Xylopia galokothamna 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 : 60-62

publication ID	https://doi.org/ 10.5252/adansonia2020v42a1
DOI	https://doi.org/10.5281/zenodo.3883306
persistent identifier	https://treatment.plazi.org/id/417D87A4-FFC0-FFD3-FC03-500036E1FB33
treatment provided by	Tatiana
scientific name	Xylopia galokothamna D.M.Johnson & N.A.Murray
status

Treatment

21. Xylopia galokothamna D.M.Johnson & N.A.Murray , sp. nov. ( Figs 16C, D View FIG ; 23F-L, N View FIG )

Xylopia species belonging to the Madagascar group with relatively broad outer petals and clavate stigmas, but distinguishable from the other species of the group by the shrub habit, cuneate to broadly cuneate leaf bases, stamens 1.5-2.0 mm long borne on a staminal cone c. 1.8 mm high, monocarps with a beak 1.5-3 mm long and stipe 4-5 mm long and 2.8-4.8 mm thick, and ovoid seeds 11.8-13.3 mm wide.

TYPE. — Madagascar. Prov. Antsiranana, Diana Region, Ambilobe , Beramanja , Anketrabe , forêt de Kalabenono , Ambatoharanana , 13°38’46”S, 48°40’30”E, 706 m, 24.XI.2006 (fl., fr.), Callmander et al. 585 (holo-, P [ P01986966 ]!; GoogleMaps iso-, MO!, OWU!).

PARATYPE. — Madagascar. Prov. Antsiranana, Diana Region , Ambilobe , Beramanja , Ambatoharanana , Anketrabe belinta , Kalobinono Manongarivo , 5 km au sud de Belinta, 13°38’40”S, 48°40’26”E, 700 m, 28.IX.2013 (fr.), Ratovoson 2065 ( MO, P [ P01044912 ]). GoogleMaps

DISTRIBUTION, ECOLOGY AND CONSERVATION STATUS. — Like X. kalabenonensis , this is a new species revealed by recent collecting efforts in the Galoka Mountain chain of northwestern Madagascar ( Callmander et al. 2009). Xylopia galokothamna , sp. nov., is known from a single locality in humid forest at c. 700 m elevation ( Fig. 29 View FIG ). The specimen with flowers was collected in November, the specimens with fruits in September and November. The small EOO and AOO values, 5 km 2 and 8 km 2, respectively, lead to a preliminary conservation assessment of Endangered ( Table 2 View TABLE ).

DESCRIPTION Shrub up to 6 m tall.

Twigs sparsely appressed-pubescent, the hairs 0.1-0.3 mm long, soon glabrate; nodes with one axillary branch.

Leaves with larger blades 10.4-14.0 cm long, 3.7-5.0 cm wide, subcoriaceous, concolorous or slightly discolorous and brownish green adaxially, reddish brown abaxially, elliptic to oblong-elliptic, apex acuminate, the acumen 5-9 mm long, base cuneate to broadly cuneate, decurrent on petiole, margin flat or slightly recurved, glabrous but densely verrucose adaxially, sparsely appressed-pubescent and soon glabrate abaxially; midrib darkened toward base adaxially, secondary veins brochidodromous, 15-18 per side, diverging at 60-90° from midrib, these and higher-order veins slightly raised or indistinct adaxially, raised and distinct abaxially; petiole 4-8 mm long, canaliculate, wrinkled, sparsely pubescent to glabrate.

Inflorescences axillary, 1-flowered, not pedunculate, densely pubescent; pedicels 2.0- 4.5 mm long, 1.6-2.0 mm thick;

bracts not seen; buds linear-lanceolate, apex acute, slightly falciform ( Fig. 16C View FIG ).

Sepals spreading at anthesis, c. 1/3-connate, 2.3-3.5 mm long, 3.8-4.5 mm wide, coriaceous, broadly triangular, apex acute, densely pubescent abaxially.

Petals yellow in vivo; outer petals slightly spreading at anthesis, c. 18 mm long, 4.4-5.9 mm wide at base, 2.7- 3.0 mm wide at midpoint, slightly fleshy, linear-lanceolate, keeled on apical ¼ but otherwise flat adaxially, weakly keeled abaxially, apex obtuse, densely puberulent except for the glabrous base adaxially, densely appressed-pubescent abaxially; inner petals with apices spreading at anthesis, 11.4-12.8 mm long, 3.3-3.5 mm wide at base, c. 1.3 mm wide at midpoint, slightly fleshy, linear-lanceolate, keeled on apical 1/2 adaxially, keeled abaxially, apex acute, base concave with undifferentiated margin, densely puberulent except for glabrous base on both surfaces, with a band of papillae across widest point adaxially.

Stamens c. 170; fertile stamens 1.5-2.0 mm long, narrowly oblong, anther connective apex 0.3-0.4 mm long, capitate to slightly conical, overhanging anther thecae, papillate, anthers 12-14-locellate, filament 0.5-0.7 mm long; outer staminodes 1.6-2.6 mm long, clavate or narrowly oblong, apex obtuse; inner staminodes 1.1-1.4 mm long, oblong, apex rounded; staminal cone c. 2.4 mm in diameter, c. 1.8 mm high, concealing all but the apices of the ovaries, rim irregularly laciniate.

Carpels 5-7; ovaries <2 mm long, oblong, pubescent, stigmas connivent, 2.8-3.2 mm long, narrowly clavate, with a few hairs.

Fruit of up to 3 monocarps borne on a pedicel 5-8 mm long, 3-3.7 mm thick, sparsely pubescent; torus 5-6 mm in diameter, 4.5-5 mm high, ovoid; monocarps with yellow exterior in vivo, 2.9-5.1 cm long, 2.0- 2.8 cm wide, (0.7-) 1.4-2.4 cm thick, oblong or ovoid, not torulose to slightly torulose, apex rounded to a broad beak 1.5-3 mm long, base contracted into a stipe 4-5 mm long, 2.8-4.8 mm thick, verrucose, obliquely wrinkled and with a narrow ridge encircling the monocarp lengthwise, dull, finely pubescent; pericarp 1.0-2.0 mm thick.

Seeds up to 5 per monocarp, in a single row, oblique to perpendicular to long axis, 14.1-16.2 mm long, 11.8-13.3 mm wide, 8.6-11.2 mm thick, ovoid, sometimes slightly flattened, broadly elliptic to semicircular in cross-section, light yellowbrown, smooth, dull, perichalazal ring visible as a flat darkened band; presence of sarcotesta not determinable; aril absent.

NOTES

Xylopia galokothamna , sp. nov., is one of the few Madagascar Xylopia species with a shrub habit. It is part of the species group with clavate stigmas and often relatively broad petals, and within that group stands out by the combination of short thick flower pedicels, distinct beak and stipe on the fruits, and the broad seeds. It occurs in the same gen- eral region of Madagascar as X. lokobensis , sp. nov., but leaf shape, pedicel length, and habit distinguish the two species. The type specimen was one of several identified as “ Xylopia sp. aff. fananehanensis ” in Stull et al. (2017) that are recognized in this work as distinct species.

The type and paratype collections have monocarps that are finely pubescent, with a pericarp 1-2 mm thick. Three additional specimens collected from the same general area of the Galoka Mountains have in common the shrub habit, relatively large seeds, and a broad beak and stipe of the monocarps: Buerki et al. 20 (MO), Diana Region, Chaîne Galoka, Mont Galoka, Anketrabe-Belinta, Ambilobe, Beramanja, Camp Bilahy, 13°35’20”S, 48°43’42”E, 928 m, 23.II.2005 (fr.); Callmander et al. 720 (MO), Ambanja, commune Beramanja, 13°38’40”S, 48°40’09”E, 518 m, 22.XI.2007 (fr.); Rakotovao et al. 3823 (MO). Ambilobe, Beramanja, Anketrabe, village le plus proche Antanambao Belinta, 1007 m, 13°39’10”S, 48°40’29”E, 28.XI.2007 (fr.). All of these specimens, however, have monocarps that are glabrous, more elongate (up to 7 cm long), and strongly torulose ( Figs 16E View FIG , 23M View FIG ), with the pericarp only 0.2-0.7 mm thick; the labels of all three specimens indicate that the monocarps are tinged with red and the label of Buerki 20 describes the seeds as orange. The leaves of these specimens are more lanceolate, glabrous to glabrate, and lack the verrucose adaxial surface. Given the degree of disparity in the fruit, and to a lesser extent the vegetative features, we exclude these specimens as paratypes of X. galokothamna , sp. nov., but draw attention to the similarities and the fact that additional collections are needed to resolve their status.