Moema beltramonorum Valdesalici 2023, new species
Creators: name: Valdesalici, Stefano
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Cyprinodontiformes
Rivulidae
Moema
Moema beltramonorum

description: Moema beltramonorum, new species
(Figs 1–4, Table 1)
Holotype. MSNG 62480, male, 38.7 mm SL, Bolivia, Beni department, municipality of Bella Vista, swamp near the arroyo Crespo, Rio San Martin, Rio Iténez / Guaporé drainage, 13°14’57.0”S 63°41’46.1”W, 7 February 2022, Christine and Jean Marc Beltramon.
Paratypes. MSNG 62481, two males, 32.2 (C&S) and 36.6 mm SL; two females, 27.3–30.8 mm SL, all collected with the holotype.
Diagnosis. Moema beltramonorum males can be easily distinguished from all congeners by a unique combination of the following characters: presence of humeral blotch (vs. absence, except from M. apurinan, M. beucheyi, M. claudiae, M. funkneri, M. heterostigma, M. nudifrontata, M. ortegai / M. quiii, M. wischmanni), pattern of irregular vertical rows of red dots on flank (vs. dots arranged obliquely, in horizontal lines, rows of dots or absence of dots in M. apurinan, M. beucheyi, M. claudiae, M. funkneri, M. hellneri, M. heterostigma, M. juanderibaensis, M. nudifrontata, M. obliqua, M. peruensis, M. pepotei, M. piriana, M. portugali, M. ortegai / M. quiii, M. schleseri, and M. staecki), brown spots on the entire anal fin and absence of black distal stripe (vs. spots mostly limited on proximal portion and absence of distal stripe in M. apurinan, M. boticarioi, M. claudiae, M. funkneri, M. hellneri, M. heterostigma, M. kenwoodi, M. manuensis, M. staecki and M. wischmanni), pectoral fin with red dots (vs. pectoral fin lacking dots, except in M. boticarioi, M. kenwoodi, M. obliqua, and M. rubrocaudata), caudal fin with a single stripe on ventral portion (vs. stripe present also on dorsal portion in M. rubrocaudata and some populations of M. schleseri), and presence of light blue iridescence with black dots on caudal fin dorsal portion (vs. never a similar combination in the remaining congeners).
Description. Morphometric data of holotype and paratypes are presented in Table 1. Males larger than females, largest male examined 38.7 mm SL, largest female 30.8 mm SL. Dorsal profile straight on head, slightly convex to convex from nape to the end of dorsal fin base. Ventral profile convex on head, slightly convex up to origin of anal fin base, straight along anal fin base. Caudal peduncle upper and lower profiles straight to slightly concave. Body slender, subcylindrical. Greatest body depth on vertical through pelvic fin base in males; slightly anterior, between vertical through pectoral fin base and vertical through pelvic fin origin, in females. Snout blunt, mouth superior, jaws short. Dorsal fin distal profile slightly pointed in males, rounded in females. Dorsal-fin origin at vertical through 11th to 12th anal-fin rays in males and through 10th to 11th anal-fin rays in females. Postero-median anal-fin rays longer than posterior and anterior rays, forming pointed tip of anal fin in males; anal-fin somehow rectangular in females. Caudal fin elliptical to subtruncate with short posterior ventral extension in males, becoming longer with the age (compare Figs. 2–3), rounded in females. Pectoral fin lanceolate, tip pointed and reaching middle portion of pelvic fin in males, tip rounded and not reaching vertical through pelvic-fin base in females. Pelvic fin lanceolate and short; tip pointed and reaching 3rd anal-fin ray in males; rounded to slightly pointed and reaching urogenital papillae in females. Dorsal-fin rays 9–10; anal-fin rays 14–16; caudal-fin rays 24–28; pectoralfin rays 17–18; pelvic-fin rays 7–8. Second proximal radial of dorsal fin between neural spines of 19th and 20th vertebrae, first proximal radial of anal fin between pleural ribs of 15th and 16th vertebrae; total vertebrae 30. Scales large, cycloid. Head fully scaled. Frontal squamation E-patterned. Body completely scaled with scales extending over caudal-fin base. No scales extending over other fins. Longitudinal series of scales 32–35 (with 4–6 on caudal fin); transverse series of scales 9–10; scale rows around caudal peduncle 17–18. Lateral line of trunk not complete. Two neuromasts on caudal fin base.
Coloration in life. Males (Figs 2–3). Side of body pale light reddish to light grey; dorsum darker, with black dots, venter white. Flanks and caudal peduncle with red to dark red vertical elongated dots arranged in irregular vertical rows, typically preceded, and some followed by a golden greenish vertically elongated thin dot. Humeral area yellowish golden with a dark red dot, hardly visible in some specimens (Figs. 1–2), well defined in others (Fig. 3). Head red to brownish; with two oblique postorbital yellow golden metallic irregular band, the first thinner, along the lower margin of eye and interrupted on anterior portion, the second broad and horizontally interrupted. Head ventrally white to pale grey. Iris golden yellow, with dark brown oblique bar crossing center of eye. Dorsal fin hyaline light brown with red to dark red dots, fused to form irregular, roughly horizontal lines. Anal fin hyaline, with light brown tint, and light blue iridescence on anteromedian portion. Basal portion light blue with vertically elongated red spots. Median and distal portion with irregular arranged red spots and dots, incomplete red rim. Caudal fin hyaline, with light red tint, dorsal portion with light blue reflection and black elongated spots and dots. Caudal-fin ventral portion extends posteriorly forming a small extension (“sword”), with pattern of horizontal stripes, broad orange stripe with black rim, turning yellow on distal portion; dorsally with a light blue narrow line. Some light blue iridescence above posterior portion of black rim. Pectoral fin hyaline, with light brown tint, light blue iridescence on basal portion, and red dots. Pelvic fin hyaline with light brown tint, light blue iridescence on basal-posterior portion, and few elongated red dots.
Females (Fig. 4). Overall color of body and head light greyish brown; dorsum darker, venter lighter. Dark reddish-brown dots irregularly arranged on flank, almost absent on anterior portion, mostly on posterior portion and caudal peduncle. Opercle with a golden to yellow metallic blotch, extending to above pectoral fin basis and on humeral region. Snout reddish. Iris yellow golden, with dark brown oblique bar crossing center of eye. Fins mostly hyaline; anal fin with four blue proximal spots.
Distribution and habitat notes. Known only from the type locality, a flooded area near the arroyo Crespo, belonging to Río San Martin drainage, a tributary of the Río Iténez, Río Madeira system, Amazon River basin, Bolivia (Fig. 5). At the time of collection of the type series, the type locality (Fig. 6) consisted in a flooded area, approximately 20 meters in diameter, and 0.1 to 0.2 meters deep, presenting muddy bottom with leaves and branches, brown, turbid still water with the following chemical-physical parameters (measured on late morning): conductivity: 7 µS, pH 5.6, and temperature 28°C. No other fish species were recorded.
Etymology. Named beltramonorum in honor to Christine and Jean Marc Beltramon, who discovered the species.
description: Published as part of Valdesalici, Stefano, 2023, A new annual killifish, Moema beltramonorum (Cyprinodontiformes: Rivulidae) from the Amazon basin, Bolivia, pp. 594-600 in Zootaxa 5383 (4) on pages 595-599, DOI: 10.11646/zootaxa.5383.4.10, http://zenodo.org/record/10369844