Madhuca balakrishnanii E.S.S.Kumar, Shailajakumari & Shareef, 2021

Madhuca balakrishnanii E.S.S.Kumar, Shailajakumari & Shareef View in CoL , sp.nov. ( Figure 1 View FIGURE 1 ).

Type:— INDIA, Kerala, Kollam District, Thodiyur Panchayat, Mararithottam-Muzhangodi , 40 m., 2 February 2021, E.S. Santhosh Kumar, S. Shailajakumari & S.M. Shareef 92429 (holotype TBGT !, isotypes MH!, TBGT!) .

Diagnosis:— Madhuca balakrishnanii is easily distinguished from the two allied species, M. diplostemon and M. insignis by its hairy young shoots, fairly long stipules, sparsely hairy pedicels, inner sepals rufous hairy abaxially, shorter corolla tube, fairly long densely hairy staminal filaments, shorter style and ovoid fruit ( Table 1 View TABLE 1 ).

Description: —Evergreen tree, up to 8 m high; bark fluted, slightly fissured; latex sticky, white; branchlets angular; young branchlets sparsely rufous hairy, later become glabrous; stipules ovate-lanceolate or lanceolate, 3.0–4.0 mm long, rufous hairy without, glabrous within, acute at apex, caducous. Leaves obovate, narrowly or broadly obovate, 7.5–19 × 3.5–7.5 cm, obtuse-cuneate or oblique at base, acute, rounded or emarginate at apex, entire and not thickened at margin, sub-coriaceous, glabrous; midrib prominent, rounded below; secondary veins 13–18 pairs, prominent on both surfaces, tertiary veins finely reticulate, arched near the margin. Petioles 1.0– 1.5 cm long, slightly canaliculated above, rounded below, glabrous. Fascicles axillary, extra axillary or rarely terminal, 1–7-flowered, overtopped with new shoots. Flowers ca. 2.0 × 1.0 cm, pedicellate; pedicels 1.8–2.2 cm long, light green, gradually thickened towards the apex, sparsely hairy. Sepals 4 (2+2), outer lobes broadly ovate, 7.0–9.0 × 6.0–7.0 mm, obtusely acuminate at apex, rufous hairy without, glabrous within; inner lobes broadly ovate, 7.5–8.0 × 5.0–6.0 mm, obtusely acuminate at apex, densely rufous hairy without, glabrous within. Corolla tube campanulate, 1 cm long; lobes 8, oblong, 7.0–8.0 × 1.0–3.0 mm long, rounded at apex, rufous hairy along the midrib without, glabrous within. Stamens 16–18 in 2 whorls; filaments subulate, 2.5–3.0 mm long, densely hairy; anthers sagittate, to 3.5 mm long. Ovary ovoid, 1 mm long, superior, glabrous, 7–9 locued; ovule 1 in each locule; style subulate, 1.6–1.8 cm long, pale green, glabrous; stigma pointed. Berries ovoid, ca. 2.0 × 1.0– 1.5 cm with persistent style 1.6–1.8 cm long, glabrous; fruit pedicel 2.2–2.5 cm long. Seed 1, ellipsoid, 1.2–1.3 × 0.6–0.7 cm, laterally compressed, brown, shining.

Flowering and Fruiting: —January to May

Habitat, Ecology and Conservation status: —The type locality of this species was part of the once existed riparian vegetation and is partially converted now for agricultural purposes. The main associated species are Artocarpus hirsutus Lamarck (1789:211) , Holigarna arnottiana Hooker (1879:36) , Hopea parviflora Beddome (1864: 31) , Lannea coromandelica ( Houttuyn 1774: 39) Merrill (1938:353) , Mangifera indica Linnaeaus (1753: 200) and Vateria indica Linnaeaus (1753: 515) . The present population consists of three mature trees and several seedlings of various ages occupying an area of less than 1 km 2. Following the IUCN Redlist criteria ( IUCN 2020), Madhuca balakrishnanii is assessed as Critically Endangered (CR) in the category [B2a, b(v)].

Distribution: —Endemic to Kerala

Etymology: —The new species is named after Late Mr. Balakrishna Pillai (Madathinal Thekkathil, Muzhangodi, Karunagappally, Kollam, Kerala) who preserved this tree species in his premises as ‘star tree’ for several years.

Additional Specimens examined: — INDIA, Kerala, Kollam District, Thodiyur Panchayat, Mararithottam-Muzhangodi , 40 m., 4 March 2021, E.S. Santhosh Kumar, S. Shailajakumari & S.M. Shareef 92430 (Paratype TBGT!) .