SEVEN NEW SPECIES AND ONE NEW VARIETY OF VALERIANA (VALERIANACEAE) FROM MEXICO

Seven new species of Valeriana endemic to Mexico are described and illustrated. Valeriana naidae Barrie is a suffrutescent, simple-leaved dioecious vine similar to V. subincisa Benth. Valeriana otomiana Barrie, V. zapotecana Barrie, V. chiapensis Barrie, V. moorei Barrie and V. rzedowskiorum Barrie are tap-rooted, perennial herbs. Valeriana tzotzilana Barrie is a biennial herb, endemic to Chiapas. The subspecies V. urticifolia var. scorpioides (DC.) Barrie is proposed, based on V. scorpioides DC. Additionally, a nomen novum, V. oaxacana Barrie, is proposed to replace the illegitimate name V. affinis M. Martens & Galeotti. A key to all species known to occur in Mexico is provided.

Valeriana (Valerianaceae) is a genus of approximately 350 species distributed throughout the Americas, Europe and Asia. Four species are endemic to Africa. Nearctic valerians are either rhizomatous or tap-rooted perennial herbs. In South America, home to roughly half the species in the genus, extensive morphological radiation has produced a broad range of herbs, shrubs and vines, including many highly specialized endemics of the paramo, puna and other high elevation, montane habitats.
Approximately 45 species of Valeriana are found in Mexico. These may be divided for descriptive purposes into three groups: biennial herbs, tap-rooted perennial herbs and herbaceous or suffrutescent vines. None of the rhizomatous herbs that comprise the majority of the valerian flora of the United States and Canada occur in Mexico with the exception of Valeriana arizonica A. Gray, which has been collected in northernmost Coahuila. A second predominately U.S. species, the tap-rooted Valeriana edulis Torrey & A. Gray, occurs sporadically at high elevations as far south as Cerro Potosi in Nuevo Leon, where it was collected above the timber line, at 3750 m. Most Mexican valerians are endemic; only a half-dozen species have ranges extending beyond its borders. Four are weedy species occuring as far south as Peru and Brazil. Two of these species are also found in the southernmost United States, Valeriana sorbifolia Kunth in southeastern Arizona and Valeriana scandens L. in central Florida.
Mexican valerians are characterized by having opposite, decussate leaves that are simple to pinnatifid or pinnately compound. The inflorescences are thyrsoid with cymose branches, the ultimate branches often scorpioid. Flowers may be hermaphroditic or unisexual, the plants hermaphroditic, gynodioecious or dioecious. Hermaphroditic flowers are protandrous, the style elongating and becoming receptive up to five days after the anthers have shed pollen. The calyx may be reduced or absent (in V. pulchella, V. pratensis and some individuals of V. apiifolia and V. deltoidea), but is more commonly present and pappus-like, involute in flower and spreading in fruit, with 6-25 plumose limbs, 2-8 mm long. The corolla is infundibular to salverform or rotate and typically gibbous at the base, that of pistillate flowers being 1/3 to 1/2 the size of perfect or male flowers, with five lobes, spreading or reflexed at anthesis. The three stamens are inserted on the corolla tube and are exserted to included in male-fertile flowers at anthesis. The single style is surmounted by a three-branched stigma. The fruit is an ovate, pyriform or elliptic cypsela with 3 veins on the abaxial side, 1 on the adaxial side, and 2 along the margins. Often overlooked, the relative positions of the veins on the fruit are a useful character for distinguishing species.
This paper describes seven new species and one new variety and proposes one nomen novum to replace an illegitimate name. A key to all species currently known to occur in Mexico is provided. Barrie, sp. nov Suffrutescent, dioecious, perennial vines, clambering over the canopies of shrubs and small trees, branches to 15 m long. Roots fibrous, becoming lignified with age. Stem terete; soft-woody below, grey, gnarled and much-branched; up to 2 cm in diameter; new growth herbaceous, green to purple-maculate; 2-6 mm in diameter; glabrous or with scattered pubescence, the hairs 0.2-0.4 mm long; pubescent to tomentose at the nodes, the hairs 0.5-0.8 mm long; with short branchlets, 5-20 mm long, bearing 2-5 leaf pairs, in the leaf axils along the main branches. Leaves simple, 2.0-12.5 cm long; the petioles 4-37 mm long, 0.5-2.0 mm wide, base connate, pubescent to tomentose, the hairs 0.2-0.7 mm long, commonly more densely vested toward the base; the blades 1.5-8.7 cm long, 0.8-4.1 cm wide; ovate to elliptic; base truncate or cuneate, rarely attenuate; apex acute; margin entire to irregularly denticulate; often with white, glandular patches every 5-8 mm; glabrous or ciliate, the hairs 0.3-0.7 mm long; surfaces glabrous to pubescent or tomentose, the hairs 0.2-0.4 mm long, the vestiture sometimes restricted to the veins below, or to the midvein abaxially and adaxially. Inflorescence paniculoid, diffuse, 5-10 cm long, 3-8 cm wide in early flower; 13-28 cm long, 10-25 cm wide in late flower or fruit; lateral branch pairs 1-5, the branches divaricate to ascending, 2-9 cm long; terminal branchlets scorpioid, with 3-6 flowers or fruits; glabrescent to tomentose, the vestiture commonly densest at the nodes. Bracts 1-32 mm long, 1-7 mm wide, linear to lanceolate, base free or connate, apex acute to acuminate, margins entire, ciliate, if only at the base, the hairs 0.2-0.4 mm long, surfaces glabrous or pubescent abaxially. Bractlets shorter than the fruits, 1.5-3.0 mm long, 0.4-0.8 mm wide, lanceolate, base free, apex acuminate, margins scarious, ciliate or glandular-ciliate, surfaces glabrous or pubescent abaxially. Calyx 10-13-fid, the limbs 3.5-5.5 mm long in fruit. Corollas white to pink or rose, the lobes often darker than the tube, rotate to infundibular, gibbous, glabrous or with scattered hairs without, 0.1-0.3 mm long, pilose within, the hairs 0.3-0.6 mm long; the corollas of males 1.8-3.6 mm long, the tube 1.1-2.4 mm long, 0.8-1.4 mm wide, the lobes 0.7-1.2 mm long, 0.5-1.1 mm wide, apices rounded, spreading to recurved at anthesis; corollas of females 1.1-1.9 mm long, the tube 0.6-1.2 mm long, the lobes 0.5-0.8 mm long, 0.4-0.6 mm wide, apices rounded, spreading or ascending at anthesis. Stamens weakly to strongly exserted, 0.7-1.7 mm long; the filaments 0.5-1.2 mm long, adnate for 2/5-2/3 of the length of the tube; the anthers 0.5-0.9 mm long. Style 1. Valeriana naidae belongs to a group of seven species of suffrutescent vines characterized by hollow, soft-woody stems and simple, ovate to lanceolate leaves. Four taxa are endemic to the Northern Andes, a fifth to Panama and Costa Rica. The sixth, V. subincisa Benth., occurs in Guatemala and southeastern Chiapas, and in the Sierra Madre Oriental from central Veracruz northward to Tamaulipas and Nuevo Leon and westward to Queretaro, at elevations above 1500 m. The northern populations are typically stoloniferous and decumbent, forming a loose ground cover on steep, shady slopes. In Guatemala and Chiapas, the species assumes the clambering habit of most members of this group, including V. naidae. The ranges of V. naidae and V. subincisa overlap in western Veracruz, in the regions around Mts. Orizaba and Cofre de Perote.

Valeriana naidae
Aside from growth form, V. naidae differs from V. subincisa in being dioecious, rather than gynodioecious, and its more diffuse paniculoid inflorescence with smaller flowers, the corollas about one-half the size of those of V. subincisa, 2-3.5 mm vs. 3-5.5 mm for male-fertile flowers, 1-1.5 mm vs. 2-3 mm for male-sterile flowers. The younger growth of Valeriana naidae also tends to be more pubescent.
Valeriana otomiana is dioecious, like V. laciniosa and V. zapotecana. It differs from the former in having coarser, less dissected, leaflets, larger female flowers (corollas 1.9-2.6 vs. 1.2-1.7 mm), smaller male flowers (corollas 2.5-3.5 vs. 3.0-4.1 mm) and smaller fruits (3.5-5 x 1.8-2.6 mm vs. 5.0-6.5 x 3.3-5.0 mm), and from the latter in having larger flowers and glabrous fruits. Both species are found in more xeric sites than V. otomiana. It also has been confused with V. albonervata, which has pubescent leaves with obovate or obtrullate leaflets, larger flowers and broader fruits.
Distribution: Dry limestone slopes in northwestern Hidalgo, in the mountain range west of Zimapán north to Jacala, 1600 m. Associated with Juniperus flaccida at the Jacala site.
Valeriana moorei is most distinctive for its compound leaves with the marked, hispidulous lower veins. The large, predominantly basal, compound leaves and stout taproot suggest a possible relationship with the members of series Ceratophyllae. However, V. moorei lacks leaflet appendages, the pilose collar within the corolla and the carinate fruits. The stout caudex bearing old leaf bases suggest a possible relationship between this species and V. cucurbitifolia of Chiapas and Oaxaca. The overall shape of the leaflets and of the fruits support this as well.
This species is known from only two collections. The plants of the type collection are in bud and early flower. The leaves are well developed, but small (10-18 cm long). The paratype is a much more mature specimen with a fully expanded inflorescence and much larger leaves (35-42 cm long). None of the specimens is female and it may be that the species is hermaphroditic. However, the lack of female specimens may be an artifact of too few collections.
Both collections of V. moorei have been made in the "matorral de Juniperus flaccida" (Rzedowski, 1978), a transition zone between the wetter pine-oak zone of higher elevations, and the more xeric habitats below.

Valeriana urticifolia
A widespread species distinguished from other biennial valerians, with the exception of V. selerorum, by the simple dentate leaves. Valeriana selerorum differs in its rhombic or trullate fruits and inflorescence which is always paniculoid. The two differ in leaf venation as well; the veins of V. urticifolia are straight, while those of V. selerorum tend to be more arcuate. The range of V. selerorum is relatively small, northeastern Michoacan and southwestern Mexico, and within the range of V. urticifolia var. scorpioides and it is not uncommon to find the two growing together. Where they do, V. urticifolia has lavender flowers, which set it off from the white or pale pink flowered V. selerorum.
The two varieties of V. urticifolia are recognized here may be separated by fruit characters alone. Leaves ovate to widely ovate, reniform or triangular. Inflorescence paniculoid. Corollas white or pale pink; corollas of hermaphrodites 2.8-6.7 mm long, the tube 1.5-5.2 mm long, 0.3-0.7 mm wide, the lobes 0.9-2.2 mm long, 0.3-0.6 mm wide; corollas of females 2.2-3.4 mm long, the tube 1.1-2.5 mm long, 0.3-0.5 mm wide, the lobes 0.7-1.4 mm long, 0.5-0.9 mm wide. Cypsela tan or purple maculate, 1.6-2.2 mm long, 1.0-1.5 mm wide, the midveins slightly reinforced, the abaxial lateral veins reinforced at the margins, producing a margin thicker than the body of the fruit. Chromosome number n = 16 (Barrie 1041, TEX). Variety urticifola is most obviously typified by the fruits. Corolla color may also be a useful distinguishing character, being white or nearly so in this variety and lavender in var. scorpioides, though white corollas occur in some populations of it as well.
Distribution: The Sierra Madre Occidental from southern Chihuahua to Jalisco, across the Sierra Volcanica Transversal to the Orizaba region of Veracruz. Two collections known from Guatemala. As with var. urticifolia, this is a weedy species of the pine-oak zone. Valeriana urticifolia var. scorpioides is distinguished by the fruits and, in many populations, the lavender flowers. Rhombic-leaved individuals, a rarity in var. urticifolia, can be common, especially in the northern states. Like var. urticifolia, it is often found growing with other weedy biennial valerians.
There is a broad band along which the two varieties intergrade, stretching from Nayarit on the west through Jalisco and Michoacan, as far east as Pico de Orizaba, Veracruz. Populations in this region may have the fruits of one variety and the flowers of the other, or fruits in which the development and positioning of the lateral veins is intermediate. In the populations that I have observed in the field in Michoacan and Jalisco, the typical varietal forms do not occur in the same populations with the intermediates. As one moves north or south, away from this zone, the typical varieties emerge.