Phoxinus dragarum, Denys & Dettai & Persat & Daszkiewicz & Hautecoeur & Keith, 2020

Denys, Gaël P. J., Dettai, Agnès, Persat, Henri, Daszkiewicz, Piotr, Hautecoeur, Mélyne & Keith, Philippe, 2020, Revision of Phoxinus in France with the description of two new species (Teleostei, Leuciscidae), Cybium 44 (3), pp. 205-237 : 220-223

Phoxinus dragarum , new species

( Fig. 8 )

Holotype

MNHN 2019-0262 , Ơ, 49.5 mm SL; France: Arrat-Devant Stream , Manent-Montané, 43°20.7’N, 0°37.5’E, alt. 275 m.

Paratypes

MNHN 2014-2725 , 5 Ơ, 18 ♀, 44.9-61.2 mm SL; France: Arrat-Devant Stream , Manent-Montané, 43°20.7’N, 0°37.5’E . MNHN 2014-2813 , 2 Ơ, 4 ♀, 49.3-57.5 mm SL; France: Ciron Stream , Escaudes, 44°19.2’N, 0°11.4’W, alt. 76 m. MNHN 2014-2807 , 1 ♀, 62.7 mm SL; France: Couze Stream , Bayac, 44°48.3’N, 0°43.8’E, alt. 64 m. MNHN 2014-2735 , 1 Ơ, 6 ♀, 43.6-60.8 mm SL; France: Thèze Stream , Montcabrier, 44°32.4’N, 1°03.9’E, alt. 123 m. MNHN 2014-2738 , 3 Ơ, 45.5-51.9 mm SL; France: Vère Stream , Cahuzac-sur-Vère, 43°59.2’N, 1°53.7’E, alt. 189 m. Additional material

MNHN 2014-2761 , 3 ♀, 44.7-53.7 mm SL; France: Dronne Stream , Bourdeilles, 45°19.4’N, 0°35.1’E, alt. 94 m. MNHN 2014-2759 , 4 ♀, 57.6-66.5 mm SL; France: Dropt Stream , Gaugeac, 44°39.7’N, 0°52.5’E, alt. 134 m. MNHN 2014-2731 , 4 ♀, 51.0- 57.6 mm SL; France: Volp Stream , Montesquieu-Avantès, 43°02.7’N, 1°11.2’E, alt. 451 m.

Material used for molecular analysis

MNHN 2019-0262 , holotype, tag 12470; France: Arrat-Devant Stream , Manent-Montané, 43°20.7’N, 0°37.5’E, alt. 275 m. (COI: GenBank accession number: MT975386, 12S: GenBank accession number: MT975361) . MNHN 2014 - 2813, paratypes, 2, tag 1989 and 1990; France: Ciron Stream , Escaudes, 44°19.2’N, 0°11.4’W, alt. 76 m. (COI: Gen-Bank accession numbers: MT975361, MT975746). MNHN 2014-2738 , paratype, 2, tag 12342 and 12343; France: Vère Stream , Cahuzac-sur-Vère, 43°59.2’N, 1°53.7’E, alt. 189 m. (COI: GenBank accession number: MT975720, 12S: GenBank accession numbers: MT975353, MT975354). MNHN 2011-0933 , 1 , tag 10781; France: Avance Stream , Montpouillan, 44°28.1’N, 0°07.6’E, alt. 25 m. (COI: Gen-Bank accession number: MT975709, 12S: GenBank accession number: MT975350). MNHN 2011-0937 , 1 , tag 10778; France: Boralde de Flaujac Stream , Espalion, 44°32’N, 2°47.5’E, alt. 386 m. (COI: GenBank accession number: MT975708). MNHN 2010-0491 , 1 , tag 4103; France: Douctouyre Stream , Dun, 43°02.3’N, 1°47.6’E, alt. 321 m. (COI: GenBank accession number: MT975757). MNHN 2011- 0416 , 1 , tag 4427; France: Doustre Stream , Saint-Bazilede-la-Roche, 45°08.5’N, 1°57.6’E, alt. 525 m. (COI: Gen-Bank accession number: MT975793). MNHN 2010-0513 , 1 , tag 4124; France: Job Stream , Lespiteau, 43°04.1’N, 0°45.5’E, alt. 367 m. (COI: GenBank accession number: MT975762). MNHN 2011-0278 , 2 , tag 4390 and 4391; France: Pique Stream , Cierp-Gaud, 42°54.7’N, 0°03.8’E, alt. 493 m. (COI: GenBank accession numbers: MT975787, MT975788). MNHN 2011-0928 , 1 , tag 10786 and 10787; France: Rimbez Stream , Saint-Pe-Saint-Simon, 44°01.1’N, 0°03.7’E, alt. 109 m. (COI: GenBank accession number: MT975710, 12S: GenBank accession numbers: MT975351, MT975352). MNHN 2010-0504 , 1 , tag 4116; France: Salat Stream , Rivèrenert, 42°57.4’N, 1°10.6’E, alt. 412 m. (COI: GenBank accession number: MT975760, 12S: GenBank accession number: MT975378). MNHN 2010-0476 , 1 , tag 4031; France: Triouzoune Stream , Saint-Angel, 45°30.2’N, 2°14.1’E, alt. 637 m. (COI: GenBank accession number: MT975753). MNHN 2011-1570 , 2 , tag 10931 and 10932; France: Tavignano River , Piedicorte-di-Gaccio, 42°12.8’N, 9°18.8’E, alt. 153 m. (COI: GenBank accession numbers: MT975715, MT975716) .

Diagnosis

Phoxinus dragarum is distinguished from the other French Phoxinus species by its unique nuptial colour pattern. The male has a green stripe in Z3 reaching anal fin base (vs. stripe black or absent), and greenish yellow Z4 ( Fig. 8B, D ) (vs. green or golden yellow). The female has a green-ochre colouration in Z4 (vs. yellow, green, greyish or white), and a black line in Z5 from pectoral fin bases to anal fin base ( Fig. 8C, E ) (vs. absence of black line).

Phoxinus dragarum is further distinguished from P. bigerri by having 50-74 pored scales (vs. 68-87), a slightly stout snout (vs. very stout), and a straight to slightly concave anal fin margin (vs. straight to convex). It is further distinguished from P. csikii by having a snout slightly stout (vs. very stout and blunt), and a straight to slightly concave anal fin margin (vs. straight to slightly convex). The new species is further distinguished from P. phoxinus by having an incomplete lateral line usually reaching anal fin base or just after the last ray (vs. reaching to caudal peduncle), and a slightly stout snout (vs. slightly pointed).

Phoxinus dragarum is further distinguished from P. septimaniae by having an incomplete lateral line usually reaching anal fin base or just after the last ray (vs. reaching caudal peduncle or almost complete), 50-74 pored scales (vs. 73-86), a slightly stout snout (vs. slightly pointed), and 2 scaled patches at the pectoral fin bases separated by an unscaled area (vs. scaled breath between the pectoral fin bases in some populations).

The nuptial male P. dragarum is further distinguished by having a red belly, the red colour ending before the caudal peduncle (vs. belly greyish to black in P. bigerri ; red belly extending to the caudal peduncle in P. csikii ; belly pinkish to light orange in P. phoxinus ; white in P. septimaniae ), lacking a yellow dot between the mouth and the eye (vs. presence in P. septimaniae ), having red lips (vs. pinkish in P. bigerri and P. phoxinus ), yellow pectoral, pelvic and anal fins (vs. orange in P. bigerri ; yellow-orange pectoral fin with a red disc at the interior side in P. septimaniae ), and red pectoral, pelvic and anal fins bases (vs. pinkish in P. bigerri and P. phoxinus ). The nuptial female is further distinguished by having a black stripe along Z3 (vs. no stripe in P. bigerri ), a black Z5 (vs. white in P. bigerri and P. csikii ), a pale yellow spot on the operculum (vs. absence in P. bigerri ; marked yellow in P. phoxinus ), and pale yellow pectoral fin (vs. marked yellow in P. phoxinus ).

Description

Morphometric data is shown in table IV. Largest examined specimen 66.5 mm SL. Body moderately elongate, dorsal and ventral profile about symmetric or ventral profile slightly more convex. Dorsal profile of head markedly more convex than ventral one. Caudal peduncle length 2.3- 3.5 times in depth of caudal peduncle. Snout slightly stout. Mouth terminal or slightly subterminal, upper lip and snout not projecting beyond tip of lower jaw. Tip of upper lip at level or above level of lowest point of eye. In lateral view, eye not or almost flushed with dorsal profile. No supraorbital ridge.

Dorsal fin with 3 simple and 6½-8½ branched rays. Distal dorsal fin margin markedly convex, second branched ray longest, dorsal fin origin behind vertical of pelvic fin origin. Pectoral fin with 1 simple and 13-18 branched rays (10 for one specimen; usually 14-15), reaching to pelvic fin origin in male, not reaching it in female. Pelvic fin with 1 simple and 5-8 branched rays (usually 7-8), reaching slightly beyond anal fin origin in male, not reaching in female. Anal fin with 3 simple and 6½-8½ branched rays. Anal fin origin slightly in front of vertical through insertion of dorsal fin or behind. Anal fin margin straight to slightly concave, second branched ray longest.

Lateral line incomplete usually reaching to vertical of dorsal-fin base or to vertical of base of last anal fin ray. 70-97 lateral scales, including 50-74 pored scales. Two scaled patches at pectoral fin insertions separated by an unscaled area. No scales between pectoral fin bases. Nuptial tubercles observed in both sexes.

Nuptial colouration

Male. – Snout and top of head dark-brown. A black bar on operculum reaching from top of head to branchiostegal rays. Cheeks white. Operculum with a white spot at uppermost, posterior corner. A yellow spot on suboperculum. Lips red. Z1 brown to black. Z2 pale brown. Black vermiculations in Z1 to Z2. Z3 green. Z4 yellow or yellowish-green. A black line along Z5 from pectoral fin origin to caudal peduncle. Belly red, red couloration not extending to caudal peduncle. Fins yellow-orange. ( Fig. 8B, D ).

Female. – Z3 with a black stripe. Z4 green-ochre until anal fin. A black line along Z5 from pectoral fin origin to caudal peduncle. Pinkish tinge visible at base of pectoral, pelvic and anal fins and on mouth. Belly white. White and yellow spots on operculum and white spots at origin of pectoral, pelvic and anal fins ( Fig. 8C, E ).

Colouration in preservation

Dark bars remain after preservation in ethanol. Green colouration turns to dark grey, yellow and red colourations faded and usually absent ( Fig. 8A ).

Molecular characterization

On the COI marker, P. dragarum has six diagnostic sites, including two synapomorphies. However, the Garonne and Dordogne populations are characterised both by three diagnostic sites (Tab. II). For the 12S rDNA marker, five diagnostic sites characterise this species: G (vs. A) in position 179, A (vs. G) in position 307, T (vs. A or G) in position 310, C (vs. A or G) in position 412 and A (vs. G) in position 478.

Distribution

This species is endemic to the Garonne drainage ( Fig. 1 ). It has been introduced to Spain, in the Ebro drainage along the Pyrenean side ( Corral-Lou et al., 2019) and also in the Guadalquivir drainage ( Sáez-Gómez and Prenda, 2019: fig. 2).

Ecology

Phoxinus dragarum is abundant in the barbel zone ( Ibarra et al., 2005). It is usually found in headwater streams ( Ibarra et al., 2005; Santoul et al., 2005) with a low slope in altitude and a high fish species richness ( Céréghino et al., 2005). It is often found in sympatry with Gobio occitaniae Kottelat & Persat, 2005 ( Céréghino et al., 2005). Studies made on populations from the stream Ariège and the Garonne River demonstrated that P. dragarum prefers shallow water located along the bank, with no or low velocity and a mixed substrate (pebbles, gravel, sand and sludge) ( Mastrorillo et al., 1996, 1997; Reyjol et al., 2001). Intraspecific variations of functional traits (such as body mass, metabolic rate, excretion rate and boldness) were observed within several populations due to local adaptations to water temperature or predation pressure, or co-variations driven by genetic drift ( Raffard et al., 2019). The spawning season occurs from April to May, June in higher altitude (Denys, pers. obs., 2014).

Etymology

The species name dragarum is the genitive of a latinized name “dragas” which are fairies from of the Occitan folklore. Dragas are the companions of the Drac, a kind of dragon living in the streams of the Ariège department (Garonne drainage). In the land of Foix, these melusian serpentiform fairies attack intruders crossing their territory. The sound of bells alone can stop them. They come out only to wash their clothes with a gold beater, not without having closely watched the area with their only eye in the middle of the forehead ( Ely and Tsaag Valren, 2013).

Vernacular name

Garonne minnow (English), Vairon de la Garonne (French).

Remarks

The Garonne and Dordogne clades are separated by a divergence of 1.6%. As we find no other character states distinguishing both population groups, we consider them as two evolutionary lineages of a same species.

Figures

Figure 1. – Records of Phoxinus used in this study. Coloured squares repre- sent the six species delineated in this study: P. phoxinus (blue), P. bigerri (red), P. csikii (green), P. septimaniae (yellow), P. dragarum (purple), and P. fayollarum (orange).

Figure 8. – Phoxinus dragarum Holotype Ơ (A), 49.52 mm SL from the Arrat-Devant Stream, Manent-Montané 43°20.7’N, 0°37.5’E, MNHN 2019-0262; paratypes Ơ (B) and ♀ (C), same location as holotype, MNHN 2014-2725; nuptial colouration pattern for male (D) and female (E).