Magdalenichthys lundbergi DoNascimiento, Villa-Navarro, Ortega-Lara, Albornoz-Garzón, Méndez-López & Conde-Saldaña, 2025

Magdalenichthys lundbergi DoNascimiento, Villa-Navarro, Ortega-Lara, Albornoz-Garzón, Méndez-López & Conde-Saldaña sp. nov.

( Figs 2–3 View Figure 2 View Figure 3 ; Table 1 View Table 1 )

ZooBank registration: urn:lsid:zoobank.org:act:.

Holotype: CZUT-IC 25785 ( 80.9 mm SL); Colombia, Quindío, Armenia, río Verde , tributary of río Quindío , río La Vieja drainage , Cauca River sub-basin , 04°23’43”N 75°45’60”W, 1105 m a.s.l.; J.L. Lozano & G. Murcia, 26 Oct 2017. GoogleMaps

Paratypes: CIUA 3841 (1, 62.3 mm SL); Caldas , Neira , río Tareas, tributary of río Tapias, 05°13’22.1”N 75°38’14.2”W, 859 m a.s.l.; J.G. Ospina-Pabón, 8 Mar 2015 GoogleMaps . CIUA 3843 (2, 46.0– 63.5 mm SL); Caldas , Neira, río Tapias, close to the bridge, 05°13’23.8”N 75°38’16.4”W, 853 m a.s.l.; J.G. Ospina Pabón, 3 Mar 2015 GoogleMaps . CIUA 3856 (1, 69.3 mm SL); Caldas , Río Sucio , río Sucio, tributary of río Supía, 05°22’44.6”N 75°36’57.9”W, 773 m a.s.l.; J.G. Ospina Pabón, 10 Mar 2015 GoogleMaps . CIUA 3929 (1, 50.5 mm SL); Caldas , Viterbo , vereda La Merced, río Risaralda, 05°05’19.7”N 75°51’15”W, 983 m a.s.l.; J.G. Ospina Pabón, 5 Dec 2014 GoogleMaps . CIUA 3961 (2, 59.4–75.2 mm SL); Caldas , Belalcázar , quebrada El Zancudo, tributary of río Risaralda, 04°57’51.3”N 75°51’30.2”W, 941 m a.s.l.; J.G. Ospina Pabón; 7 Dec 2014 GoogleMaps . CIUA 3982 (1, 51.5 mm SL); Caldas , Viterbo , río Guarne, tributary of río Risaralda, 05°05’29”N 75°52’04”W, 986 m a.s.l.; J.G. Ospina-Pabón, 6 Dec 2014 GoogleMaps . CIUA 5399 (1, 27.9 mm SL); Valle del Cauca , Alcalá, quebrada Los Ángeles, 4.71324°–75.8529°; J. Herrera, 10 Feb 2019 . CIUA 5400 (1, 73.5 mm SL); Caldas , Belalcázar, quebrada El Zancudo, 4.96425°–75.85837°; D. Valencia, 11 Feb 2019 . CIUA 7985 (10, 39.2–72.0 mm SL); Valle del Cauca , Bugalagrande, río Bugalagrande, 04°10’46.9”N 76°08’54.2”W; J. Ospina-Pabón, V.M. Medina Ríos, D. Restrepo Santamaría, 1 Sep 2022 GoogleMaps . CZUT-IC 12230 (3, 29.1–68.7 mm SL); Quindío , Armenia, río Quindío, tributary of río La Vieja, 04°23’45”N 75°45’47”W; L. Arrieta & I. Pareja, 1 Jun 2014 GoogleMaps . CZUT-IC 12368 (8, 35.9–81.5 mm SL); Quindío , Calarcá , río Quindío, tributary of río La Vieja, 04°31’47”N 75°38’25”W; A. Ortega-Lara, 1 Sep 2004 GoogleMaps . CZUT-IC 12397 (6, 24.2–75.3 mm SL); Quindío , Pijao , río Barragán , tributary of río Quindío , río La Vieja drainage, Cauca River sub-basin, 04°20’02”N 75°42’09”W, A. Ortega-Lara, 1 Sep 2004 GoogleMaps . CZUT-IC 12408 (4, 21.6–59.2 mm SL); Quindío , río Barragán , tributary of río Quindío , río La Vieja drainage, Cauca River sub-basin, 04°20’02”N 75°42’09”W; A. Ortega-Lara, 7 Dec 2004 GoogleMaps . CZUT-IC 18353 (1, 70.5 mm SL); Valle del Cauca , Yotoco , río Mediacanoa, tributary of Cauca River, 03°54’17”N 76°23’56”W, 993 m a.s.l.; A. Ortega-Lara & G. Sánchez-Garcés, 3 Aug 2017 GoogleMaps . CZUT-IC 18829 (4, 20.7–44.8 mm SL); Valle del Cauca , Zarzal , río La Paila, tributary of Cauca River, 04°18’36”N 76°02’57”W, 952 m a.s.l.; J.G. Albornoz-Garzón, J.E. García-Melo & B. Melo, 20 Aug 2017 GoogleMaps . CZUT-IC 19240 (2, 41.1–46.2 mm SL); Quindío , río Verde , tributary of río Quindío , río La Vieja drainage, Cauca River sub-basin, 04°23’43”N 75°45’60”W, 1105 m a.s.l.; J.L. Lozano & G. Murcia, 26 Oct 2017 GoogleMaps . CZUT-IC 19332 (2, 30.7–61.4 mm SL); Quindío , río Verde , tributary of río Quindío , río La Vieja drainage, Cauca River sub-basin, 04°23’43”N 75°45’60”W, 1105 m a.s.l.; J.L. Lozano & G. Murcia, 26 Dec 2017 GoogleMaps . CZUT-IC 19392 (1, 58.8 mm SL, 1 c&s, 49.8 mm SL); Quindío , Armenia, río Verde , tributary of río Quindío , río La Vieja drainage, Cauca River sub-basin, 04°23’43”N 75°45’59”W, 1105 m a.s.l.; J.L. Lozano & G. Murcia, 28 Jan 2018 GoogleMaps . CZUT-IC 19240 (2, 41.1– 53.2 mm SL); collected with holotype. CZUT-IC 20459 (4, 46.7–62.3 mm SL), Caldas , Anserma, río Risaralda, 05°10’30”N 75°49’04”W, 1040 m a.s.l.; J.L. Lozano, 12 Dec 2018 GoogleMaps . IMCN 3506 (20, 39.2–85.2 mm SL, 2 c&s, 78.8–87.7 mm SL); Cauca , Santander de Quilichao , río Quinamayó, tributary of Cauca River sub-basin, 03°06’29.6”N 76°32’13.4”W, 975 m a.s.l.; A. Ortega-Lara, 21 Apr 2004 GoogleMaps .

Diagnosis: Magdalenichthys lundbergi differs from all its congeners by number of vertebrae (36–37 vs. 32–33 in M. mompox , 38–39 in M. poira , 40 in M. yariguies ). Magdalenichthys lundbergi is distinguished from M. poira and M. yariguies by having five or more dentary tooth rows (vs. four). Magdalenichthys lundbergi is distinguished from M. mompox and M. yariguies by having the adipose-fin origin opposite to the anal-fin origin (vs. posterior). Magdalenichthys lundbergi further differs from M. mompox by having a parabolic contour of the head in dorsal view, with lateral profiles convex (vs. rectangular, with lateral profiles straight); fewer gill rakers on first arch (3–5 vs. 7–8); first dorsal-fin pterygiophore inserted posterior to neural spine of vertebrae 10–11 (vs. vertebra 9); first anal-fin pterygiophore inserted posterior to hemal spine of vertebrae 23–24 (vs. vertebra 21); upper caudal-fin lobe distinctively longer than the lower lobe (vs. both lobes subequal); shorter caudal-fin lower lobe (16–20.5% of SL vs. 21.9–24.9%); fewer caudal-fin branched rays (13 vs. 15); shorter prepelvic length (35.1–42.6% of SL vs. 42–47.9%); longer adipose-fin base (22.8–29.8% of SL vs. 17.5– 20.9%); wider mouth (36.1–43.7% of HL vs. 28.7–36.3%); shorter maxillary barbel (17.5–23% of HL vs. 22.8–32.1%); and shorter inner mental barbel (8.6–12% of HL vs. 12.5–15.8%). Magdalenichthys lundbergi further differs from M. poira by having modally fewer branched rays in the upper lobe of the caudal fin (six vs. seven); translucent or pale nuchal band inconspicuous and narrow in small specimens, faded or absent in large specimens (vs. conspicuous and wide in specimens of all sizes); pale spot at dorsal-fin origin narrow in specimens of up to 72.1 mm SL, absent in larger specimens (vs. wide and triangular, always present in specimens of all sizes); and adipose fin dusky (vs. hyaline). Magdalenichthys lundbergi is further distinguished from M. yariguies by having fewer anal-fin principal (segmented) rays (9–10 vs. 11–12); insertion of anal fin extending posteriorly to hemal spine of vertebrae 29–30 (vs. vertebrae 33–34), which is externally reflected in a longer caudal peduncle in M. lundbergi (20.1–24.2% of SL vs. 16.3–19.3%); shorter anal-fin base (11.7–14.4% of SL vs. 15.6–18.1%); and shorter maxillary barbel (17.5–23% of SL vs. 24.2–30.9%).

Description: Morphometric data in Table 1 View Table 1 . Refer to Figure 2 View Figure 2 for general appearance. Small heptapterine catfish (largest specimen 80.9 mm SL), with elongated body, elliptical in cross-section at dorsal-fin origin (longest axis vertical), progressively more compressed to caudal region. Dorsal profile slightly convex from snout tip to occipital region, straight immediately posterior to this point to adipose-fin origin, sloping ventrally along adipose-fin base to origin of procurrent caudal-fin rays, and slightly ascending along dorsal membrane supported by procurrent caudal-fin rays. Ventral profile straight to pelvic-fin insertion, slightly concave to anal-fin origin, dorsally sloping along anal-fin base, straight along caudal peduncle to origin of procurrent caudal-fin rays and slightly descending along ventral membrane supported by procurrent caudal-fin rays.

Head depressed, parabolic in dorsal view, dorsally covered by thin skin. Cheek laterally bulged with muscular mass of adductor mandibulae, but muscle not reaching dorsally onto skull roof. Snout short and rounded. Mouth slightly prognathous. Premaxillary teeth arranged in a rhomboidal patch of 5*–9 medial and 8*–11 lateral irregular rows of minute conical teeth. Lower jaw slightly longer than upper jaw. Dentary teeth in 5–8 (7) irregular rows of minute conical teeth, similar to those on premaxilla. Maxillary barbel reaching base of unbranched pectoral-fin ray. Conspicuous groove accommodating anterior part of maxillary barbel along sides of head, extending posteriorly to vertical through posterior margin of posterior nares. Bases of outer and inner mental barbels in a straight line. Mental barbels not reaching base of pectoral fin. Outer mental barbel surpassing branchiostegal membrane. Inner mental barbel reaching edge of branchiostegal membrane. Small subcutaneous eye, dorsal in position and twice longer horizontally than vertical diameter. Anterior naris tubular. Posterior naris closer to anterior margin of eye than to anterior naris, anteriorly bordered by a low fleshy margin. Anterior and posterior internarial widths equal. Nares disposed in a squared arrangement. Branchiostegal membrane free, supported by eight (2)* or nine (1) rays and joined to isthmus only at anteriormost point. Gill rakers on first arch 3–5 (one c&s specimen asymmetrically with one and two gill rakers), located along anterior margin of ceratobranchial.

Lateral line canal complete, reaching caudal skeleton. Supraorbital pore s1 medially adjacent to anterior naris; s2 + i2 pore slightly closer to anterior naris ( Fig. 3 View Figure 3 ), at distal end of posteriorly directed membranous tubule, originating from commissure connecting supraorbital and infraorbital canals; s3 pore not visible externally, inside posterior naris, adjacent to its posterior margin, at notch of cutaneous membrane. Contralateral supraorbital canals connected medially by epiphyseal membranous branch, dorsal to posterior portion of anterior fontanel, without superficial pore; s8 pore (parietal branch) arising from a posteriorly directed membranous canal, externally located posterior to eye, at level of medial margin of eye; s4 and s7 branches and pores absent. Infraorbital pore i1 laterally adjacent to anterior naris, between naris and maxillary barbel base; i3 pore posterior to maxillary barbel base; i4 pore slightly anterior to vertical through anterior margin of eye; i5 pore ventral to posterior region of eye; i6 pore posterior to eye, aligned with ventral margin of eye. Pterotic branch (po2) at posterolateral corner of pterotic. Dentary with seven pores of preoperculo-mandibular canal. Submental pores (pm1) paired. Sixth and seventh mandibular pores approximately at same vertical level, and seventh pore just anterior to lateral articulation between dentary and anguloarticular bones. Subpreopercular ossicle with one pore (pm8). Preopercle with two pores, anterior pore (pm9) originating from membranous tubule lateral to interopercle and posterior pore (pm 10) from membranous tubule passing lateral to ventral portion of opercle. Last preopercular pore (po1 + pm11) at end of membranous tubule, dorsal to dorsoposterior portion of opercle. Axillary branch (ll1) ventral, running posterior to supracleithrum.

Precaudal vertebrae 9 (1)–10 (2), thoracic vertebrae 7 (1), 8 (1) or 9 (1), and caudal vertebrae 27, totalling 36–37 vertebrae. Ribs seven (1) or eight (2). Pectoral fin with i,7 (13)*–8 (7) rays. First pectoral-fin ray (unbranched) soft and shorter than first branched ray. Second branched ray longest. Distal margin of pectoral fin convex. Pelvic fin with i,5 rays. First pelvic-fin ray (unbranched) thick and shortest, second and third branched rays longest. Pelvic-fin origin opposite to dorsal-fin origin, at vertical through vertebra 13 (2). Dorsal fin lacking spinelet, with one unbranched and five (1), six* (29) or seven (3) branched rays ( one specimen out of 18 from with five branched rays), supported by seven pterygiophores. Dorsal-fin margin convex, its unbranched ray slightly shorter than first branched ray; first three branched rays subequal. First dorsal-fin pterygiophore inserted posterior to neural spine of vertebrae 10 (1) or 11 (2) and last pterygiophore anterior to neural spine of vertebrae 16 (1) or 17 (2). Adipose fin long, almost rectangular with attenuated ends and posterior lobe free. Adipose-fin origin at vertical through anal-fin origin. Anal fin with 2 (1)–3 (2) procurrent (unsegmented) rays, 2 (8)–3 (10)* unbranched rays, and six* (8), seven (8), or eight (2) branched rays for a total of nine (16) or 10 (4) principal rays. Posteriormost ray (branched) individually associated to last pterygiophore. Anal-fin distal margin rounded. Anal fin supported by 10 (1)–11 (2) pterygiophores. First anal-fin pterygiophore posterior to hemal spine of vertebrae 23 (2)–24 (1) and last pterygiophore anterior to hemal spine of vertebrae 29 (1)–30 (2). Caudal fin deeply forked with i,7 + 7,i principal rays (two c&s specimens of 35.9 and 68.7 mm SL with either six branched rays in lower or in upper lobe, respectively). Upper lobe of caudal fin distinctly longer than lower lobe, upper lobe generally pointed and lower lobe generally rounded. Procurrent caudal-fin rays 13 (2) or 15 (1) dorsal and 13 (1), 14 (1) or 16 (1) ventral, located posterior to vertebra PU 6. Posteriormost two dorsal and two (1) or three (2) ventral procurrent caudal-fin rays segmented. Caudal skeleton PH + 1 + 2,3 + 4 + 5. Long epural present.

Pigmentation in alcohol: Overall ground coloration dark brown. Dorsal surface of head dark. Pale or translucent (superficial muscles of dorsum visible through it) band inconspicuous and narrow, between dorsal corners of branchial openings in small specimens, fading or disappearing in specimens larger than 70 mm SL. Dorsal surface posterior to nuchal band dark. Transverse elliptical or ovoid pale spot at dorsal-fin origin in specimens of 72.1 mm SL or smaller; spot absent in larger specimens. Base of dorsal and adipose fins with darker region along sides. Ventral surface of head and body pale, with sparse chromatophores posterior to ventral fins. Cheeks slightly lighter than remaining dorsal surface of head, with translucent horizontal band (cheek muscles visible through it) in small specimens. Dark chromatophores aligned along lateral line and myosepta. Maxillary barbel darkly pigmented, darker dorsally. Lateral surface of mental barbels with dark chromatophores, denser on outer barbel. Fin rays and adipose fin dusky, with numerous chromatophores. Interradial membrane of rayed fins hyaline.

Distribution: Magdalenichthys lundbergi is found in the main tributaries of the upper basin of the Cauca River (Quinamayó, Mediacanoa, La Vieja, and Risaralda rivers) ( Fig. 4 View Figure 4 ).

Habitat and ecological notes: Magdalenichthys lundbergi is found in sloped sectors of small to middle width ( 3–25 m) rivers, with turbulent flow and gravel bottom with rocks and boulders, along an elevational gradient from 895 to 1669 m a.s.l. The species can be found syntopically with Characidium chancoense Agudelo-Zamora, Ortega-Lara & Taphorn, 2020 , Saccodon dariensis (Meek & Hildebrand, 1913) , Astyanax sp. , Creagrutus brevipinnis Eigenmann, 1913 , Hemibrycon caucanus (Eigenmann, 1913) , Hemibrycon dentatus (Eigenmann, 1913) , Brycon henni Eigenmann, 1913 , Chaetostoma leucomelas Eigenmann, 1918 , and Cetopsorhamdia nasus . Stomachs of two dissected specimens contained remains of larvae of aquatic insects including: Trichoptera ( Leptoceridae and Hidroptilidae), Plecoptera ( Perlidae ), and Diptera ( Chironomidae ), and of terrestrial groups such as Hymenoptera ( Formicidae ) and Orthoptera. Gonads of three dissected specimens corresponded to two ovate females with 299 ( 59.6 mm SL) and 358 ovocites ( 54.4 mm SL), and a mature male ( 36 mm SL). The species was informally categorized as Vulnerable in Ortega-Lara et al. (2022).

Etymology: The species name is dedicated to John G. Lundberg, in recognition of its seminal contributions to the systematics of pimelodoid and heptapterid catfishes, and for being an inspiring milestone in the first author’s career.