241. SALVIA DARCYI Labiatae

James Compton

The known number of Mexican species in the spectacular genus Salvia L. is now thought to surpass 275. Most of these fall into the New World subgenus Calosphace (Benth.) Epling, an assemblage of species distinguished by the long anther connectives which are usually longer than the filaments and which fuse to form a rudder-like appendage. On a recent expedition to Mexico in 1991 an attractive and undescribed species of undoubted horticultural value was discovered.

Salvia darcyi J. Compton is named after John d’Arcy, plantsman and collector with the Compton, d’Arcy and Rix team. I t is known only from the type locality in the Sierra Madre Oriental range of northeastern Mexico and was found growing among limestone rocks, a large colony of it filling a ravine at 2800 m. The ravine was 14 km west of Galeana, approximately 50 km south-east of Saltillo in Coahuila State and 60 km south of Monterey in Nuevo Leon State.

Epling (1939) in his revision of Salvia subgenus Calosphace distinguished section Cardinales Epling from section Fulgentes (Benth.) Epling by the length of the upper corolla lip. Both sections possess a prominent pair of papillae within the corolla tube but, whereas in section Cardinales the corolla lip is subequal to or longer than the lower, in section Fulgentes it is shorter. Ramamoorthy ( 1984) identified Salvia cardinalis Kunth as being conspecific with Salvia fulgens Cav., thereby automatically merging the two sections and making Salvia section Fulgentes the correct name for the combined sections. He published a new section, Holwaya Ramamoorthy, to accommodate the remaining seven species of the former section Cardinales. Salvia darcyi belongs in section Holwaya and should be placed next to Salvia stolonifera Benth. I t can be incorporated into Epling’s key as follows:

Herbs to 1.5 m or more; stems and leaves densely glandular- pubescent; inflorescence whorls with 4-6 flowers ........... S. darcyi

Herbs to 60 cm; stems and leaves sparsely glandular-pubescent; inflorescence whorls with 1-4 flowers . . . ... . .... . ..... ..... . S. stolonifera

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Salvia darcyi

Plate 241

MARK FOTHERGILL

Salvia darcyi is closely related to S. stolonifera Benth., although as far as the distribution is concerned they are separated by some 960 km, S. stolonifera occurring in the southern Mexican States of Oaxaca and Guerrero. Both species spread by means of stolons and there are similarities in calyx and corolla morphology. Salvia darcyi differs in its much larger stature, greater density of glandular-pubescence, more densely-flowered inflorescences with more flowers per whorl, and longer bracts.

CULTIVATION. Salvia darcyi is a fast-growing species best treated as a half hardy perennial which is easily raised from shoot tip cuttings each year. In Britain, flowering occurs from June onwards for several months and flowering-sized plants can be produced within three or four months. The whole plant is pleasantly aromatic; even the bright scarlet corollas are glandular-viscid. The stems are unfortunately rather brittle, so the choice of outdoor situation must be considered carefully. Large plants soon form by means of stolons and the plants seem indifferent to soil pH or texture. Pot grown specimens may be kept very dry during winter when the plants become almost entirely herbaceous, dying back to the perennating rootstock. Salvia darcyi may be propagated by seed sown under glass in spring or from cuttings ofthe new growth taken in March or April.

Salvia darcyi J. Compton sp. nov. Species mexicana Salvia stoloniferae affinis sed praecipue caulibus et foliis majoribus pilis glandulosis viscidisque dense vestitis differt. Folia caulina maturitate acuminata. Bracteae caudatae caducae. Stylus infra apicem parum (haud dense) villosus. TYDUS: Mexico, Sierra Madre Oriental, 20 October 1991, J. Compton, J d’Arcy and E. M . Rix CDR 1245 (holotypus K; isotypus E, MEXU). DESCRIPTION. Perennial herb to 1.5 m tall, producing stolons. Stem

branching above, densely covered in simple glandular pubescence; inter- nodes 4-6 cm long near base of stems, increasing to 10 cm on upper parts of stems. Leaves deltoid-cordate, lamina and petiole both densely glandular- pubescent; lamina 4-8 cm X 4-9 cm, basal lobes forming a wide cuneate base tapering to the petiole; margin crenate to crenate-serrate; upper surface dark green, reticulate-veined; lower surface pale green; apex obtuse on young leaves becoming acute to acuminate on older leaves at time of anthesis; petiole 2-7 cm. Infrorescence consisting of interrupted racemes 10- 22 cm long, upright. Flowers borne in whorls of 4 or, more commonly, 6 in two pairs of 3 with the central flower in each pair opening earliest. Bracts borne in pairs subtending the whorls, caducous, glandular, ciliate, caudate, 8-14 mm long. Pedicels 4-12 mm long. Calyx 2-lipped, densely glandular- pubescent outside; upper lip slightly longer than the lower, 12 mm long, 7-

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Salvia darcyi. A, half flower, X 2; B, stigma, side view, X 6; C, bract, X 2; D, calyx, X 2; E, lower (early) leaf, X 2/3; F, upper (late) leaf, X V 3 . Drawn by Mark Fothergill.

veined, acute to acuminate; lower lip 2-lobed, lobes acute. Corolla bright scarlet, 2-lipped; tube 25-27 mm long with a prominent pair of papillae within; basal part of tube invaginate, narrowing abruptly; upper lip longer than lower, 12-17 mm long, straight, margins deflexed; lower lip with 3 lobes, middle lobe the widest, bifid at the apex, 5-8 mm long. Style slightly exserted, 2-lobed at apex, finely glandular-pubescent below the bifurcation on the posticous surface; upper style arm longer than lower, apex reflexed, lower style arm thicker and straight. Stamens 2, distal connective arms arcuate within the upper corolla lip. Nutlets ovoid, 3 mm long, smooth, dark brown.

DISTRIBUTION. North-eastern Mexico, in the Sierra Madre Oriental range. HABITAT. In ravine among limestone rocks at an altitude of 2800 m.

ACKNOWLEDGMENTS. The author wishes to thank Dr Ray Harley and Dr Alan Paton for their assistance in the preparation of this paper and Professor W. T. Stearn for checking the Latin diagnosis for me.

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REFERENCES

Epling, C. (1939). Revision of Salvia L. subgenus Calosphace (Benth.)

Ramamoorthy, T. P. (1984). Typifications in Salvia. Taxon 33, 2: 322-323. Epling. Repert. Spec. Nov. Regni Veg. Beih. 110: 295-299.

242. AERANGIS ARACHNOPUS Orchidaceae

Isobyl la Croix

The genus Aerangis was established by H. G. Reichenbach in 1865 for plants resembling Angraecum, but with a long, slender rostellum and pollinia with long stipites. The type species was given as Aerangis

Jlabelliflia from Angola but this name is now considered to be a synonym of A . brachycarpa, which was described from Ethiopia in 1850 by A. Richard as Dendrobium ? brachycarpa. This was not the first species of Aerangis known; that was the West African Aerangis biloba (Lindl.) Schltr., described by Lindley as Angraecum bilobum in 1840 from a specimen collected in what is now Ghana. The next was the East African and Southern African A . mystacidii (Rchb. f.) Schltr., described from a South African specimen in 1847, again as an Angraecum. The third species known was that designated as the type species of the genus and the fourth was Angraecum arachnopus in 1854, now known as Aerangis arachnopus (Rchb. f.) Schltr. I t is rather surprising that this species has been known for so long, as it is virtually unknown in cultivation and is apparently none too common in the wild. The type specimen was said to have come from Ghana, but there is some doubt as to this as the species has not been found there since.

The above information is based on the work of Stewart (1979), to whom all lovers of the genus must be eternally grateful since, although the genus is almost always easily recognizable, deter- mining the species is often more difficult, and many have been described under a range of names. A . arachnopus is no exception. Rolfe (1897) described this species as Angraecum batesii from a specimen collected in Cameroun. He also listed Angraecum arachnopus Rchb. f. in his account of the genus, but said that he knew the species only from the original description.

In November 1990 I visited the Republic ofCongo to take part in a survey, sponsored by the oil company Conoco and organized by the

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