Phoxinusbigerri Kottelat, 2007

(Fig. 4)

Phoxinusbigerri Kottelat, 2007: 146, fig. 2 (type local- ity: Adour River in Tarbes (Séméac)).

Material examined

MNHN 2006-1703, holotype, f, 59.1 mm SL; France: Adour River, Tarbes, 43°13.7’N, 0°05.5’E, alt. 316 m. MNHN 2006-1704, paratypes, 2 m, 2 f, 40.9-57.2 mm SL; France: Adour River, Tarbes, 43°13.7’N, 0°05.5’E; alt. 316 m. MNHN 2014-2741, 1 m, 3 f, 52.5-63.6 mm SL; France: Louts Stream, Samadet, 43°37.5’N, 0°29.3’W, alt. 136 m. MNHN 2014-2755, 2 m, 4 f, 46.3-58.2 mm SL; France: Adour River, Estirac, 43°30.2’N, 0°01.8’E, alt. 165 m. MNHN 2014-2756, 6 m, 5 f, 42.4-57.0 mm SL; France: Lausset Stream, Cheraute, 43°14.8’N, 0°47.5’W, alt. 173 m. MNHN 2014-2749, 13, 44.0-55.4 mm SL; Bayse Stream, Aubertin, 46°15.8’N, 0°29.9’W, alt. 155 m .

Material used for molecular analysis

MNHN 2010-0487, 1, tag 4092; France: Adour River, Tarbes, 43°13.9’N, 0°05.3’E, alt. 315 m. (COI: GenBank accession number: MT975755, 12S: GenBank accession number: MT975345) . MNHN 2010-0508, 1, tag 4120; France: Canal de Branc, Juillan, 43°12.1’N, 0°01.4’E, alt. 328 m. (COI: GenBankaccessionnumber: MT975761) . MNHN 2010-0481, 1, tag 4096; France: Echez Stream, Lar- reule, 43°26.7’N, 0°01.7’E, alt. 186 m. (COI: GenBank accession number: MT975756, 12S: GenBank accession number: MT975376) . MNHN 2011-0938, 1, tag 10771; France: Gave d’Aspe, Osse-en-Aspe, 43°00.7’N, 0°36.2’W, alt. 391 m. (COI: GenBankaccessionnumber: MT975706) . MNHN 2011- 0940, 1, tag 10770; France: Gave de Pau, Assat, 43°14.3’N, 0°18.4’W, alt. 214 m. (COI: GenBankaccessionnumber: MT975705) . MNHN 2014-2756, 2, tag 1987 and 1988; France: Lausset Stream, Cheraute, 43°14.8’N, 0°47.5’W, alt. 173 m. (COI: GenBank accession numbers: MT975743, MT975744) . MNHN 2010-1024, 1, tag 4196; France: Luy Stream, Saugnac-et-Cambran, 43°43.6’N, 1°00.7’W, alt. 7 m. (COI: GenBankaccessionnumber: MT975767, 12S: Gen- Bank accession number: MT975380) . MNHN 2013-0622, 2, tag 10945 and 10946; France: Nive d’Arneguy, Uhart-cize, 43°10.1’N, 1°14.8’W, alt. 154 m. (COI: GenBank accession numbers: MT975717, MT975718) . MNHN 2011-0262, 1, tag 4369; France: brook of Cabanes, 43°44.3’N, 1°02.5’W, alt. 14 m. (COI: GenBankaccessionnumber: MT975784, 12S: GenBankaccessionnumber: MT975388) . MNHN 2010-1033, 1, tag 4210; France: Saison Stream, Menditte, 43°09.7’N, 0°53.8’W, alt. 177 m. (COI: GenBankaccessionnumber: MT975770) . MNHN 2011-0928, 1, tag 10787; France: Rim- bez Stream, Saint-Pe-Saint-Simon, 44°01.1’N, 0°03.7’E, alt. 109 m. (COI: GenBankaccessionnumber: MT975711) .

Diagnosis

Phoxinus bigerri is distinguished from the other French Phoxinus species by its unique nuptial colour pattern. The male is diagnosed by having bold, black bars of variable widths crossing Z2 to Z4 (vs. bars only crossing Z2), no stripe on Z3 (vs. present), Z2 to Z4 golden-yellow between bars (vs. pale brownish), Z5 and belly greyish to black (vs. Z5 silvery, white or red on belly), orange pectoral, pelvic and anal fins (Fig. 4A, C) (vs. yellow). Female with long black bars on the flank (vs. a black or brown stripe along Z3), interspaces between flank-bars greyish along Z2 to Z4 (vs. silvery, greenish or yellowish), and pectoral, pelvic and anal fin bases red (Fig. 4B, D) (vs. pinkish).

Phoxinus biggeri is further distinguished from some other species as detailed below by having 68-87 scales along the lateral series (vs. 72-99), snout very stout (vs. slightly pointed), mouth terminal or slightly subterminal (vs. subterminal), analfinmarginstraighttoconvex (vs. straight to slightly concave), and depth of caudal peduncle 2.1-3.4 times in its length (vs. 2.5-4.6).

Nuptial colouration

Male. – Snout and top of head dark greyish to black. A black bar on operculum reaching from top of head to suboperculum. Cheeks white or greyish. Operculum with a white spot at uppermost, posterior corner followed by a yellow spot on lower part. Z1 black. Flank with black bars of variable widths. Z2 to Z4 golden-yellow. Z5 and belly greyish to black. Mouth pinkish. Pectoral, pelvic and anal fin orange (Fig. 4A, C).

Female. – Black flank bars reaching from Z2 to Z4, inter- spaces greyish, and pectoral, pelvic and anal fin bases red (Fig. 4B, D).

Molecular characterization

On the COI marker, P. bigerri has nine diagnostic sites, including seven synapomorphies (Tab. III). For the 12S rDNA marker, seven diagnostic sites characterise this species: G (vs. A) in position 25, T (vs. G) in position 403, C (vs. A) in position 577, G (vs. A) in position 596, T (vs. C) in position 881, T (vs. C) in position 882 and C (vs. T) in position 889.

Distribution

In France, P. bigerri is native to the Adour and the Leyre drainages (Fig. 1). It is introduced in the Aude catchment as well as some tributaries of the Garonne drainage adjacent to the Adour by anglers as trout bait. In Spain, it is native to the Ebro drainage and the eastern Cantabria region, and was introduced in Galicia and the Duero drainages (Corral-Lou et al., 2019; Garcia-Raventós et al., 2020).

Vernacular name

Adour minnow (English), Vairon basque (French).

Remarks

Kottelat (2007) described this species as having usually a complete lateral line. Our examination confirms that some individuals have a com- plete lateral line but most individuals examined by us, have an incomplete lateral line, reaching just to or slightly beyond the anal fin base.