Xylopia longirostra D.M.Johnson & N.A.Murray, 2020

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 : 73-74

29. Xylopia longirostra D.M.Johnson & N.A.Murray , sp. nov. ( Fig. 25A-E )

Species resembling Xylopia ambanjensis and X. lastelliana in the lanceolate leaves under 9 cm long with acuminate apices, but differing from both in the leaf acumen forming 1/4-1/5 rather than 1/6-1/8 of the leaf length. It additionally differs from X. ambanjensis in the subcoriaceous rather than chartaceous leaves, the absence of persistent hairs along the leaf margins, and the mature monocarps larger, 3.8-5 cm long, and more prominently lenticellate. From X. lastelliana it differs in the sparsely appressed-pubescent rather than densely sericeous abaxial leaf surfaces.

TYPE. — Madagascar. Prov. Toamasina, Vohibola, forest N to NNW of village of Andranokoditra , N of Lac Ampitabe, 18°33’34”S, 49°15’17”E, 5 m, 12.II.2003 (fr.), Lowry et al. 6064 (holo-, MO!; iso-, OWU!, P[P01987028]!).

PARATYPES. — Madagascar. Prov. Toamasina, Analanjirofo Region, Vavatenina , Sahatavy, Sahalangina, forêt d’Anjirobe, 17°28’02”S, 48°54’23”E, 550 m, 26.X.2000 (buds), Andrianjafy et al. 120 ( MO) ; à Ambila-Lemaitso , 14.XII.1967 (fr.), Capuron 28035 SF (K, P[P01987026] ; Foulpointe , 22.I.1973 (st.), Debray 1974 (P[P02034676, P02034677]) ; Fivondronana: Brickaville, Firaisana : Ambinaninony , Fokontany : Andranokoditra , forêt littorale sur sable du label Conservation Biodiversité Développements ( CBD) à Vohibola , 18°34’50”S, 49°15’16”E, 10 m, 8.XII.2001 (fr.), Rabenantoandro et al. 854 (K, MO, P[P01987029]) ; Analanjirofo Region, Fivondronana Vavatenina, Commune Ambodimangavalo , limite du Parc national de Zahamena, 17°33’41”S, 48°54’14”E, 850 m, 2.V.2003 (immature fr.), Rakotonandrasana et al. 682 ( OWU, P[P01954127]) ; Fivondronana: Brickaville, Firaisana : Ambinaninony , Fokontany : Andranonkoditra , forêt littorale de Vohibola, 18°33’55”S, 49°15’22”E, 3 m, 24.X.2002 (fr.), Razakamalala 266 (K, MO, NY) .

DISTRIBUTION, ECOLOGY AND CONSERVATION STATUS. — Five of the seven collections of X. longirostra , sp. nov., were made in the Vohibola coastal littoral forest area of east-central Madagascar, where the species occurs with X. retusa , sp. nov., another near-endemic to the area and two more widespread Xylopia species, X. buxifolia and X. humblotiana . Two incomplete specimens of X. longirostra , sp. nov., have also been collected from humid forest on low summits inland at elevations of 550 and 850 meters ( Fig. 29 ). A specimen with flower buds was collected in October, and the specimens with fruits were collected in February, May (immature), October, and December. The EOO of 5003 km 2 and AOO of 24 km 2 lead to a preliminary conservation assessment of Endangered ( Table 2 ).

LOCAL NAME. — Ankahatra madinika lava ravina (Rakotonandrasana 682), hazoambo (Andrianjafy et al. 120).

DESCRIPTION Tree up to 12 m tall; d.b.h. up to 20 cm.

Twigs glabrous or sparsely pubescent, the hairs 0.1-0.4 mm long, soon glabrate; nodes with one or often two axillary branches.

Leaves with larger blades 4.9-7.0 cm long, 1.3-1.7 cm wide, subcoriaceous, slightly discolorous, brown-olive adaxially, light brown abaxially, lanceolate to oblong-lanceolate, apex acuminate, the acumen 9-16 mm long, base cuneate, short-decurrent on petiole, margin slightly recurved, glabrous adaxially, sparsely appressed-pubescent abaxially; midrib reddened toward base adaxially, secondary veins weakly brochidodromous, 11-13 per side, diverging at 50-70° from midrib, these and higher-order veins slightly raised on both surfaces; petiole 3-5.5 mm long, canaliculate, slightly wrinkled, glabrate or with a few hairs.

Inflorescences axillary from the axils of newly expanding shoots, 1-flowered, not pedunculate, sparsely pubescent; pedicels [probably not fully elongated] 1.8-2.5 mm long, c. 0.7 mm thick; bracts 2, both attached near the pedicel midpoint, persistent [but flowers immature], 0.9-1.2 mm long, broadly ovate to semicircular; buds lanceolate, apex acute.

Sepals with position at anthesis unknown, ¹⁄5-1/3-connate, c. 1.3 mm long, c. 1.6 mm wide, coriaceous, ovate to broadly triangular, apex acute, margins ciliate and with a few sparse hairs abaxially.

Petals, stamens, and carpels unknown.

Fruit of up to 4 monocarps borne on a pedicel 4-7 mm long, 3.5-4.5 mm thick, glabrate; torus 5.5-10 mm in diameter, 6-7 mm high, depressed-globose; monocarps with orange yellow to red exterior in vivo, 3.8-5.0 cm long, 2.3-2.4 cm wide, 2.3-2.6 cm thick, ellipsoid to ovoid, not torulose, apex rounded, base sessile or occasionally contracted into a stipe 3.5-4 mm long, 5.5-9 mm thick, verrucose, longitudinally wrinkled, conspicuously marked with raised lenticels, dull, glabrate; pericarp c. 2.1 mm thick.

Seeds c. 10 per monocarp, in two rows, perpendicular to long axis, 18.7-19.6 mm long, 10.7-11.4 mm wide, 8.5-9.2 mm thick, oblong-ellipsoid, broadly wedge-shaped in cross-section, chestnut brown, smooth, slightly shiny, perichalazal ring not evident; presennce of sarcotesta undeterminable; aril absent.

NOTES

Xylopia longirostra , sp. nov., has relatively small narrow leaves similar to those of X. ambanjensis , but the leaves are subco- riaceous and shiny adaxially and, as indicated by the specific epithet, have an acumen forming a greater proportion of the total blade length, about ¼-¹⁄5 rather than ¹⁄6-1/8. The leaves are also less hairy than those of X. ambanjensis , lacking the persistent hairs along the midrib and leaf margins. The monocarps of X. longirostra , sp. nov., are prominently lenticellate and much larger than those of X. ambanjensis , with seeds over 18 mm long. The lenticels are often prominent on the twigs as well, giving them a bumpy appearance. Another character that X. longirostra , sp. nov., and X. ambanjensis have in common is that the leaf acumen is wrapped around itself early in development and sometimes remains that way in mature leaves ( Fig. 25B ). Xylopia lastelliana resembles X. longirostra , sp. nov., in its leaf shape and fruit morphology, and occurs in similar localities in a comparable range of elevations. Xylopia longirostra , sp. nov., is readily distinguished from X. lastelliana , however, by the absence of sericeous leaf indument on the leaves as well as by the longer and more abrupt leaf acumen.

The specimens Andrianjafy et al. 120 and Rakotonandrasana 682 were collected some distance from the coast and slightly north of the forests where the other specimens were collected, but the leaves are identical in shape and texture. One of these specimens has only flower buds, while the other has only immature fruits, which limits additional comparisons.

Figures

FIG. 25. — Xylopia longirostra, sp. nov., and X. marojejyana, sp. nov. A-E, X. longirostra, sp. nov.: A, habit; B, close-up of rolled apex of developing leaf; C, immature flower bud, side view; D, monocarp, side view; E, seed, side view. F-H, X. marojejyana, sp. nov.: F, habit; G, monocarp, adaxial view; H, petiole and twig, side view. A, D, E, from Lowry et al. 6064 (OWU); B, from Razakamalala 266 (NY); C, from Andrianjafy et al. 120 (MO); F-H, based on Miller & Randrianasolo 4423 (MO). Scale bars: A, D-G, 1 cm; B, H, 2 mm; C, 1 mm.

FIG. 29. — Distributions of Xylopia galokothamna, sp. nov., X. ghesquiereana Cavaco & Keraudren, X. humbertii Ghesq. ex Cavaco & Keraudren, X. humblotiana Baill., X. kalabenonensis D.M.Johnson, Deroin, & Callmander, X. lamii Cavaco & Keraudren, X. lastelliana Baill., X. lemurica Diels, X. lokobensis, sp. nov., X. longirostra, sp. nov., X. madagascariensis Cavaco & Keraudren, and X. marojejyana, sp. nov., on Madagascar.