Justicia alanae T.F. Daniel, 2019

Daniel, Thomas F., 2019, New and Reconsidered Mexican Acanthaceae XIII. Justicia, Proceedings of the California Academy of Sciences 66 (3), pp. 61-85 : 62-67

Justicia alanae T.F. Daniel , sp. nov.

TYPE.— MEXICO. Puebla: Mpio. Xicotepec de Juárez, 5 km NE de Xicotepec, carr. a La Ceiba , 20°19′N, 097°48′W, 1200 m, bosque mesófilo perturbado, 24-II-1987 (flr, frt) , G. Toriz A., A. Campos V., O. Vega T., & P. Tenorio L. 298 (holotype: MEXU-image only; isotype: CAS!). Figures 1–3 .

Perennial herbs to 1.5 m tall. Young stems subquadrate-sulcate, becoming subquadrate to quadrate proximally, distally densely 2-fariously pubescent with retrorse to retrorsely appressed eglandular trichomes 0.2–0.4 mm long and often also with sparse and flexuose eglandular trichomes to 0.4 mm long between the 2 lines of denser trichomes, trichomes usually with conspicuous maroon septae, stems soon becoming more sparsely pubescent or glabrate. Leaves petiolate, petioles 20–95 mm long, at least medial ones nearly as long as or longer than blade, blades ovate, 45–140 mm long, 16–65 mm wide, 2.0–2.8 times longer than wide, acuminate to falcate at apex, subcordate to rounded to truncate at base, adaxial surface glabrous, abaxial surface pubescent along main veins with antrorse to antrorsely appressed eglandular trichomes 0.1–0.2 mm long, margin entire to subsinuate, sparsely ciliate. Inflorescence of axillary and/or terminal pedunculate dichasiate spikes or more commonly panicles of dichasiate spikes to 90 mm long (including peduncles but excluding flowers), 6–10 mm wide near midspike (measured flat), (alternate or) opposite at nodes, sometimes clustered in leaf axils, peduncles of spikes to 40 mm long, pubescent like young stems or becoming ± evenly pubescent distally with variously oriented eglandular trichomes 0.05–0.2 mm long, rachis pubescent like peduncle; dichasia opposite or alternate at spike nodes, 1 per axil, 1-flowered, sessile. Bracts at a node homomorphic (when each subtending a dichasium, i.e., dichasia opposite and both bracts fertile) or heteromorphic when only 1 dichasium present at a node (i.e., dichasia alternate and 1 bract sterile); fertile bracts oblanceolate to elliptic to obovate to broadly spatulate, 3.2–8 mm long, 1–4.5 mm wide, rounded to acute at apex, abaxially and marginally pubescent with flexuose eglandular trichomes to 1 mm long and also with mostly erect glandular trichomes 0.05–0.2 mm long, glandular trichomes often sparse and rarely absent on some bracts; sterile bracts conspicuously reduced, narrowly linear to oblanceolate, 0.7– 4 mm long, 0.2–0.8 mm wide. Bracteoles (linear to) oblanceolate to narrowly obovate-spatulate, 2.5–7.5 mm long. 0.5–1.6 mm wide, pubescent like bracts. Flowers sessile. Calyx 5-lobed, 3–4 (– 4.5 in fruit) mm long, lobes homomorphic, lance-linear to lance-subulate, 2.6–3.5 (– 4 in fruit) mm long, 0.3-0.5 mm wide, abaxially nearly glabrous to sparsely pubescent with flexuose to antrorse eglandular trichomes and sometimes also with very sparse and inconspicuous glandular trichomes <0.05 mm long. Corolla white with maroon markings on lower lip, 7.5–13 mm long, externally pubescent with erect to flexuose eglandular trichomes 0.05–0.3 mm long, tube 5–8 mm long, narrow proximal portion of tube 2.5–4 mm long, longer than or equal to throat in length, throat 2–4 mm long, 1.8–3 mm in diameter at mouth (measured flat), upper lip 3–5 mm long, 2-fid, lower lip 3–5.5 mm long with three lobes 1–2 mm long and 1.5–2.5 mm wide, central lobe largest. Stamens 5–5.5 mm long, filaments glabrous, thecae of a pair superposed (contiguous, overlapping by 0.1–0.2 mm, or separated by a gap to 0.05 mm long), ± parallel or somewhat offset, subequal in size, upper theca 0.8–1.1 mm long, lacking a basal appendage, lower theca 1–1.4 mm long, with a prominent basal appendage 0.5–0.6 mm long, appendage oriented 90° to fertile portion of theca, thecae dorsally pubescent with flexuose eglandular trichomes to 0.7 mm long (lower theca often with shorter and less prominent trichomes); 2 densely pubescent staminode-like invaginations of the corolla present near midpoint of corolla tube. Pollen 3-colporate, 6-pseudocolpate, exine between colpi and pseudocolpi sometimes partially separating into insulae. Style 6–11 mm long, proximally pubescent with eglandular trichomes, stigma subcapitate, 0.05–0.1 mm long. Capsule 5–7 mm long, pubescent with erect to flexuose eglandular trichomes 0.1–0.3 mm long, stipe 1–2.5 mm long, head 4–4.5 mm long. Seeds flattened, ± ovate to broadly oblong, 1.6–2.2 mm long, 1.3–1.7 mm wide, surface minutely papillose, margin entire.

PHENOLOGY.— Flowering: February–April; fruiting: February–April.

DISTRIBUTION AND HABITATS.— Mexico (Puebla; Fig. 2 ), endemic to the Sierra Nororiental in northern Puebla; plants occur in tropical subperennial forest and mesophytic montane forest (these sometimes secondary forests or plants occurring at disturbed sites therein) at elevations of 276– 1200 meters.

CONSERVATION.— Based on the four known collection sites for this species, the EOO = 804 km 2, the AOO = 16 km 2, and the greatest linear extent of its distributional range (NW–SE) = 51 km. No collections are known to occur in protected areas. In addition to the type, at least three other collections have been made at different times at the type locality. No threats have been identified for this species, and thus it is provisionally assessed as Least Concern (LC).

ETYMOLOGY.— The epithet honors Jonathan Amith, a proponent of this species who also took useful photographs of it in Puebla, and his sometime young field assistant and daughter Alana.

PARATYPES.— MEXICO. Puebla: Mpio. Xicotepec de Juárez, 5 km NE de Xicotepec, carr. a La Ceiba , 20°19′N, 097°48′W, A. Campos V. & G. Toriz A. 206 ( CAS, MEXU-image only), P. Tenorio L., G. Toriz A., A. Campos V. & O. Vega T. 12613 ( CAS, MEXU-image only), G. Toriz A. & A. Campos V. 374 ( CAS, MEXU-image only); Mpio. Ayotoxco de Guerrero, Cuauhtémoc, en la loma de Santa Cecilia, cerca del Río Atekakalach , 20.03894°, -97.40643°, M. Jiménez C. & M. Gorostiza S. 31242 ( CAS); Mpio. Atlequizayán, Atlequizayán, camino a Lhimakgatlhakgna’, en localidad de Tatitsapsni’, 20.00266°, -97.62263°, C. Ledesma C., O. López F. & M. Gorostiza S. 22328 ( CAS); Mpio. Ahuacatlan , Agua Dulce, 4 km SE de Ahuacatlan, brecha a Zapotitlan, 20°01′N, 097°50′W, P. Tenorio L., G. Toriz A., A. Campos V. & O. Vega T. 12722 ( CAS; MEXUimage only), G. Toriz A., A. Campos V., P. Tenorio L. & O. Vega T. 320 ( CAS, MEXU-image only) .

DISCUSSION.— In spite of slight variation in type and disposition of cauline pubescence and variation in degree of glandularity among individuals, plants of J. alanae are morphologically homogeneous. Distinctive features of this species include the variation in bracts with either two fertile and homomorphic bracts at a node or one sterile and one fertile bract at a node with those bracts differing in size and usually also in shape. Heteromorphic bracts appear to be more frequent on spikes from leaf axils and/or on those forming the lateral branches of a panicle. Homomorphically bracteate spikes tend to be the ones terminating shoots. Bracts and bracteoles of J. alanae are green and are often tinged with maroon at the margins and apex ( Fig. 1 ). Relatively long and naked petioles are prominent in this species, as are the pouch-like invaginations of the corolla near the midpoint of the corolla tube (cf. Daniel 2002). These staminode-like structures appear to be associated with the basal portion of the rugula and veins in the corolla tube leading thereto.

Justicia alanae undoubtedly pertains to a group of species known from various regions of the Neotropics that were discussed by Wasshausen and Daniel (1995) and Daniel (2002, 2007). A suite of morphological characters shared among four of these species ( J. chol T.F. Daniel , J. karsticola T.F. Daniel , J. alanae , and J. wendtii T.F. Daniel ) include: maroon septa of the cauline trichomes; some or all of the bracts hetermorphic (by size, shape, and whether fertile or sterile) and with their abaxial surface nearly always including glandular trichomes; relatively small corollas with maroon markings and with a pair of invaginations forming pouch-like and pubescent appendages internally in the corolla tube; anther thecae of a pair parallel to subparallel, unequally inserted to superposed, both dorsally pubescent with the lower one usually less densely so, and with the lower theca bearing a conspicuous basal appendage (commonly oriented at a 90° angle to the fertile portion of the theca); and 3-colporate, 6-pseudocolpate pollen ( Fig. 3 ). These four similar species can be distinguished by the key below. Other similar Mexican species with either heteromorphic bracts and/or staminode-like invaginations of the corolla, but which differ conspicuously by their pollen, include J. nevlingii Wassh. & T.F. Daniel (pollen 4-colporate, 8-pseudocolpate) and J. chimalapensis T.F. Daniel (pollen 2-colporate with apertures flanked on each side by 1 row of insulae).

1a. Bracts inconspicuously ciliate with trichomes (0.05–0.2 mm long) and sometimes also with scattered flexuose eglandular trichomes to 0.3 mm long; corolla externally pubescent with eglandular and glandular trichomes; seeds sparsely pubescent with branched eglandular trichomes; southern Veracruz. J. wendtii 1b. Bracts conspicuously ciliate with trichomes up to 2 mm long (some, usually most, longer than 0.3 mm);

corolla externally pubescent with eglandular trichomes only; seeds lacking branched trichomes..... 2

2a. Cauline trichomes mostly retrorse to retrorsely appressed; petioles elongate, at least medial ones nearly as long as or longer than blade, blades rounded to truncate to subcordate at base; floral bracts opposite or alternate; corolla white and with maroon markings; stamens 5–5.5 mm long; Puebla ........ J. alanae

2b. Cauline trichomes flexuose to antrorse; petioles not elongate as described above, blades acute to attenuate at base; floral bracts opposite; corolla pale yellow to yellow-green and with maroon markings; stamens 3.5–4.5 mm long............................................................... 3

3a. Fertile bracts rounded- to truncate-apiculate at apex; inflorescence of axillary pedunculate dichasiate spikes to 6.5 cm long (including peduncles but excluding flowers), dichasia alternate, 1-flowered; Chiapas and Tabasco ................................................................ J. chol

3b. Fertile bracts rounded-subacute to acute at apex (lacking a conspicuous apiculum); inflorescence of (axillary and) terminal pedunculate panicles (7–15 cm long) of spicate axes, spicate axes (= modified dichasia?) opposite, mostly 3–5-flowered; southern Veracruz ............................ J. karsticola

Figures

FIGURE 1. Justicia alanae (Jiménez C. & Gorostiza S. 31242). –A. Habit. B. Inflorescence. C. Flowers, front view. D. Flower, profile view. E. Capsule. F. Seed. Field photos B–D by J. Amith, used with permission.

FIGURE 2. Map of part of southern Mexico showing distributions of Justicia alanae and J. totonaca.

FIGURE 3. Scanning electron micrographs of Justicia pollen I. A–C. Justicia amplifolia. A. Apertural view (Amith & Mendoza 1419). B. Apertural view (Luther s.n.). C. Interapertural view (Luther s.n.). D–F. Justicia alanae (Toriz A. et al. 320). D. Apertural view. E. Interapertural view. F. Polar view. Scales = 10 µm.