Eugenia echinulata N. Snow, 2015

Snow, Neil, Callmander, Martin & Phillipson, Peter B., 2015, Studies of Malagasy Eugenia - IV: Seventeen new endemic species, a new combination, and three lectotypifications; with comments on distribution, ecological and evolutionary patterns, PhytoKeys 49, pp. 59-121 : 65-68

publication ID

https://dx.doi.org/10.3897/phytokeys.49.9003

persistent identifier

https://treatment.plazi.org/id/E8F0EF18-CCB2-D8B3-B83A-48B77AA59AE0

treatment provided by

PhytoKeys by Pensoft

scientific name

Eugenia echinulata N. Snow
status

sp. nov.

Eugenia echinulata N. Snow sp. nov. holotype (Figure 9): http://www.tropicos.org/Image/100314922; living material: http://www.tropicos.org/Image/100306108

Haec species inter congeneros madagascarienses fructibus maturis valde echinulatis distinguitur.

Type.

Madagascar. Prov. Toamasina: zone d’occupation controlée d’Antenina, sur piste entre Antenina et Ankosy, à 2 km du village d’Antenina, 17°30'00 ’’ -17°29'47"S, 48°46'19"E-48°45'35"E, 917 m, 1 Feb. 2002, L.M. Randrianjanaka 702 + N.M. Andrianjafy (holotype: MO-5786207!; isotypes: P, TAN).

Description.

Shrubs or trees 1.5-4 m tall; dbh 4-5 cm; bark of main bole brown, somewhat cracking. Foliage and flowers glabrous except as noted. Branchlets terete to laterally compressed, drying light brown to gray, smooth, oil glands occasional but barely visible. Leaves slightly discolorous, more or less evenly distributed, margins coarsely sinuous, venation brochidodromous, surfaces matte. Axillary colleters absent. Petioles 4-6 mm long, slightly suclate, eglandular. Leaf blades (3.0-)3.8-6.5 × (1.0-)1.6-3.5 cm, narrowly elliptic or narrowly ovate to elliptic, base cuneate, apex acute to acuminate; adaxial midvein sulcate proximally but becoming flush distally, oil glands dense but faint, sometimes protruding slightly on dried material; abaxial surface midvein prominently raised, oil glands common to dense and of uniform size but faint, sometimes slightly protruding (dried material). Inflorescence ramiflorous or axillary. Flowers solitary or clustered into short brachyblasts; brachyblasts 2-5 mm long, densely short-bracteolate, sparsely covered with twisted, whitish-maroon trichomes. Pedicles 5-7.5 mm, glabrous. Flower material scant. Hypanthium ca. 3 mm, coarsely large-pustullate (warty), light green or yellowish-green in bud. Calyx lobes 4 (rose-colored in bud), 3-4 mm, elliptic to broadly ovate or rounded, glabrous, mostly persisting and crowning fruit. Petals not seen; said to be pink (Antilahimena 8858). Stamens not seen; anthers said to be yellow with white filaments (Ahtilahimena 8858). Style not seen. Berry 1.3-1.8 × 1.0-1.5 cm, globose to subglobose, coarsely rugose-warty when fresh but drying echinulate (with with short sharp points), densely glandular when younger, green when immature, drying nearly black. Seeds in mature fruit 1; ca. 10-11 mm, globular, outer seed coat elgandular.

Etymology.

The specific epithet comes from the Latin echinulatus (having very small prickles) in reference to the prickly, dried, mature fruits that are unique for the genus in Madagascar.

Vernacular name.

Rotra (Antilahimena 6841).

Phenology.

Flowering December; fruiting January and February.

Distribution.

Known from the eastern escarpment of Madagascar in the Toamasina Province around Analamazaotra and Ambatovy and in the highlands at Anjozorobe in Antananarivo Province (Fig. 7).

Habitat and ecology.

Dense humid evergreen forests; ca. 915-1350 m.

Conservation status.

One collection indicated the species as being abundant in its area of collection (Randrianaivo 1463 et al.). However, with an EOO of 4,372 km2, an AOO of 72 km2 and three subpopulations, two of which are situated within the protected area network (Analamazaotra, Zahamena), Eugenia echinulata is assigned a preliminary risk of extinction of “Vulnerable” [VU B1ab(iii)+2ab(iii)] following the IUCN Red List Categories and Criteria ( IUCN 2012).

Specimens examined.

MADAGASCAR. Prov. Antananarivo: Reg. Analamanga, Anjozorobe, Ambongamarina, Ampamoa, à 10 km au Nord-Est d’Anjozorobe, prolongement N de la fôret d’Antsahabe, 18°23'19"S, 47°55'49"E, 1352 m, 15 Feb. 2007, R. Randrianaivo 1463 + L. Vary, François, Jacques & Rakoto (MO-6440448). Prov. Toamasina: Alaotra-Mangoro, Fkt: Menalamba, Ambatovy, 1168 m, 18°50'11"S, 48°18'44"E, 22 Jan. 2007, P. Antilahimena 5170 et al. (MO-5786207, KSP [KSP000006], P [P00730617]); ibid. loc., 18°52'25"S, 48°20'44"E, 979 m, 4 Oct. 2008, P. Antilahimena 6566 et al. (MO, P, TAN); ibid. loc., 18°52'28"S, 48°17'37"E, 1010 m, 10 Nov. 2008, P. Antilahimena 6841 + M. Ratolojanahary, B.A. Ratodimanana, M. Randrianarivony, M. Ratovomanana & F. Edmond (MO, P, TAN); ibid. loc., 18°52'30"S, 48°17'35"E, 970 m, 10 Nov. 2008, P. Antilahimena et al. 6854 (MO, P, TAN); ibid. loc., 18°55'22"S, 48°25'39"E, 1013 m, 21 Dec. 2013, Antilahimena 8858 + Rabarison, Honoré, Félix, Randrimitantsoa Jean & V. Razafindrahaja (MO, P, TAN); Phelps Dodge project site, ca. 15 air-km NE of Moramanga, ca. 11 km E of Antanambao. Ambatovy, SE valley (Ambohimanga), 18°51'34"S, 48°18'25"E, 1050 m, P.J. Rakotomalaza 1208a (MO, P [P00730620]); Analamazaotra, Ambatovy, 18°56'10"S, 48°25'33"E, 11 Dec. 2013, Ramahenina 276 et al. (MO); Ambatovy, forêt de Savihara, 18°52'06"S, 48°16'43"E, 22 Feb. 2010, D. Razafimelison 10 et al. (P [P00730618]); Alaotra-Mangoro, Moramanga, Andasibe, Réserve Spécial d’Analamazaotra, Circuit Indri 1, 18°56'20"S, 48°25'09"E, 947 m, 14 Dec. 2013, H.M.J. Rasoazanany 541 + H. Razafindraibe, B. Ramandimbisoa & Rakotondravelo (MO, P, TAN).

Comments.

Eugenia echinulata is unknown in flower apart from one remnant hypanthium on the holotype. However, the coarsely sinuate leaf blades and acuminate apices, coupled with the warty mature fruits, are diagnostic and unknown in combination elsewhere among Malagasy congeners. Whereas Eugenia muscicola H. Perrier has narrowly elliptic leaves, its leaf margins are more or less planar. A number of similar sterile collections from this area may be this taxon.

The texture of the fruit is coarsely rugulose-warty (see link above to image of living material), but the warty protrusions collapse to a large extent and upon drying and then assume a sharper, echinulate texture.

Kingdom

Plantae

Phylum

Tracheophyta

Class

Magnoliopsida

Order

Myrtales

Family

Myrtaceae

Genus

Eugenia