Acalypha linearifolia Leandri
Creators: name: Muñoz, Iris Montero
name: Levin, Geoffrey A.
name: Cardiel, José María
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Malpighiales
Euphorbiaceae
Acalypha
Acalypha linearifolia

description: 31. Acalypha linearifolia Leandri   
 Notulae Systematicae. Herbier du Muséum de Paris. Phanérogramie. Paris 10: 275 (Leandri 1942). — Type: Madagascar. Prov. Toliara, Ambovombe, Kotoala, 21.I.1931, R. Decary 8423 (lecto-, designated by Montero Muñoz et al. [2018a: 103]: P[P00513090]; isolecto-, S[S07-14664],TAN[TAN000510], US [US 01014148]). — Former syntype: Madagascar. Prov. Toliara, delta de la Linta, 17-24.VIII.1928, H. Humbert & C. F. Swingle 5385 (P[P00513086, P00513087, P00513088, P00513089], US [US 00096361]).   
ICONOGRAPHY. — Leandri (1942: 276); Fig. 57C.  
ETYMOLOGY. — The specific epithet refers to the linear leaf blades characteristic of this species.  
DISTRIBUTION AND HABITAT. — Endemic to Madagascar (Atsimo-Andrefana, Androy, and Atsinanana [one known collection]). Littoral forest and littoral thicket. On unconsolidated sand and Tertiary limestone. Altitudinal range sea level to 10 m (Fig. 50).  
 PRELIMINARY CONSERVATION ASSESSMENT. — Acalypha linearifolia is known from five collections. Its EOO is estimated to be 84 834 km 2 and its AOO 16 km 2. The large EOO is due to one collection presumably made in Toamasina by G. Cours. The other collections are from southern Madagascar. This species grows mainly in littoral forests (see assessment of A. gracilipes). There are no collections made in protected areas. In addition, no specimens of this species have been collected for 70 years, so we cannot rule out that this species has become extinct. Due to habitat loss and the absence of recent collections, A. linearifolia is assigned a preliminary conservation status of Endangered: EN B2ab(ii,iii,iv); although it meets the values needed for a threatened category based on the B2 subcriterion, this species could probably be assessed as extinct (EX).   
 MATERIAL EXAMINED. — 4 collections. Madagascar: Cours, G. 4637 (P[P00324458, P00513085]), 4638 (G, P[P00513084]); Decary, R. 8423 (P[P00513090], S[S07-14664], TAN[TAN000510], US[US01014148]); Humbert, H. 5385 (P[P00513086, P00513087, P00513088, P00513089], US[US00096361]).   
 REFERENCES. — Govaerts et al. (2000: 72); Montero Muñoz et al. (2018a: 103).   
DESCRIPTION  
 Shrubs, probably evergreen, to 1.5 m tall, monoecious. Branches densely pubescent with stellate trichomes, glabrescent when mature. Axillary buds ovoid, to 1 × 0.7 mm, perulate, perules 2, valvate, membranous, brownish, pubescent with stellate trichomes; Stipules to 1 mm long, lanceolate, pubescent with stellate trichomes, margin with some sessile glands. Petioles to 0.2 cm long, indumentum similar to that on young branches. Leaf blades ericoid, 3.5-4.7 × 0.1-0.2 cm, linear, coriaceous; base acute; apex obtuse to rounded; margin entire, revolute; upper and lower surfaces densely pubescent with stellate trichomes; venation prominent on lower surface, pinnate, secondary veins to 15 per side. Stipels absent. Inflorescences spiciform, male, and solitary female bracts, axillary. Male inflorescences to 1.4 cm long, with glossy exudate; subsessile, peduncle to 2 mm long, pubescent with stellate trichomes; flowers glomerate; bracts orbicular, to 0.5 mm diameter, pubescent with stellate trichomes. Solitary female bracts subsessile, peduncle to 2 mm long, pubescent with stellate trichomes; bract short-petiolate, enlarging in fruit to 4 × 5 mm, suborbicular, densely pubescent with stellate trichomes; margin entire to denticulate, central tooth not prominent; bracteoles absent. Male flowers: pedicel to 0.5 mm long, glabrous; buds to 0.5 mm diameter, pubescent with stellate trichomes. Female flowers 1 per bract, sessile; sepals 3, to 1 mm long, ovate-lanceolate, pubescent with stellate trichomes; ovary c. 1 mm diameter, 3-lobed, papillose, surface pubescent with stellate trichomes; styles not seen. Allomorphic flowers not seen. Capsules to 3 mm diameter, papillose, surface pubescent with stellate trichomes. Seeds c. 2 × 1.8 mm, subglobose, minutely foveolate.
description: Published as part of Muñoz, Iris Montero, Levin, Geoffrey A. & Cardiel, José María, 2023, Monograph of Acalypha L. (Euphorbiaceae) of the Western Indian Ocean Region, with the description of a new species from Mayotte, pp. 395-496 in Adansonia (3) (3) 45 (26) on page 458, DOI: 10.5252/adansonia2023v45a26, http://zenodo.org/record/10209220