Commelina texcocana Matuda

Commelina texcocana Matuda View in CoL

Figs 2 View Fig , 20 View Fig ; Table 1 View Table 1

Commelina texcocana Matuda ( Matuda 1955: 60) View in CoL .

Etymology

The epithet derives from the combination of the type locality ʻTexcocoʼ + the Latin suffix ʻ -ānā ʼ (indicating a place of origin).

Type material

MEXICO – México • Texcoco , Molino de la Flor ; 2300 m a.s.l.; 6 Aug. 1950; fl., fr.; E. Matuda 19249; lectotype: MEXU [ MEXU00090886 About MEXU ]!, designated by Espejo-Serna & López-Ferrari (1995); isolectotypes: F [ V0045324 F, V0045323F ]!, MEXU [ MEXU00090880 About MEXU ] !.

Selected material examined

MEXICO – Distrito Federal • Pedregal ; 16 Jun. 1938; fl.; E.K. Balls 4822; US. – Guanajuato • Apaseo el Grande , cerca de Ixtla ; 16 Aug. 1986; fl.; J. Rzedowski 40348; MEXU. – Hidalgo • La Veguita , 5 km al NE de Metzquititlán; 3 Nov. 1975; fl., fr.; F. González Medrano et al. 8445; MEXU. – Jalisco • Valle de México, Mt. Zacoalco, près Gualalupe ; 10 Aug. 1907; fl.; G. Arsène 648; CLF, P 4ex. – México • Cambaya , San Juanico [San Juan Ixhuatepec], Tlalnepantla de Baz ; 11 Aug. 1913; fl.; G. Arsène 8787; P. – Michoacán • Morelia Punguato ; 5 Sep. 1917; fl., fr.; G. Arsène 8661; B, CAS, K, MA, MEXU, MO, P 2 ex, US. – Puebla • vicinity of Puebla ; 11 Aug. 1906; fl.; G. Arsène 492; US. – Querétaro • parte baja del cerro en Tequiquiapan ; 11 Oct. 2004; fl.; L. Hernádez 5478; MEXU, QMEX .

Description

Herbs 70–150 cm tall, scrambling, perennial, robust, terrestrial or paludal. Roots tuberous, cylindric, with apical fusiform tubers. Rhizome short. Stems dimorphic, branched in the upper third; internodes 0.4–9.8 cm long, distally shorter, green suffused with red to atro-vinaceous, glabrous, with a sparse line of acicular hairs opposite to the leaves, hairs hyaline, primary branches ascending, rooting only at the base, secondary branches longer than the primary branches, scrambling, apex ascending. Leaves distichously-alternate, evenly distributed along the upper part of the stem, pseudopetiolate; sheaths 1.4–3.6 cm long, light green suffused with red to atro-vinaceous, glabrous, with a sparse line of setose hairs opposite to the blade, hairs acicular, hyaline, margin upright, ciliate, hairs acicular, hyaline; pseudopetiole inconspicuous to up to 5.6 mm long; blades 2–10.5 × (0.4–0.5–) 1.2–3.1 cm, elliptic to lanceolate, straight, membranous to thinly chartaceous, adaxially dark green, abaxially light green, glabrous on both sides, base slightly asymmetric to symmetric, cuneate, margin flat, scabrid, apex acute to acuminate; midvein conspicuous, adaxially impressed, abaxially prominently obtuse, secondary veins 2–3 pairs, adaxially conspicuous, abaxially inconspicuous, becoming conspicuous on both sides when dry. Synflorescence composed of a solitary main florescence, restricted to the apex of the stems and forming a dense second-degree synflorescence. Inflorescences leaf-opposed, peduncle 1.2–4.1 cm long, the same length or longer than ½ length of the spathe, straight, velutine, hairs acicular, with a line of minute hook-hairs opposed to the spathe, hairs hyaline to white; spathe 1.9–4.6 × 1.3–3.9 cm, cordate, oblique to the peduncle and pointing downwards or continuous to the peduncle and pointing upwards, concolourous with the leaves, internally inconspicuously mucilaginous, base free, subcordate to round, externally glabrous to velutine, hairs hyaline to white, margin flat, apex acuminate, slightly falcate, veins 3–4 pairs, inconspicuous, becoming conspicuous when dry; upper cincinnus vestigial, flowerless, peduncle inconspicuous to up to 3.8 mm long, included, gently recurved at pre-anthesis and anthesis, recurved and exserted at post-anthesis and fruit, glabrous with some odd hook-hairs towards the apex, hairs hyaline; lower cincinnus 2–5-flowered, flowers mainly bisexual, rarely staminate, peduncle 6.2–11.2 mm long, thickened in fruit, sparsely puberulous with minute hook-hairs towards the apex. Flowers chasmogamous, zygomorphic, enantiostylous (style dislocated to the opposite side to the medial stamen); floral buds 2.6–5.7 × 3.7– 6.1 mm, obovoid, light green or white to light blue, dorsally setose, hairs hyaline; pedicel 1.9–5.5 mm long, deflexed in bud and at anthesis, reflexed and elongating in fruit, light green, pilose with acicular hairs, hairs hyaline; sepals light green, opaque, persistent and accrescent in fruit, dorsal sepal 3.8–5 × 1.3–2.9 mm, elliptic to narrowly triangular, concave, setose along the midvein, hairs acicular, long, hyaline, apex acute, lower sepals 4.4–5.9 × 2.8–4.6 mm, sessile, free, triangular to widely trullate, concave, glabrous, apex obtuse; paired petals 8.3–11.5 × 5.8–7.4 mm, clawed, claw 2.7–4.3 mm long, white to light blue or mauve-purple to purple, limb 5.6–7.3 × 5.8–7.4 mm, widely reniform to widely rhombic-reniform, white or light blue to blueish-purple, base asymmetric, truncate, apex obtuse, medial petal 4.3–6.1 × 3.5–4.5 mm, shortly-clawed, claw 0.7–1.2 mm long, white to light blue or mauve-purple to purple, limb 3.8–4.9 × 3.5–4.5 mm, widely sagittate, entire, concave, concolourous with the paired petals, opaque, glabrous on both sides, apex obtuse; staminodes 2, medial staminode completely absent, filaments 4–5 mm long, straight to arcuate-decurved, white or light blue, base white or mauve-purple, upper half light blue or purple, antherodes 0.4–0.9 × 0.6–0.8 mm, scarcely X-shaped, white, minute pollen sacs between the upper and lower lobes present, non-polliniferous or producing very few grains, not apiculate between the upper lobes, upper lobes reduced, depressed obovate, much smaller than the lower, lower lobes filiform; lateral filaments 6–8 mm long, gently sigmoid, geniculate distal to the middle, apex gently recurved, white or light blue, base white or mauve-purple, apex light blue or purple, anthers 0.9–1.1 × 0.4–0.6 mm, held near the medial anther, sagittate, pale yellow to yellow, connective white to cream-coloured, pollen yellow, drying ochre; medial filament 5–8 mm long, arcuate-decurved, apex recurved to strongly recurved, white or light blue, base white or mauve-purple, apex light blue or purple, anther 1.5–1.9 × 0.7–0.8 mm, held near the lateral anthers, oblong-sagittate to saddle-shaped, curved, pale yellow to yellow, connective hastate, white to cream-coloured, anther sacs appressed to each other, pollen yellow, drying ochre; ovary 1.3–1.9 × 0.7–1.1 mm, 3-carpellate, 5-ovulate, ellipsoid to widely ellipsoid, green, smooth, glabrous, style 6–8 mm long, equalling or exceeding the stamens, sigmoid, base tapering into the ovary, apex strongly recurved, white or light blue, base white or mauve-purple, apex light blue or purple, deciduous in fruit, stigma capitate, white. Capsules 1–2 per spathe, 6.2–8.1 × 2.8–4 mm, fusiform to ellipsoid, short-stipitate, stipe 0.8–1.4 mm long, fruit wall thick, apex rostrate, not constricted between the seeds when mature, becoming constricted between the seeds when mature, tan-coloured when mature, opaque, smooth, 3-locular, 3-valved, valves splitting to base, dorsal locule 1-seeded, dehiscent, ventral locules 2-seeded, dehiscent. Seeds dimorphic, dark brown to black; dorsal locule seed 3.1–3.9 × 2.3–2.8 mm, free from the fruit wall, ellipsoid, dorsiventrally compressed, ventrally flattened, slightly cleft towards the embryotega, testa shallowly rugose, with some small furrows on the side opposed to the embryotega, densely farinose, farinae cream-coloured, embryotega semilateral, inconspicuous, with a prominent apicule, hilum linear, longer than ½ the length of the seed; ventral locule seeds 1.9–2.5 × 1.8–2.6 mm, free from the fruit wall, triangular, truncate at one end, ventrally flattened, not cleft towards the embryotega, testa shallowly rugose to irregularly rugose, densely farinose, farinae cream-coloured, embryotega semilateral to lateral, inconspicuous, with a prominent apicule, hilum linear, ca ½ the length of the seed.

Distribution

Commelina texcocana is currently endemic to central Mexico (the Distrito Federal and the States of México and Michoacán) ( Fig. 2 View Fig ).

Ecology

It grows in lower altitude water-lodge seasonal formations, generally between bushes and close to water bodies.

Phenology

It was found in bloom and fruits from August to September.

Vernacular names

Tetzocana ( Mexico), hierba del pollo ( Mexico).

Conservation

Commelina texcocana is known from several locations, presents a very wide EOO (251 840 km 2) and a wide AOO (ca 736 km 2), and does not meet the thresholds for criterium B. No information is currently available on this species’ populational trends or threats. Therefore, following the IUCN (2012) criteria and the IUCN Standards and Petitions Committee (2024) recommendations, we recommend C. texcocana should be considered Least Concern (LC, criterium B).

Remarks

Commelina texcocana is similar to C. almandina sp. nov. and C. pallida due to its peduncle and spathe straight, spathe base subcordate to round, pedicels pilose with acicular hairs, style slightly longer than the stamens, stigma white, fruits dehiscent, 3-valved, fruit wall thick, opaque and constricted between the seeds when mature, with apex rostrate, style deciduous in fruit, dorsal locule 1-seeded, ventral locules 2-seeded, and seeds dimorphic, ellipsoid and ventrally flattened ( Table 1 View Table 1 ). As aforementioned, C. texcocana and C. pallida have been traditionally confused due to their morphological similarity. Nonetheless, both of them can be differentiated based on the colouration of their stem, leaf-sheath and leaf-blade indumentum, leaf-blade base shape, shape and posture of the spathe apex, sepals pubescence, shape of the dorsal sepal, the position of the lower sepals, petal colouration, and antherode morphology ( Table 1 View Table 1 ).