Xylopia australis D. M.Johnson & N. A.Murray

Johnson, David M. & Murray, Nancy A., 2020, A revision of Xylopia L. (Annonaceae): the species of Madagascar and the Mascarene islands, Adansonia 42 (1), pp. 1-88: 44-45

publication ID

http://doi.org/ 10.5252/adansonia2020v42a1

DOI

http://doi.org/10.5281/zenodo.3883324

persistent identifier

http://treatment.plazi.org/id/417D87A4-FFD0-FFC2-FE8A-572D31A9F84C

treatment provided by

Tatiana

scientific name

Xylopia australis D. M.Johnson & N. A.Murray
status

 

13. Xylopia australis D. M.Johnson & N. A.Murray   , sp. nov. ( Figs 15L-U View FIG ; 16A, G View FIG )

One of a group of Xylopia   species in Madagascar with short broad petals and clavate stigmas, distinguished by the strongly raised reticulation of the leaves, the secondary veins often joining to form a sinuous intramarginal vein, the narrowly oblong or elliptic-oblong to lanceolate shape of the leaf blades, the corrugated adaxial surface of the inner petals, and the oblong glaucous and glabrate monocarps.

TYPE. — Madagascar. Prov. Toliara, Préfecture de Taolagnaro [“ Tôlanaro ”] ( Fort-Dauphin ), Petriky forest , c. 15 km WSW of Taolagnaro [“ Tôlanaro ”] ( Fort Dauphin ), 25°04’S, 46°51’E, 0-10 m, 9.III.1989 (fl.), Schatz et al. 2641 (holo-, MO!; GoogleMaps   iso-, BR!; K!; WAG!).

PARATYPES. — Madagascar. Prov. Toliara, forêt de Vinanibe près Fort-Dauphin, 5-50 m, 2.IV.1947 (fl.), Humbert 20767 (P)   ; Région de l’Anosy, Bemangidy Forest, c. 3 km W of Antsotso, along RN 12a, 65 km N of Ft. Dauphin , E of Ivohibe peak, 24°35’02”S, 47°12’44”E, 100-250 m, 7.II. 2006 (fl.), Lowry et al. 6669 ( MO) GoogleMaps   ; Anosy Region, ouest du village Malana, vers sommet entre Andohavola et Tanimena, FKT: Farafara Vatambe, CR: Mahatalaky, Dist.: Taolagnaro , Rég.: Anosy, 24°51’22”S, 47°00’27”E, 411 m, 16.XI.2009 (fl., fr.), Rakotovao et al. 4575 ( MO) GoogleMaps   ; Fiv. Fort Dauphin, Com. Ampasinampoa, Fkt. Analambendrana à 4 km (vol d’oiseau) à l’ouest d’Ampasinapoa, 24°59’06”S, 46°57’37”E, 400 m, 24.XI.2002 (fr.), Randrianaivo et al. 838 ( MO) GoogleMaps   ; Anosy Region, Fort-Dauphin, Iaboko, Antsotso, Forêt Ivohibe , 24°34’14”S, 47°12’04”E, 265 m, 28.XI.2005 (fr.), Razakamalala et al. 2414 ( MO, P[P06901342]) GoogleMaps   ; Anosy Region, Taolagnaro, Iaboko, Antsotso Avaratra, 24°34’16”S, 47°12’06”E, 271 m, 8.XII.2007 (fr.), Razakamalala et al. 3797 ( MO, P[P06490487]) GoogleMaps   .

DISTRIBUTION, ECOLOGY AND CONSERVATION STATUS. — Xylopia australis   , sp. nov., is restricted to a small area in southeastern Madagascar, where it occurs in humid forest, sometimes on forested dunes or sand, at elevations from sea level to c. 400 m ( Fig. 28 View FIG ). Specimens with flowers have been collected from February to April and in November, and with fruits in November and December. With its small EOO and AOO values, 185 km 2 and 24 km 2, respectively, X. australis   , sp. nov., is given a preliminary conservation assessment of Endangered ( Table 2). Several of the collections come from the general area of the Tsitongambarika forest, an area of high endemism ( Razakamalala et al. 2011), which was designated as a protected area in 2015. The forests there are tropical in structure ( Goodman et al. 1997) but lie south of the Tropic of Capricorn.

LOCAL NAME. — Ovaria (Rakotovao et al. 4575).

DESCRIPTION Tree or shrub up to 8 m tall; d.b.h. up to 10 cm.

Twigs glabrous to sparsely pubescent, the hairs 0.2-0.4 mm long, soon glabrate; nodes with a single axillary branch.

Leaves with larger blades 8.7-17.2 cm long, 2.2-4.4 cm wide, subcoriaceous, discolorous, light gray to grayish green adaxially, orange-brown to brown abaxially, or concolorous, narrowly oblong or elliptic-oblong to lanceolate, apex acute to acuminate, the acumen 4-20 mm long, base rounded to broadly cuneate, short-decurrent on petiole, margin slightly revolute, glabrous adaxially, sparsely and finely appressedpubescent abaxially, the hairs sometimes restricted to the midrib; midrib pale yellow to brown or concolorous with blade adaxially, secondary veins distinctly brochidodromous, forming a wavy intramarginal vein, 14-17 per side, diverging at 60-90° from midrib, these and higher-order veins strongly raised and forming a conspicuous reticulum on both surfaces; petiole 2-9 mm long, shallowly canaliculate to semi-terete, transversely wrinkled and longitudinally striate, glabrous to sparsely pubescent.

Inflorescences axillary, 1-flowered, not pedunculate, sparsely appressed-pubescent; pedicels 4.7-6.5 mm long, 1.1-1.6 mm thick; bracts 3, evenly spaced along pedicel, caducous or persistent, 2.3-2.7 mm long, triangular; buds ovoid to oblong, apex obtuse.

Sepals somewhat spreading at anthesis, ¼-1/3-connate, 3-4.7 mm long, 3.9-4.5 mm wide, coriaceous, broadly triangular, apex acute, appressed-pubescent abaxially.

Petals pale yellow to creamy white, the inner petals also red at the base in vivo; outer petals spreading at anthesis, 11-18.8 mm long, 3-5.9 mm wide at base, 4.9-5.7 mm wide at midpoint, fleshy, oblong-lanceolate to oblong-ovate, flattened and some- what concave but keeled at apex adaxially, not keeled abaxially, apex obtuse, pubescent toward apex and glabrous toward base adaxially, appressed-pubescent abaxially; inner petals erect at anthesis, 13.1-15.2 mm long, 2.5-3.9 mm wide at base, 2.0- 2.4 mm wide at midpoint, fleshy, lanceolate, keeled at apex, flat and corrugated in center adaxially, keeled abaxially, apex acute, base shallowly concave with undifferentiated margin, puberulent on distal ¼ on both surfaces.

Stamens 200-250; fertile stamens 1.4-1.8 mm long, narrowly oblong, anther connective apex 0.2-0.4 mm long, shield-shaped, overhanging anther thecae, papillate, anthers 7-11-locellate, filament 0.3-0.4 mm long; outer staminodes 1.4-1.7 mm long, oblong, apex obtuse; inner staminodes 1.4-1.7 mm long, clavate to oblong, apex obtuse; staminal cone 2.7-3.1 mm in diameter, 1.6-2.0 mm high, completely concealing the ovaries, rim irregularly laciniate.

Carpels 5-7; ovaries c. 1.3 mm long, narrowly oblong, pubescent, stigmas free or loosely connivent, 2.6-2.9 mm long, clavate and somewhat falciform, sparsely pilose.

Fruit of up to 5 monocarps borne on a pedicel 4.5-7.3 mm long, 2.5-3.3 mm thick, pubescent; torus 4.7-5.7 mm in diameter, 4.5-5.0 mm high, ovoid to globose; monocarps with glaucous-green exterior in vivo, 2.9-5.3 cm long, 1.3-2.0 cm wide, 1.2-2.0 cm thick, ovoid to oblong, sometimes weakly torulose, apex rounded or with a blunt beak 2-4 mm long, base sessile or contracted into a stipe 3-5 mm long, 4-6 mm thick, finely verrucose and wrinkled, with a glaucous bloom, dull to slightly shiny, glabrate; pericarp 0.4-1 mm thick.

Seeds up to 4 per monocarp, in a single row, lying oblique to nearly perpendicular to long axis, 12-14.4 mm long, 9-10.3 mm wide, c. 9.5 mm thick, ellipsoid to broadly ellipsoid, somewhat quadrangular in cross-section, light brown, wrinkled and pitted, dull, perichalazal ring visible as a slightly raised line; sarcotesta not detected; aril absent.

NOTES

Xylopia australis   , sp. nov., is readily identifiable by its relatively large, but narrow, long-acuminate subcoriaceous leaves, with the higher-order venation raised and forming a conspicuous reticulum on both surfaces. The secondary veins frequently unite to form a wavy intramarginal vein. The corrugated surfaces of the inner petals and the glaucous monocarps are unique characters among Madagascar Xylopia   species. This southern distribution of the species in Madagascar is the basis for the specific epithet. The collection Lam & Meeuse 6013 (L, WAG), Tamatave, Rés. Nat. Betampona, 450 m, 19.XII.1938 (fr.), bears monocarps that resemble those of X. australis   , sp. nov., in the blunt apex, the glabrate surface, and the small number of large seeds. The leaves differ from those of X. australis   , sp. nov., in being elliptic to obovate, smaller (up to 9.4 cm long), and chartaceous in texture. The monocarps are distinctly stipitate, with a flat truncate apical beak. It has not been re-collected, despite recent plant inventory efforts in the Betampona Reserve.

MO

Missouri Botanical Garden