Eugenia iantarensis 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 : 71

Eugenia iantarensis N. Snow sp. nov. holotype (Figure 13): http://www.tropicos.org/Image/100314910; living material: http://www.tropicos.org/Image/100146017

Haec species a congeneris madagascariensibus foliis abaxialiter secus costae partem proximalem glandulis oleiferis manifestis ornatis, fructu permagno atque seminibus testa externa profunde sulcata convolutaque distinguitur.

Type.

MADAGASCAR. Prov. Fianarantsoa: Andringitra, Camp I, ca. 45 km S of Ambalavao, east bank of Iantara River, along Ambalamanenjana-Ambatomboay trail, edge of Andringitra Reserve, 22°13'20"S, 47°01'29"E, 20 m, 15-21 Nov. 1993, B. Lewis 776 + J. Raharimalala, G. Rahajasoa, M. Randriambololona & J. McDonagh (holotype: MO-6224855!]; isotypes: KSP [KSP000052]!, P, TAN).

Description.

Shrubs or trees, 3-9 m tall; dbh 6-10 cm; bark of main bole unknown. Vegetative and reproductive parts glabrous or (as noted) moderately to densely sericeous (trichomes dibrachiate and ferrugineous). Branchlets somewhat compressed laterally but becoming terete, becoming irregularly wrinkled in age, oil glands common, prominent and somewhat protruding initially but fading with age, grayish brown. Leaves concentrated mostly at branchlet tips, only 1-2 leaves produced during seasonal growth, the pairs ca. 1-1.5 cm distant; blades coriaceous, venation brochidodromous, surface and margin flat or slightly sinuous, somewhat discolorous, matte above and below. Axillary colleters absent. Petioles 6.5-10.5 mm long, rounded above, eglandular, shedding an outer (grayish or light brownish) epidermal layer with age. Leaf blades (9)11.5-22 × (3.4)5-8.7 cm, elliptic (or infrequently narrowly elliptic, narrowly obovate or obovate), base cuneate, apex obtuse; adaxial surface oil gland dense, easily seen with magnification, midvein sulcate but becoming flush apically, secondary veins protruding slightly; abaxial surface sparsely to moderately sericeous (hairs dibrachiate, ferrugineous) but becoming glabrous, oil glands common (notably less dense than adaxial), midvein protruding (and with punctate glands, especially proximally), punctate, striate, secondary veins somewhat protruding (moreso than on adaxial surface), intramarginal vein connecting tips of secondaries arching moderately, 1.5-3.3 mm from margin at laminar midpoint. Inflorescence of terminal, axillary or ramiflorous monads, solitary to paired or occasionally in few-flowered fascicles. Pedicels 8-21 mm long (in fruit), 1.8-3.5 mm wide, round in transverse section, rigidly stiff, ascending, sparsely hairy (use high magnification) or evidently glabrous, eglandular, somewhat striate, the epidermis reddish and eventually cracking in small irregular flakes, anthopodia and metaxyphylls lacking. Bracteoles (only one seen) evidently broadly triangular, ca. 2 mm long. Calyx lobes 4, 5.5-8.8 mm long, broadly rounded, apex obtuse, hairy towards based but otherwise more or less glabrous adaxially, moderately to densely hairy abaxially, bifacially glandular, persisting in fruit and tearing somewhat beneath the based as fruit matures, green to cream-colored or magenta above. Petals violet (Ratolojanahary 88). Staminal disk (in mature fruit) 7-16 mm wide, glabrous. Stamens (estimated from basal scars) 150+. Style (material scant) ca. 9 mm long, glabrous; stigma narrow (scarcely if at all capitate). Ovary 2-locular; placentation axile; ovules up to 5 per locule and radiating from central position. Berries 3.2-4.1 × (1.6)2.4-5.0 cm, irregularly globose and often with 3-numerous irregular lobes (from maturing seeds), densely shortly sericeous, pale green immature becoming grayish-brown when fresh but drying light rusty-brown by virtue of indumentum, outer wall embedded with numerous straight, more or less evenly spaced vertical veins extending between base and apex. Seeds 3-15 per fruit (up to 8 per locule), 17-25 mm long, up to ca. 15 mm thick (shrinking considerably away from seed coat during drying), radiating out from placenta (narrowed towards attachment point); seed coat thickly membranous to somewhat leathery, eglandular, separating easily from embryo, surface drying irregularly bullate, light reddish brown; cotyledons evidently completely fused.

Etymology.

The specific epithet is a Latinization of the Iantara River, location of the type gathering.

Vernacular names.

Rotramena vaventiravina (Kotozafy 922); rotra (Antilahimena 6914).

Phenology.

Flowering March through November; fruiting November and December.

Distribution.

Known from the eastern escarpment of Madagascar in Finarantsoa and Toamasina provinces around and in the Andringitra, Ranomafana and Analamazaotra Special Reserve (Fig. 11).

Habitat and ecology.

Evidently along or near rivers in humid forest, sometimes in disturbed areas; from 770-1210 m. The type collection indicates the plant, presumably the large fruits, is used by the Common brown lemur, Eulemur fulvus .

Conservation status.

With an EOO of 4,892 km2, an AOO of 81 km2 and three subpopulations, all of which are situated within the protected area network (Andringitra, Ranomafana and Analamazaotra), Eugenia iantarensis is assigned a preliminary status of "Least Concern" [LC] following the IUCN Red List Categories and Criteria ( IUCN 2012).

Comments.

The flowering and early fruiting material (Toamasina Province) and mature fruiting material (Finarantsoa) are disjunct and the flowering material is somewhat incomplete (no petals), but apart from slightly shorter leaves in Toamasina the specimens match well.

Mature fruits are among the largest yet known among Malagasy Eugenia , and the large number of seeds per fruit (up to 13) is considerably greater than that commonly seen for Eugenia worldwide or in Madagascar. The testa in dried material becomes highly furrowed-convoluted to resemble the surface of a human brain, likely due only in part to shrinkage from dessication. A similar testal morphology was recently described in Eugenia alletiana Baider & Florens from Mauritius ( Baider and Florens 2013), although the testa of that species at maturity was said to be as firm as the texture of wood. The selective pressures underlying the evolution of such a thick and tough testa are worthy of consideration in light of the observation on the holotype label that the trees are used by brown lemurs. The walls of the fruit and testa frequently have bore holes of an unknown insect of ca. 2 mm diameter.

Specimens examined.

MADAGASCAR. Prov. Fianarantsoa: Parc National de Ranomafana, 21°15'S, 47°25'E, 1045 m, 5 Dec. 2007, J. Renoult Ma07-225 (P [P05208539]); Parc National de Ranomafana, Parcelle II d’Ambodiamontana, Parcelle II de Talatakely, 21°16'S, 47°26'E, 950 m, 14 Mar. 1995, A. Kotozafy 922 (KSP [KSP000050, KSP000051], MO-04940615, P [P05208460]); Andringitra RN. Ivohibe, à l’W d’Ambarongy, au NE du campement no. 3, sur la piste à l’E du campement no. 3 vers le campement no. 4, 22°13'22"S, 46°58'18"E, 1210-1625 m, 8-11 Dec. 1994, C. Rakotovao 287 (MO-6224856, MO-5474705 [carpo.], P [P04884880]). Prov. Toamasina: Ampitambe, Ambatovy, Sahaviara forest, 18°52'19"S, 48°16'43"E, 1035 m, 9 Nov. 2005, P. Antilahimena 4143 & F. Edmond (MO, P [P05094984]); Ampitambe, Ambatovy, 18°51'39"S, 48°16'27"E, 943 m, 15 Dec. 2005, P. Antilahimena 4384 (MO, P [P00730616]); Ambatovy, Antaralava Besalampy forest, 18°53'15"S, 48°16'09"E, 950 m, 15 Nov. 2008, Antilahimena 6905 (MO-6447003, P [P00730615]); Ambatovy, Sahaevo, 18°50'26"S, 48°16'3"E, 982 m, 23 Nov. 2008, P. Antilahimena 6914 + B.A. Ratodimanana, D. Ravelonarivo, E. Félix & M. Ratovomanana (MO-6447031); Fkt: Ambohibolakely, forêt d’Amparihy, corridor Forestier Analamay Mantadia, 18°47'28"S, 48°22'46"E, 1001 m, 23 Apr. 2012, C. Rakotovao 5783 (P [P00730613]); Ampitambe, Ambatovy, forêt d’Ampadidifanantsy, 18°51'46"S, 48°16'32"E, 975 m, 27 Oct. 2008, M. Ratolojanahary 88 (MO-6453743, P [P04680790]); Forêt d’Analamazaotra, [18.56'S, 48.26'E], 3 Dec. 1934, Ursch 20 (P [P05208538]).