Taxonomic update of the flax family in Mexico Author González-Velasco, Juan 0000-0001-8743-3906 Departamento de Botánica, Colegio de Postgraduados. km 36.5 carretera México-Texcoco, Montecillo, 56230 Texcoco, Mexico, Mexico. & gonzalez. juan @ colpos. mx; https: // orcid. org / 0000 - 0001 - 8743 - 3906 gonzalez.juan@colpos.mx Author Burgos-Hernández, Mireya 0000-0003-3036-297X Departamento de Botánica, Colegio de Postgraduados. km 36.5 carretera México-Texcoco, Montecillo, 56230 Texcoco, Mexico, Mexico. & burgos. mireya @ colpos. mx; https: // orcid. org / 0000 - 0003 - 3036 - 297 X burgos.mireya@colpos.mx Author Galván-Escobedo, Iris G. 0000-0003-4250-4971 Departamento de Botánica, Colegio de Postgraduados. km 36.5 carretera México-Texcoco, Montecillo, 56230 Texcoco, Mexico, Mexico. & igalvan @ colpos. mx; https: // orcid. org / 0000 - 0003 - 4250 - 4971 igalvan@colpos.mx Author Castillo-Campos, Gonzalo 0000-0002-3059-8109 Red de Biodiversidad y Sistemática. Instituto de Ecología A. C. Carretera antigua a Coatepec km. 351, El Haya, 91073, Xalapa, Veracruz, Mexico. & gonzalo. castillo @ inecol. mx; https: // orcid. org / 0000 - 0002 - 3059 - 8109 gonzalo.castillo@inecol.mx text Phytotaxa 2022 2022-06-08 549 2 141 184 journal article 67684 10.11646/phytotaxa.549.2.3 62e44cf6-6f9d-4658-a89b-a0ddf687b5b9 1179-3163 6622753 Linum vernale Wooton (1898: 452) . ( Fig. 12 ). Type :— UNITED STATES OF AMERICA . New Mexico : Dona Ana Co. , Little Mountain , near Las Cruces, E.O . Wooton s.n ( holotype US!, isotype NY!) . Cathartolinum vernale Small (1907j: 80) . Mesynium vernale (Wooton) W.A.Weber (1984: 3) . Description: — Herbs , annual, 10–50 cm in height, glabrous, root thick; stems erect to ascending, slightly striate, branched at the base and inflorescences, glabrous. Leaves entire, alternate; basal leaves opposite, numerous in the lower part of the stem; linear, 8.0–17.0 × 0.5–1.3 mm , sessile, apex acute, whitish; 1-nerved, nerve most evident on the abaxial surface; scariose, glabrous, stipular glands present at the base. Inflorescence an open panicle, pedicels 2.0–12.0 mm long; bracts 3.4–6.6 mm long, glabrous, margin glandular-dentate, apex acute, whitish, stipular glands present at the base; sepals persistent, lanceolate, 4.0–7.5 × 1.3–1.6 mm , margin glandular-dentate; apex acute-acuminate, whitish; 1-nerved, stipular glands absent; petals yellow-orange to salmon, reddish base, widely obovate, 10.0–17.0 mm long, glabrous; stamens 4.0–8.0 mm long; anthers 1.0– 1.8 mm long, brown; staminodia absent; styles fused to near the apex, 4.0–8.0 mm long; stigmata capitate, dark red. Fruit ovoid, yellow, 3.0–4.0 × 2.5–3.2 mm , glabrous, pericarp thick, apex acute, dehiscent into 5 segments, false septa incomplete; seeds elliptical, reddish-brown, 2.0–2.8 × 0.9–1.3 mm . Distribution: — United States of America ; in Mexico , in Chihuahua , Coahuila , and Nuevo Leon ( Fig. 5c ). Habitat and ecology: —Yucca shrublands, thornless or sub-thornless small-leaved shrubland, and pine forests. Elevation 1200–2400 m . Limestone Cambisol, Phaeozem, Lithosol, Solonchak, and Xerosol soil types . Phenology :—Flowering and fruiting in March–September. Note: — Linum vernale has yellow-orange to salmon corollas, with a reddish base. This coloration facilitates recognizing the species. Besides, L. vernale is distinguished from other yellow-flowered species by the attachment of the styles and its dark-red anthers. Conservation status: —According to the criterion and subcriteria B established by the IUCN (2019) , L. vernale can be considered LC (EOO = 127,222.723 km 2 ), and although its AOO is 44 km 2 , it is known from> 10 localities. In addition, its distribution range reaches several localities outside the country. Specimens examined: — MEXICO . Chihuahua : Chihuahua , Parque Cumbres de Majalca , 2075 m , 02 August 1997 , C. Yen & E. Estrada 7699 ( ANSM !) ; Just below the high ridge-crests at the northwestern end of the Sierra del Diablo , 29 July 1941 , R.M. Stewart 1000 ( MEXU !) . Coahuila : General Cepeda , Sierra de La Paila , 1750 m , 25°38’00”N , 101°35’00”W , 27 April 1990 , J.A. Villarreal et al. 5586 ( ANSM !) ; Lampasos , 1.5 km al NE de La Mesa , 230 m , 20 March 1983 , O. Briones 1021 ( ANSM !) ; Lampasos , 1.5 km al NE de La Mesa , 230 m , 20 March 1983 , O. Briones 1069 ( ANSM !) ; Múzquiz , 5.70 km al sureste de las Esperanzas , 432 m , 27°42’31”N 101°18’20”W , 29 March 2015 , J.A. Encina et al. 5147 ( ANSM !) ; Ocampo , Sierra del Carmen , 1300 m , 28°47’00”N , 102°30’00”W , 27 March 1992 , M.A. Carranza et al. 1337 ( ANSM !) ; Rancho Vista Hermosa , 1458 m , 28°87’38”N, 102°60’29”W, 29 September 1997 , S. Wood et al. 97SW036 ( ANSM !) ; Valley extending northeast from Tanque Armendais to south end of Sierra del Pino , 19 August 1940 , I.M. Johnston & C.H. Muller 370 ( MEXU !) ; Zaragoza , Rancho Los Potros , Sierra El Burro , 1200 m , 28°55’00”N , 101°45’00”W , 14 July 1987 , D. Castillo-Quiroz 536 ( ANSM !) . Nuevo Leon : Los Ramones , La Presa , camino a la Hda. El Carrizo , 10 May 1979 , J.A. Villarreal 9526 ( ANSM !) ; Los Ramones , La Presa , camino a la Hda. El Carrizo , 10 May 1979 , J.A. Villarreal 9527 ( ANSM !) .