Justicia maguirei Wassh.

Authority

Wasshausen, Dieter C. 1990. Justicia maguirei, a new species of Acanthaceae from Guyana. Mem. New York Bot. Gard. 64: 235-238.

Family

Acanthaceae

Scientific Name

Justicia maguirei Wassh.

Description

Latin Diagnosis - Herba, caulibus obscure quadrangularibus, glabris vel parce puberulis; folia superiora conspicue ampla, lamina elliptica vel ovata, breviacuminata vel acuminata, basi rotundata, coriacea, utrinque glabra vel subtus secus costam minute pilosa; petioli breves; thyrsus terminalis, densifloms, contractus, pedunculis et rhachidibus puberulis; bracteae et bracteolae anguste triangulares, parce hirtellae et ciliatae; calycis segmenta lanceolata, cillata; corolla infra glabra, sursum pilosa, labio superiore erecto, oblongoelliptico, apice obtuso et emarginato, labio inferiore trilobato, lobis ovatis, rotundatis; stamina exserta; lobi antherarum leviter superpositi.

Species Description - Herbs rarely exceeding 1 m high, erect or ascending, simple or moderately branched; stems obscurely quadrangular, shallowly sulcate, at least above, glabrous or sparingly pubemlous, the trichomes curved and subappressed, about 0.5 mm long, disposed more or less in 2 rows, the intemodes ofthe stem 3-5.5 cm long; leaf blades elliptic to ovate, 9-13.5 cm long and 3.5-6.5 cm wide, with the uppermost pair of leaves conspicuously larger (12-13.5 cm long, 5.5-6.5 cm wide), short-acuminate to acuminate, obtuse or rounded at base, firm and somewhat coriaceous, entire or undulate, both surfaces glabrous or the costa beneath minutely and inconspicuously pilose, the costa and lateral veins (6-8 pairs) prominent, the cystoliths of both surfaces small and rather prominent under a lens, 0.2 mm long; petioles short, 3-4 mm long, thick and puberulous flowers in a short, dense, terminal thyrse 4-5 cm long and 1.5-2 cm broad, the flowers and bracts more or less secund, the rachises and peduncles rather densely and bifariously puberulous, the trichomes erect or ascending, about 0.2 mm long, the peduncles 1.5-4.5 m long, the nodes ofthe thyrse bearing a pair of small leaves (their blades 1.0-1.8 cm long and 0.3-0.7 cm wide); bracts subtending the flowers narrowly triangular, 2.5-3 mm long, 1 mm wide at base, carinate, mucronulate at apex, firm, sparingly hirtellous and ciliate, the trichomes rigid, mostly erect, 0.1 mm long or the marginal trichomes somewhat longer; bracteoles narrowly triangular, 2-3 mm long, 1 mm wide at base, carinate, mucronulate at apex, firm, glabrous or sparingly hirtellous and ciliate, the trichomes similar to those of the bracts, the cystoliths conspicuous under a lens; calyx 6-7 mm long, deeply segmented, the five segments lanceolate, 5.5 mm long, 1.75 mm wide slightly above the middle, acuminate, the tip curved, the costa prominent, bearing dorsally a few ascending trichomes 1 mm long, the margins ciliate, the trichomes white, spreading or ascending, 0.5 mm long; corolla color not indicated but probably purple or red, 1.8-2 cm long, glabrous toward base, finely pilose toward tip, the trichomes spreading, to 0.4 mm long, the nerves conspicuous, the tube 7 mm long, 3 mm broad at base, gradually enlarged to 7 mm at mouth, the upper lip oblong-eUiptic, more or less erect, about 10 mm long, 7 mm wide at middle, plicate, dorsally pilose, minutely glandular-puberulous on the upper surface, rounded and emarginate at tip, the lower lip ovate, spreading, 14 mm long, 11 mm wide, transversely fluted, saccate, 3-lobed, the lobes ovate, rounded, 3 mm long, the middle lobe 5 mm wide, the lateral lobes 3 mm wide; stamens exserted 8 mm beyond the mouth ofthe corolla, the filaments flattened and glabrous, the anther lobes slightly superposed, the connective 0.8 mm broad, the upper lobe 0.75 mm long, 0.5 mm broad, white-pubemlous on margin, muticous and subapiculate at base, the lower cell 0.5 mm long and 0.25 mm broad, white-puberulous on margin, tipped by a white apiculus about 0.5 mm long; pollen grains 2-porate, bilateral, 37 x 28 µm, the equatorial outline of the pollen with a distinct swelling at the equator, the trema area micro-reticulate transversed by two rows of 4-5 insulae (Fig. 2a, b); style about 15 mm long, glabrous, the stigma minutely bilobed; ovary glabrous; capsule wanting.

Discussion

Distribution and Ecology: Known only from the type locality. Justicia maguirei superficially resembles J. guianensis (N. E. Browne) Wasshausen. However, in J. guianensis the bracts and bracteoles are linear-lanceolate, 5-7.5 mm long, the calyx segments are linear-lanceolate, 6.2-7.4 mm long, 1.4 mm wide and the leaf blades are lanceolate or ovate-lanceolate, acute, 1.5-3.8 cm wide, with the upper pair of blades similar in size to those on the remainder of the stem. In contrast, J. maguirei has bracts and bracteoles narrowly triangular, 2-3 mm long, the calyx segments are lanceolate, 5.5 mm long, 1.75 mm wide and the leaf blades are elliptic to ovate, 3.5-6.5 cm wide, short-acuminate to acuminate, with the upper pair of blades conspicuously larger in size (12- 13.5 cm long, 5.5-6.5 cm wide).

Distribution

Type. Guyana. Southem Pakaraima Mountains, base of Chimapu Falls, 700 m alt., 7 Sep 1961, Bassett Maguire, Celia K. Maguire & G. Wilson-Browne 46132-A (holotype N Y ; isotype US).

Guyana South America|