Xylopia richardii Boivin ex Baill.

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 : 34-35

8. Xylopia richardii Boivin ex Baill.

( Figs 1F ; 6D, F ; 8A-I )

Adansonia; Recueil d’Observations botaniques 4: 145, 146 (1864). — Xylopicrum richardii (Boiv. ex Baill.) Kuntze, Revisio generum plantarum, Pars 1: 8 (1891). — Type: La Réunion. Île Bourbon, Montagne de St. Denis , s. d. (fl., fr.), Richard s. n. [687?] (lecto-, here designated, P [ P030420 , as to Richard specimen on lower portion of sheet only]!; isolecto-, K[K001208416]!, P[P030419]!).

MATERIAL EXAMINED. — Mauritius. Macchabée [“Macabé”], 550 m, 4.II.1976 (fl.), Argent MAU 19684 (K n.v., MAU); “ Ile de France ”, without definite locality, Aublet s. n. ( BM) ; Nouvelle Découverte , high levels, 1907 (fr.), Bijoux s. n. (L[L0191349]) ; upland forests, s. d. (immature fr.), Bijoux MAU 21 ( MAU) ; without definite locality, Bijoux MAU 22 ( MAU) ; in sylvis ins. Mauritii , s. d. (fl., fr.), Bojer? s. n. (K, see below) ; without definite locality, s. d. (old fl.), MAU 18 , 19 , 20 , 3060 ( MAU) ; Crown Land Perrier , 14.II.1950 (fl., fr.), Duljeet F. D. N 055 ( MAU) ; Piton Savanne, 6.XII.1995 (st.), Florens 22735 ( MAU) ; east of Bassin Blanc , 26.I.2000 (fl., fr.), Florens et al. 24082 ( MAU) ; valley of Cascade 500 pieds, 600 m, 31.V.1975 (st.), Lorence 1274 ( MAU 17645) ; valley of Cascade 500 pieds, 600 m, 17.I.1976 (immature fr.), Lorence 1612 (K n.v., MAU 17671) ; Crown Land Macabé , 22.I.1977 (fl.), Owadally MAU 18435 ( MAU) ; without definite locality, Rivals MAU 2795 ( MAU) ; Pétrin CMA, 20°24’29.0”S, 57°28’20.0”E, 11.IV.2007 (fr.), Seepaul et al. SB013 (K) ; forest near Le Peracheret, 2100 ft, 7.II.1927 (fl.), Vaughan 434 (K).

La Réunion. Pointe de Grands Bois , VI.1905 (bud, immature fr.), d’Alleizette s. n. (L [L0191348]) ; regione St-Philippe , parte australi insulae, Mare Longue, 400-780 m, 14.I.1975 (fl., immature fr.), Bernardi 15071 (A, BM, K n.v., L [L0192019], MICH, MO, NY, P[P01954004, P01954021, P06901366], SING) ; Mare Longue , St. Philippe, II.1971 (fl.), Bosser 20651 (P[P01954005, P01954013]) ; forêt du Brulé du Baril, St. Philippe , 350 m, 19.I.1972 (fl.), Cadet 3498 (P[P01954016]) ; Mare Longue (St. Philippe), 22.II.1971 (fr.), Friedmann 1041 (P[P01954008, P01954012]) ; Marelongue (St. Philippe), 400 m, III.1973 (fr.), Friedmann 2166 (K, P[P01954027, P01954028, P01954029, P01954030]) ; Mare Longue , St. Philippe, I.1977 (fl.), Friedmann 3037 (K n.v., MAU, P[P01954010, P01954011, P01954019, P01954020, P01954023]) ; Mare Longue , 19.III.1981 (fl., fr.), Lecordier GL 6 ( MAU) ; Mare Longue forest , Réserve Biologique, alt. 150-200 m, 29.III.1973 (fr.), Lorence R 41 ( EA, K n.v., MAU 15651, MO, P[P01954006]) ; versant de la propriété de Villeneuve, Rivière de Marsonina , III.1944 (fr.), Rivals 51 (P[P01954018]) .

Provenance uncertain. “Madag.[ascar] – Côte Est, env. de Tamatave.” XI.1906 (fl. buds), d’Alleizette 111 (L[L0196007]); Herb. Du Petit-Thouars s. n. (P[P030420, upper right specimen]); Herb. Du Petit-Thouars s. n. (P[P030421]).

DISTRIBUTION, ECOLOGY AND CONSERVATION STATUS. — Xylopia richardii is endemic to the islands of Mauritius and La Réunion, where it grows in upland thickets and humid evergreen forest with a Sideroxylon species as the dominant in the canopy, at elevations of 150-780 meters ( Fig. 7 ).

LOCAL NAMES. — Bois de banane (Bernardi 15071, Bosser 20651, Cadet 3498), pigeon wood (Florens et al. 24082).Specimens with flowers and with fruits have been collected from January to March; one specimen collected in June had flower buds and immature fruits. Page (1998c) gave Xylopia richardii an IUCN conservation assessment of Vulnerable. Our EOO and AOO calculations of 558 km 2 and 36 km 2, respectively ( Table 2 ), support that assessment. The species is present in some protected areas on both islands.

DESCRIPTION Tree or shrub up to 13 m tall; d.b.h. up to 30 cm.

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

Leaves with larger blades 4.4-8.8 cm long, 2.6-3.7 cm wide, coriaceous, discolorous, grayish green to olive gray adaxially, reddish brown to orange-brown abaxially, or concolorous, elliptic, oblong, or oblanceolate, apex obtuse, rounded, emarginate, or acuminate, the acumen 2-7 mm long, base cuneate to broadly cuneate, short-decurrent on petiole, margin often revolute, glabrous on both surfaces; midrib reddened or green adaxially, secondary veins weakly brochidodromous, 9-16 per side, diverging at 55-75° from midrib, these and higher-or- der veins plane or slightly raised adaxially, slightly raised and forming a conspicuous reticulum abaxially; petiole 2.2-7 mm long, semi-terete, smooth to longitudinally wrinkled, glabrous or with a few appressed hairs.

Inflorescences axillary or from the axils of fallen leaves, 1(-2)-flowered, not pedunculate, appressed-pubescent; pedicels often recurved, 7-13 mm long, 1.8-2 mm thick; bracts 3-4, attached at or proximal to the pedicel midpoint, caducous even with smallest buds seen; buds lanceolate to linear-lanceolate, apex acute to obtuse, rarely a little falciform.

Sepals erect to spreading at anthesis, ¼-1/3-connate, 2.7- 3.8 mm long, 4.7-6.0 mm wide, coriaceous, broadly ovate, apex obtuse, appressed-pubescent abaxially.

Petals pale yellow in vivo; outer petals with position at anthesis unknown, 19-37 mm long, 5.8-7.2 mm wide at base, 3.5-5 mm wide at midpoint, fleshy, lanceolate to linear-lanceolate, flat on both surfaces, apex acute, base slightly concave, densely dusty-puberulent except for the glabrous basal concavity adaxially, densely sericeous abaxially; inner petals with position at anthesis unknown, 18-25 mm long, 3.5-4.5 mm wide at base, 1.1-1.5 mm wide at midpoint, fleshy, linear, keeled on the apical ¼ adaxially, keeled abaxially, apex acute, base deeply concave with undifferentiated margins, laterally compressed, densely dusty-puberulent except for the mostly glabrous basal concavity adaxially, densely puberulent except for glabrous base abaxially.

Stamens (150-)250-300; fertile stamens 1.4-1.7 mm long, narrowly oblong, anther connective apex 0.2-0.4 mm long, shield-shaped to capitate, overhanging anther thecae, papillate, anthers 10-13-locellate, filament 0.3-0.4 mm long; outer staminodes 1-1.5 mm long, oblong, apex truncate; inner staminodes absent; staminal cone 2.5-4.5 mm in diameter, 0.5-1.8 mm high, concealing all but the apices of the ovaries, rim even or slightly irregular.

Carpels 20-27; ovaries 1-1.5 mm long, narrowly oblong, pubescent, stigmas loosely connivent, 6.6-7.0 mm long, filiform, pilose at apices.

Fruit of up to 24 monocarps borne on a pedicel 15-22 mm long, 3-6 mm thick, glabrate or with a few scattered hairs; torus 5-19 mm in diameter, 4-9 mm high, depressed-globose; monocarps with a reddish green exterior and red endocarp in vivo, 2.5-4.8 cm long, 0.6-0.9 cm wide, 0.7-0.9 cm thick, narrowly oblong, slightly torulose, apex obtuse or with a blunt beak 1-3 mm long, base sessile or slightly contracted into a stipe 3-9 mm long, 2.5-4.1 mm thick, sometimes verrucose, longitudinally wrinkled, glabrate or sparsely pubescent; pericarp 1.1-1.4 mm thick.

Seeds up to 6 per monocarp, in a single row, oblique to long axis, 9.1-10 mm long, 5.2-6.1 mm wide, 5.1-7 mm thick, oblong-ellipsoid, flattened-elliptic to circular in cross-section, dark brown, smooth or faintly wrinkled, shiny, perichalazal ring forming a faint ridge; sarcotesta absent; aril whitish to pink in vivo, amber-colored with white flecks when dried, bilobed, lobes 2.1-3.5 mm long, 4.0- 5.9 mm wide, fleshy, smooth to wrinkled.

NOTES

Xylopia richardii differs from the other Mauritian species of Xylopia in the much smaller leaves (not exceeding 8.8 cm in length) and the smaller flowers with the outer petals lanceolate to linear-lanceolate and reaching a length of only 37 mm. There are slight differences between X. richardii specimens from Mauritius and those from La Réunion: those from Mauritius tend to have oblanceolate and emarginate leaves and shorter petals, while specimens from La Réunion have more elliptic and acuminate leaves and longer petals. There may, however, be variation in the leaf shape even on the same specimen, for example sheets of Bosser 20651 (P01954005) and Friedmann 3037 (P01954011) at P show both morphologies.

The specimen d’Alleizette 111 (L), was originally identified as Xylopia flexuosa Diels and its provenance was given as “Madag.[ascar]-Côte Est, env. de Tamatave”. It bears the leaf and bud characters of X. richardii , but this species has never been collected on Madagascar. The same collector made a collection of Xylopia richardii in June 1905 from La Réunion (see above), so it is possible that this represents a labeling error.

The original description by Baillon was based on specimens collected by Richard and Du Petit-Thouars. Richard’s specimen with the label giving the name as “ Xylopia richardi Bvn.” is designated here as the lectotype. The lectotype specimen is mounted on the same sheet as a collection of X. richardii with fruits from the Herb. Du Petit-Thouars. A second collection by Richard, identical in the size and shape of the leaves and the degree of maturation of flowers and fruits, is considered to be an isolectotype; a label on the sheet gives the name as “ Xylopia richardiana H. Bn. ” and the specimen is identified as having been a part of the Drake Herbarium, which was acquired by P in 1913 ( Stafleu & Cowan 1976). A second specimen from the Herb. Du Petit-Thouars (P030421) that has only flowers and leaves with more acute apices than on any of the other specimens, was specifically mentioned by Baillon in the protologue: “ Stirpis hujusce formam alteram ss, foliis apice angustioribus elongatis acuminatis, dignitati specificae, ut mihi videtur, non sat aequalem, in herbario Thouarsiano nuperrime detexi ”.

Figures

FIG. 1. — Aspects of Xylopia L. vegetative and floral morphology: A, shrub habit of X. humblotiana Baill.; B, habit of X. bemarivensis Diels, showing several nodes with both collateral buds forming shoots, creating pseudo-opposite branches; C, flowers of X. lastelliana Baill., showing inner petals bent outward through the gaps between outer petals (Schatz & Modeste 2877); D, flowers of X.perrieri Diels showing conspicuous red coloration at the bases of the outer petals (Schatz & O’Connor 2964); E, spreading outer petals and erect inner petals of X. kalabenonensis D.M.Johnson, Deroin, & Callmander (Razafitsalama et al. 1041); F, flower of X. richardii Boivin ex Baill., with stigmas emerging in the center amidst the inner petals; G, inflorescences of X. beananensis Cavaco & Keraudren, showing a bud, two flowers with petals, stamens, and stigmas fallen so that the staminal cone is visible, and one open flower (Buerki 14); H, open flower of X. lamarckii Baill.; I, open flower of X. lamarckii with one outer petal and one inner petal removed to show interior of flower, including stamens and stigmas. Photos: A, M. C. Andriamahay; B, F. Rakotoarison; C, D, G. E. Schatz; E, J. Razafitsalama; F, H, I, C. Kaiser-Bunbury; G, M. W. Callmander. A, B, used under the terms of the Creative Commons license for iNaturalist; C-E, G, used under the terms of the Creative Commons license for Tropicos, the botanical information system at the Missouri Botanical Garden.

FIG. 6. — A, Shoot of X. amplexicaulis (Lam.) Baill., showing flower bud at left and clasping leaf bases visible at several nodes; B, branch of X. ravelonarivoi, sp. nov., with fruit (Ravelonarivo 4171); C, flower of X. humblotiana Baill., side view (Schatz 4475); D, buds of X. richardii Boivin ex Baill.; E, close-up of flower interior of X. lamarckii Baill., showing red coloration at bases of petals, and the stamens and stigmas; outer staminodes are visible along the edge of the androecium; F, flower of X. richardii at anthesis, one outer petal and one inner petal removed, so that androecium and stigmas are visible; G, leaves and fruit of X. anomala, sp. nov., (Rakotonirina 48); H, leaves and fruit of X. sericolampra Diels. Photos: A, Carlos Magdalena; B, D. Ravelonarivo; C, G. E. Schatz; D-F, C. Kaiser-Bunbury; G, C. Birkinshaw; H, R. N. Rabarijaona. B, C, G, used under the terms of the Creative Commons license for Tropicos, the botanical information system at the Missouri Botanical Garden; H, used under the terms of the the Creative Commons license for iNaturalist.

FIG. 8. — Xylopia richardii Boivin ex Baill., X. beananensis Cavaco & Keraudren, and X. flexuosa Diels. A-I, X. richardii: A, stamen, abaxial view; B, flower bud, side view; C, D, leaves; E, fruit; F, seed, view of micropylar end; G, seed, side view; H, basal half of inner petal, adaxial surface; I, outer petal, adaxial surface. J-P, X. beananensis: J, outer petal, adaxial surface; K, inner petal, adaxial surface; L, flower bud, side view; M, seed, view of micropylar end; N, seed, side view; O, leaves; P, fruit. Q-X, X. flexuosa: Q, inner petal, adaxial surface; R, outer petal, adaxial surface; S, stamen, abaxial view; T, seed, view of micropylar end; U, seed, side view; V, fruit; W, leaf; X, flowers, side view. A, C, H, I, from Friedmann 3037 (MAU); B, from Florens et al. 24082 (MAU);D, from Bernardi 15071 (NY); E-G, from Lorence R 41 (MO); J-L, from isotype specimen at TAN; M, N, P, from Ravelonarivo & Rabesonina 569 (OWU); O, from Dorr 3588 (NY); Q-S, from Perrier de la Bâthie 4973 (B); T-V, from Service des Eaux et Forêts de Madagascar 12450 SF (P); W, X, from Decary 5570 (P). Scale bars: A, S, 1 mm; B, L, X, 1 cm; C-E, O, P, V, W, 2 cm; F, G, M, N, T, U, 3 mm; H-K, Q, R, 5 mm.

FIG. 7. — Distributions of Xylopia amplexicaulis (Lam.) Baill., X. lamarckii Baill., and X. richardii Boivin ex Baill. on the islands of La Réunion and Mauritius.