Amaranthus saradhiana S. Arya, V.S.A. Kumar, W.K. Vishnu & Rajesh Kumar, 2019

Arya, Sindu, Kumar, Venugopalan Nair Saradamma Anil, Vishnu, Walsan Kalarikkal & Kumar, Thaliyangal Rajesh, 2019, Amaranthus saradhiana (Amaranthaceae) - a new species from southern Western Ghats of Kerala, India, Phytotaxa 403 (3), pp. 230-238 : 236

Amaranthus saradhiana S. Arya, V.S.A. Kumar, W.K. Vishnu & Rajesh Kumar sp.nov. ( Fig 1. a–k , 3. a–h )

Diagnosis: The new species is morphologically similar to Amaranthus spinosus but differs by means of its sparsely pubescent stem having slightly undulating outline, purple color of stem and petiole, total absence of spines in the terminal spike, emergence of one spine from each node and prominent green stripes in tepals having acute apex in female flowers.

Type:— INDIA. Kerala: Thiruvananthapuram district, Palode , way to Kulathupuzha , 110 m, 8.970 N, 77.30E, 4th February 2017, V. S. Anil Kumar & S. Arya 86207 (Holotype: TBGT; Isotype: MH, CMPR)

Annual herb, about 80–100 cm high, profusely branched, branches with or without grooves, spinescent; spines arise from the leaf nodes, distributed throughout stem and branches; 0.4–0.5 cm long. Stem angular, erect ascendant, purple in color, glabrous or with sparse hairs. Leaves simple, alternate, petiolate; petiole terete, glabrous, 2–5 cm long; lamina 1.5–7.4 × 1.5–4.5 cm, ovate to lanceolate, base attenuate, margin entire, apex obtuse or emarginated; dark green, base tapering to slender, sparsely pubescent on the main veins below. Inflorescence cymose with long slender terminal or axillary spikes, axillary spikes are in sessile clusters, purple in color. Peduncle terete, purple coloured, sparsely pubescent. Bracts and bracteoles minute, 0.05–0.1mm, apex ovate tolanceolate margin delate or rhombic, glabrous and white. Flowers unisexual, yellowish green in colour. Staminate flowers: confined to the terminal end of the spike, 3. mm across; tepals 5, 0.5–1.5 mm, calycine, unequal; stamens 5; anthers sagittate. Pistillate flowers: 4 mm across; tepals 5 1.5–2 mm with prominent green stripes, acute at apex; ovary 1-celled, pubescent; ovules solitary; stigma 2–3. Fruit shorter than perianth lobe. Seeds minute, more or less globose, 937.8 × 983.8μm, a beak like extension near the hilum, spermoderm sculpturing faint, pollen grains spheroidal, polypantoporate, 22.46μm across, spinulose exine sculpturing, visible frequency of pores range from 26–30, number of ektexinous bodies range from 3–5 with varying degrees of fusion.Fruit is an orbicular utricle, compressed. Fruiting throughout the year.

Flowering and fruiting:—June–December.

Etymology:—The species is named in recognition of Mrs. Saradhamma Venugopal, mother of the second author who used to give constant encouragement for doing botanical research.

Distribution and ecology:—The species occurs in dry waste lands and along the Palode–Kulathupuzha–Thenkasi road sides. The species is also found growing along the roadsides in Palayam, Thiruvananthapuram. Several accessions of the taxon has been collected by the authors from various districts of the state.

Additional specimens examined (Paratypes):— INDIA: Kerala: Thiruvananthapuram District, Jagathy to Poojappura, 18m, 30th May 2017, V.S. Anil Kumar & S. Arya 87290 (TBGT), Alappuzha District, Vellakinar, 8m, 12th September 2017, V.S. Anil Kumar & K. Vishnu Walsan 87295 (CMPR). Ernakulan District, Ernakulam– Kaloor route, 4 m, 9.9312° N, 76.2673° E, 22nd October 2017, V.S. Anil Kumar & T. Rajesh Kumar 87312 (CMPR). Kollam District, Shengottai–Kollam National Highway, 3 m, 8.9751° N, 77.2491° E, 10th October 2018, S. Arya & K. Vishnu Walsan 87338 (TBGT). Kannur District, Kannur–Thavakkara region, 1.02m, 1° 52’ 0” N, 75° 21’ 55” E, 18th October 2018, V.S. Anil Kumar & K. Vishnu Walsan 87348 (TBGT). Kollam District, Kollam– Karunagappally region, 3 m, 9.0654° N, 76.5315° E, 22nd October 2018, S. Arya & T. Rajesh Kumar 87360 (CMPR). Alappuzha District, Cherthala–Alappuzha region, 11m, 9.4981° N, 76.3388° E, 11h November 2018, V.S. Anil Kumar & K. Vishnu Walsan 87365 (TBGT).

Figures

FIGURE 1. Amaranthus saradhiana a. Habit.b. Spine at the node. c. Protrusion at the leaf tip. d. Spike. e. Striped tepals. f. Cluster of male flowers. g. Male flower. h. Cluster of female flowers. i. Female flower with bifid stigma. J. Female flower with trifid stigma. K. Seed.

FIGURE 3. Amaranthus saradhiana a. Habit. b. Spine at the node. c. Protrusion at the leaf tip. d. Spike. e. Male flower. f. Female flower with trifid stigma. g. Female flower with bifid stigma. h. Seed.