcaca, 04 ° 11 ’ 24.1 ” S 69 ° 57 ’ 28.3 ” W, 9 Jul 1999.	en	Cortés-Hernández, Miguel Ángel, Méndez-López, Alejandro, Donascimiento, Carlos (2023): New records of Pimelodella (Siluriformes, Heptapteridae) from Colombia for the Amazon River basin, and redescription of P. serrata. Zootaxa 5293 (1): 185-195, DOI: 10.11646/zootaxa.5293.1.10, URL: http://dx.doi.org/10.11646/zootaxa.5293.1.10
