New Species of Scutellaria (Lamiaceae) from the Chihuahuan Desert Region

Three new species of Scutellaria are described from the Chihuahuan Desert Region of Mexico: S. hintoniorum from western Nuevo Leon, S. wendtii from eastern Chihuahua, and S. carmenensis from northern Coahuila.


INTRODUCTION
Studies in connection with the Flora of the Chihuahuan Desert Region project have revealed new taxa within Scutellaria.
Rhizomatous, colonial, gypsophilous perennials 1-1.5 dm tall forming small rounded-spreading plants 1-3.5 dm wide; lower stems spreading then erect-ascending; young stems yellow-green to maroonish, densely hirtellous with spreading, rarely slightly ascending hairs 0.06-0.15mm long; internodes 1-5 mm long.Leaves crowded, overlapping, ascending; leaf blades broadly obovate, suborbicular to oblanceolate, broadly elliptical or elliptical, (3.5-)5.5-8.5 mm long, 3.3-6.5 mm.wide, rounded to obtuse at the tip, broadly cuneate with margins tapering to a winged petiole 1-2 mm long at the base, entire, conduplicate, yellowish green, softly strigose with geniculate antrorse hairs 0.2-0.3mm long and with yellow sessile glands, thick, the mid and secondary veins slightly raised beneath, impressed above.Flowers paired at upper nodes (1 per leaf axil); peduncles 0-1.2 mm long; bracteoles subulate, 0.5-1.1 mm long; pedicels 2.5-6 mm long, thickish, all vestitured as the young stems, often maroon; calyces 4.5-6 mm long, the lower lip entire, to 7 mm long in fruit, the upper lip with a crest 1-2(-3) mm high, the calyx yellow-green or tinged with maroon, hirtellous and with sessile glands throughout; corollas scarlet-deep red, ascending, 21-27 mm long, the tube curved upward at the base, 16-23 mm long, slightly ampliate, to 3.8-5 mm wide at the throat (pressed), the anterior lobe deflexed, 3.5-6 mm long and nearly as wide, retuse, with the margins reflexing, the upper lobe somewhat galeate, 5-6 mm long, the terminal lobe retuse, 2-3.5 mm long, covering the anthers and style, the marginal lobes 4-5 mm long, 1-2 mm wide, these reflexed, the corolla villous outside with red-septate, spreading hairs 0.4-0.5 mm long, glabrous inside except for a dense villous band ofhairs 2-3 mm thick just above the base and with less dense hairs near the anthers; stamens 4, the anterior free filaments 10-12 mm long, the posterior free filaments about 4-6 mm long, both locally villous, yellowish, recurved at the very tip presenting the anthers around the stigma inside the more or less galeate upper corolla lobe; anthers yellowish or purplish, 0.6-0.7 mm long, 0.8-0.9mm wide, with dense aggregations of globose glands on both sides, the suture margins densely ciliate-hirtellous, the anterior more distal anthers with only 1 anther sac, the posterior anthers with 2 anther sacs; style glabrous, broadening at tip.Nutlets subglobose, black, 1.4-1.5 rom long and wide, densely tuberculate with about 9 tubercules per 1 rom of surface, the tubercules each terminating in an array of trichomes.Hess 18951 (TEX and to be distributed).
The new species appears most closely related to S. suffrutescence S. Wats of Epling's (1942) sect.Spinosae Epling characterized by its twiggy, rigid habit and red corollas.Scutellaria suffrutescence occurs on nongypsum sites in eastern Coahuila, western Nuevo Leon and adjacent Tamaulipas.Both have woody stems, scarlet, ascending flowers, geniculate hairs on similarly small leaves, hairs on the nutlet tubercules.Scutellaria suffrutescence has shorter calyces 3-4 rom long, a more shrubby, twiggy, divaricately branched habit with slender stems, lacks rhizomes and is considerably more variable in vestiture.

Scutellaria wendtii
Low spreading, intricately, divaricately branched, calcicolous subshrubs 5-15 em tall and much broader from a deep woody caudex, the old flowering branches persisting as thorns; young stems yellowish green, incompletely but often densely hirtellous-canescent with stout, mostly geniculately decurved hairs under 0.03-0.1 rom long, also with sessile, yellow glands; internodes 8-13 rom long; leaves ascending; leaf blades oblong-ovate to ovate, 2.5-7(-10) rom long, 1.5-6(-7.5)rom wide, rounded to obtuse at the tip, mostly rounded to subcordate above petioles 0.5-2 rom long at the base, entire, dark green, dark green drying yellowish green, very sparsely puberulent with hairs to 0.1 rom long and with sessile, yellow glands on both surfaces, moderately thickened, only the mid vein slightly depressed above, the mid vein and secondary veins slightly raised, yellowish beneath.Flowers paired at upper nodes (1 per leaf axil); peduncles 0.4-0.7 rom long; bracteoles subulate, 0.3--0.5 rom long; pedicles 2-2.5 rom long, incompletely canescent; calyces 2-2.5 rom long (to 3.5 rom long in fruit), the lower lip to 3.5-4 rom long in fruit, the upper lip with a crest 1-1.5 rom high, 1.5 rom wide, the calyces yellow-green, often marked with maroon, very sparsely puberulent and with large yellow glands throughout; corollas bluish purple with a yellow area marked with blue dots on the lower lip and throat, 10-15 mm long, the tube sigmoidly curved, 6-10 mm long, slightly ampliate and to 1.5 mm broad (2.5 mm pressed) at the throat, the anterior lobe spreading-deflexed, broadly ovate, 3.5-5.5 mm long, retuse with a terminal notch to 1 mm deep, the margins reflexing, entire to erose, with a pair of raised ridges 2 mm long separated by a medial groove that extends into the tube, the upper lobe somewhat galeate, bent forward, 3.3-5.5 mm long, the terminal lobe emarginate, the lateral lobes shallow, 3 mm long, their margins reflexed backwards, the corolla villous outside with septate, spreading hairs 0.2-0.3mm long, glabrous within except for a very densely villous zone 2-3 mm thick at the level of the calyx tube; stamens 4, the anterior free filaments 7-9 mm long, the posterior free filaments 2.5-4.5 mm long, both filaments mostly glabrous, partially villous, white to blue where exposed, recurved at the very tip; anthers whitish, 0.5-0.6 mm long, 0. 7-0.8 mm wide, with aggregations of globose glands on each side, the suture margins densely ciliate-hirtellous, the anterior more distal anthers with only 1 anther sac, the posterior anthers with 2 anther sacs; style glabrous, the upper lobe not developed, slightly exserted.Nutlets obovoid, 0.9-1 mm long, black, tuberculate, tips of tubercules with an array of short conical hairs under 0.1 mm long.
In its twiggy habit S. wendtii appears most similar to S. suffrutescence, but the former is a much smaller plant, has smaller, bluish (not deep red) corollas, smaller calyces, and a tighter, though similar, vegetative vestiture and lacks stipitate glands on calyces, corollas and inflorescences.It, however, appears to be allied to species of sect.Spinosae based on growth habit, the hairs on the nutlet tubercles and other features.The species is named for Thomas L. Wendt, who first collected this species during forays in the Chihuahuan Desert with Marshall C. Johnston and Fernando Chiang.Henrickson,sp. nov. Fig. 3 Differet a Scutellaria parvulae seminum morphologia, a S. tuberosae foliis integris, petiolis brevioribus, et vestimento breviore, a specius S. sect.resinosae a rhizomatibus gracilibus.

Scutellaria carmenensis
Rhizomatous, colonial perennial herbs 1-2 dm tall; stems erect-ascending above often decumbent bases, green to purple; young stems sericeous-strigose with soft, strongly, geniculate to slightly decurved, slender, uniseriate hairs 0.15-0.3(-0.6)mm long, these mixed with scattered or rarely dense erect slender gland-tipped hairs 0.3-0.7 mm long in the lower third of the plant; internodes 7-25 mm long.Leaves with narrowly winged petioles 1-3 mm long; leaf blades ovate to oblongovate, 8-15(-20) mm long, 2.5-8(-11) mm wide, rounded to obtuse at the tip, broadly cuneate to rounded at the base, the margins entire or in larger leaves crenate, softly villous-strigose along the main veins and margins or throughout with decurved soft, tapering hairs 0.1-0.2(-0.4)mm long, these often more dense along the margins, the lower leaves progressively more pilose and with stipitate glands 0.3-0.5(-0.8)mm long along the veins and margins, or on the lowermost leaves throughout, both leaf surfaces with sessile glands.Flowers paired in mid to upper nodes (1 per leaf axil); pedicels 2-4 mm long, ebracteolate; flowering calyces 4.2-5 mm long with decurved hairs 0.1-0.3mm long and scattered sessile glands; corollas purple-blue with white on the base of the tube and on the lower lip where spotted with blue, (17-)20-25 mm long, the tube curved at the base, ampliate, 11-15(-17) mm long, to 4-5.5 mm wide at throat (pressed); anterior lobe spreading-deflexed, broadly oblong, 7-10 mm long, notched at the tip, often erose and with a deep marginal notch about halfway to base; the galeate posterior lobe 5-5.5 mm long, with the terminal lobe 2.5-3 mm long and covering the anthers, the marginal lobes 3-4 mm long, reflexed marginally, the tube, throat and mid portion of the galea sparsely villous inside with hairs to 0. 7 mm long, densely villous with uniseriate hairs 0.2-0.6(-0.9)mm long outside; stamens 4, the anterior free filaments 11-12 mm long, the posterior free filaments 4-5.5 mm long, both curved at the tip and sparsely villous with hairs 0.3-0.5 mm long; anthers blue; posterior anthers with both anther sacs, the anterior, more distal anthers with only I anther sac; anther sacs about 0.6 mm long, hirtellous along the suture margins and glandular on the connectives; stigmas located between the anterior and posterior anthers, lower stigma lobe 0.3 mm long, upper lobe 0.1  -oak community, 6 Aug. 1974, D. H. Riskind, B. Burleson  and J. T. Baker 1745 (LL); open disturbed areas around Campo 2, in the high country, forest border area in the general area of mesic coniferous forest with Abies coahuilensis, Pseudotsuga, Pinus strobiformis, rhyolytic, near 28"59'30"N lat, 102"36'30"W long, rhizomatous perennial, flowers purple-violet with white in center of lower lip, 2300 m, 7 Aug.Scutellaria carmenensis initially appears most similar to S. parvula Michx. in leaf shape, vestiture and presence of rhizomes, but differs in having larger flowers and black, uniformly tessellate, tuberculate mericarps not yellowish mericarps that are distinctively marked with an encircling band and peglike processes as in S. parvula (Lane 1983).Similarities also exist with S. tuberosa Benth. of western United States from southern Oregon through California to northern Baja California, Mexico but the latter has more strongly toothed leaves with longer petioles, more coarse, long villous vestiture on leaves and stems and the tendency to form tubers on the rhizomes, features not noted in S. carmenensis.Because of the presence of rhizomes, it would appear that the new taxon would lie within Epling's (1942) sect.Galericularia, however, as noted by Richard Olmstead who recently completed a study ofthis section and who has seen specimens of the new species, S. carmenensis has slender, fibrous rhizomes, not fleshy rhizomes that are swollen at the internodes as is characteristic of sect.Galericularia.Also the mericarps of the new species are black and uniformly tessellate, a pattern characteristic of other species of sect.Resinosae and shows no indication of a continuous band as is found in most species of sect.Galericularia (Lane 1983).Olmstead feels that distributionally and in mericarp sculpturing, the new taxon would appear to better fit into sect.Resinosae with closest relationships to the species complex including S. resinosa Torrey, S. wrightii Gray, S. potosina Brandegee and S. tessellata Epling ex Kearney & Peebles, species of the Chihuahuan Desert Region.From these species the new species differs in the presence of rhizomes, and the tendency for the inner surface of the corolla tube to be glabrous above the calyx, not with a villous interior annulus above the calyx.