. .
. . .
. . . .
. . . . .
. . . . . .
. . . . .
. . . .
. . .
. .

sábado, julio 05, 2008


Abstract. Drymaria jenniferae is proposed as a new species. It appears to be related to the group "'Arenarioides" by the nature of the indumentum and the 2-8 lobed petals, but differs by its petals with four equal lobes, with the trunk (blade-like portion below lobes and above the basal claw) of each petal widened at the base. The species is notable for the absence of stipules, the cateniform trichomes, and the tuberculate seeds. A description, an illustration, and a key are provided. Key Words: Caryophyllaceae, Drymaria, Mexico.

Municipio de Viesca Coahuila, México

According to the most recent revision (Duke, 1961), the genus Drymaria Willd. ex Schult. (Caryophyllaceae) comprises 48 species mainly in subtropical areas of the Western Hemisphere; one species (Drymaria cordata Willd. ex Schult.) is widespread and occurs in Asia, Africa, Oceania, and Madagascar. The work of Duke (1961) includes a supra-specific classification in 17 series that were not validity published (Hartman, 2005) because they lacked Latin diagnoses and type citations. Since the revision of Duke, Turner (1995) described two new species from northeastern Mexico. Preliminary reports suggest there are 17 species and several infra-specific taxa in the Chihuahuan Desert (Hartman, in prep.). We here describe a new species of Drymaria from the southwestern Chihuahuan Desert Region.

Drymaria jenniferae Villarreal & A. E. Estrada, sp. nov. Type: Mexico. Coahuila: Mun. Viesca, E of Cinco de Mayo, 1600 m, 30 Sep 2006 (ft, ft), G. S. Hinton et al. 28498 (holotype: MEXU; isotypes: ANSM, ENCB, NY, TEX). (Fig. 1)

Drymariae axillari Brandegee similis sed differt petalis breviunguiculatis, doubus in 4 lobos equales bifurcatis, trunco (pars laminaris petalina sub lobis supraque unguem) ad basim leviter, stipulis carentibus, et seminibus lacrifonnibus tuberculatis.

Perennial herbs, the taproot woody, slender; stems originating from the root crown spreading or ascending, 4-8 cm long, branched, glaucous, indumentum hirsutulous, the trichomes septate, uniseriate, cateniform, often glandular. Leaves opposite; petioles 1- 3 mm long, glaucous, with same indumentum as the stems; blades elliptic to ovate, 4-10 x 3-6 mm, slightly succulent, the bases cuneate, decurrent to the petiole, the apices acute; stipules absent. Flowers solitary in distal branch axils; pedicels 3-6 mm long; sepals oblong to broadly elliptic, 4-5x1.8-2.2 mm, lobes, the lobes themselves divided into two cucullate, hirsutulous, the margins scarious, linear nearly equal lobes (each petal thus the apices obtuse; petals ca. 4 mm long, 4-lobed), the trunks (blade-like portion below white, divided half their length into two lobes and above claws) entire, slightly wider at the base, subhastate, the basal claw very short; staminodia absent; stamens 5, 2-3 mm long, the anthers ca. 1 mm long; ovaries ellipsoid, 1.0-1.5 mm long, glabrous, styles trifid, ca. 1 mm long. Capsules ellipsoid, 4— 6 mm long. Seeds 0.8 mm long, lacrimiform, glabrous, black, minutely roughened.

Distribution and ecology.—The species is known only from the type locality in southwestern Coahuila, growing in scattered sparse colonies on gypseous hillsides with only a few plants. The area was visited in 2007, but fertile material was unavailable due to drought. Other species in the area include Thymophylla setifolia Lag., Agave lechuguilla Torr., Fouquieria splendens Engelm., Euphorbia antisyphilitica Zucc, Anulocaulis erioselenus (A. Gray) Standi., Cyphomeris crassifolia (Standi.) Standi., Notholaena greggii (Kuhn) Maxon., Acacia crassifolia A. Gray, Tiquilia greggii (Torr. & A. Gray) A. Richardson, Tiquilia gossypina (Woot. & Standi.) A. Richardson, and Bursera schlechtendalii Engl.

Phenology.—Flowering August to October; fruiting in September and October, probably appearing after the rainy season.

Etymology.—The epithet honors Jennifer Hinton, great-granddaugther of George B. Hinton and a promising plant collector in the Hinton family, a family that has made tremendous contributions to the knowledge of the flora of Mexico (Hinton & Rzedowski, 1972).

The genus Drymaria was last revised by Duke (1961), but needs careful study by modern methods to evaluate Duke's informal classification (Hartman, 2005). Drymaria jenniferae does not fit comfortably within any of the infra-generic groups proposed by Duke (1961). It may be related to the complex of species that form the group "Arenarioides" (Duke, 1961), sharing with it the indumentum of glandular trichomes and petals with 2—8 lobes, each with a well-developed trunk, but it differs by the absence of stipules, the laterally denticulate petal trunks, and the granular or smooth seeds. It is morphologically close to Drymaria axillaris Brandegee but differs in having petals with four lobes and in the shape and surface of its seeds. It might also be compared with D. barkleyi Duke & Steyerm., because both taxa have petals with a wide trunk (slightly wider at the base and subhastate in D. jenniferae), a short claw, and lacrimiform, tuberculate seeds. The species in the group "Arenarioides" have deltoid stipules, while the new species seemingly lacks stipules. Drymaria arenarioides and D. axillaris have short glandular trichomes 0.25-0.4 mm long, with 1 or 2 septa, while D. jenniferae has trichomes 0.5-1.0 mm long, with 3—5 septa.

The four species can be separated by the following key:

1. Plants glabrous; petals 2 (or-3)-lobate, the trunks one-third as long as the lobes; inflorescences cymes D. barkleyi
1. Plants pubescent, the trichomes sometimes stipitate glandular; petals 2-4 -lobate, the
trunks as long as the lobes; inflorescences racemes or flowers axillary.
2. Leaves linear to oblong; inflorescences racemes D. arenarioides
2. Leaves ovate; flowers axillary.
3. Stipules present; petals 2-lobeted, the trunk bases not wider than apices; seeds
reticulate D. axillaris
3. Stipules absent; petals 4-lobated, the trunk bases wider than the apices, subhastate; seeds tuberculate D. jenniferae


We thank Guy Nesom for the Latin diagnosis and Miguel A. Carranza for preparing the illustration; George Diggs and Thomas Wendt for reviewing the English version; Billie L. Turner and Richard Spellenberg for the critical review of the manuscript.

Literature Cited

Duke, J. A. 1961. Preliminary revision of the genus Drymaria. Annals of the Missouri Botanical Garden 48: 173-268.

Hartman, R. L. In prep. In: Henrickson, J. & M. C. Johnston. A Flora of The Chihuahuan Desert Region. . 2005. Drymaria. In: Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico 12+ vols. New York and Oxford. Vol 5, pp. 9-14.

Hinton, J. & J. Rzedowski. 1972. George B. Hinton, collector of plants in southwestern Mexico. Journal of the Arnold Arboretum 53: 141-181.

Turner, B. L. 1995. Two new species of Drymaria (Caryophyllaceae) from gypseous soils in northern Nuevo Leon, Mexico. Phytologia 78: 199-203.

FIG. 1. Drymaria jenniferae. A. Whole plant. B. Leaf. C. Glandular septate trichome. D. Sepal. E. Petal with stamen. F. Seed. (Drawn from the holotype.)


No hay comentarios: