Dalbergia maritima, R. Vig., Notul. Syst. (Paris)

DALBERGIA MARITIMA R.Vig., Notul. Syst. (Paris) View in CoL 14: 185 (1952), emend. Crameri, Phillipson & N. Wilding. TYPE: MADAGASCAR. Atsinanana [Toamasina]: For^ets cotieres ^de l’ Est [for^et c^otiere de Tampina], s. d. (fl), Louvel 79 (lectotype, designated by Bosser & Rabevohitra, 2002: 346): P [P00060529]!, isolectotypes (fr): P [P00060530, P00060531]!).

Deciduous tree to at least ca. 10 m tall, or shrub-like when resprouting after felling, bole to at least ca. 8 m high, DBH to at least 20 cm; bark gray-brown, becoming fissured with age. Branches glabrous ( D. maritima subsp. maritima ) or shortly villose to tomentose on young growth ( D. maritima subsp. pubescens ), brown in vivo (gray-brown to dark purple in sicco) when young, becoming gray, lenticels present. Leaves alternate, 6–10(–12) cm long ( D. maritima subsp. maritima ) or 8–13 cm long ( D. maritima subsp. pubescens ), with (8–)11–15(–18) alternate leaflets ( D. maritima subsp. maritima ) or (9–)13–21(–27) alternate leaflets ( D. maritima subsp. pubescens ), petiole and rachis yellow-green in vivo, brown to dark purple in sicco, glabrous ( D. maritima subsp. maritima ) or shortly villose to tomentose ( D. maritima subsp. pubescens ); petiole (6–) 9–12 mm long; stipules ovate, ca. 4 3 2 mm, glabrous ( D. maritima subsp. maritima ) or shortly villose to tomentose ( D. maritima subsp. pubescens ), early caducous; leaflets (7–)9–15(–19) 3 (4–)5–9(–11) mm ( D. maritima subsp. maritima ) or (7–)10–20(–23) 3 (5–)6–9(–11) mm ( D. maritima subsp. pubescens ), often noticeably smaller toward base; petiolule 1.0– 1.5 mm long, yellow-green in vivo, dark brown in sicco, glabrous ( D. maritima subsp. maritima ) or shortly villose to tomentose ( D. maritima subsp. pubescens ); lamina ovate to elliptic, coriaceous, base cuneate and often asymmetric, margins revolute in vivo and in sicco, apex obtuse, sometimes shallowly emarginate, venation brochidodromous, with 5–7 principal lateral veins per side; upper surface matt, mid-green to gray-green in vivo, red-brown to dark grayish brown in sicco, glabrous ( D. maritima subsp. maritima ) or pubescent and glabrescent ( D. maritima subsp. pubescens ), venation inconspicuous (slightly raised in sicco), midrib inconspicuous or forming a groove above; lower surface matt, paler than upper in vivo and in sicco, glabrous ( D. maritima subsp. maritima ) or pubescent especially along the midrib, becoming puberulous ( D. maritima subsp. pubescens ), venation forming a loose network of higher-order veins (often paler than matrix in sicco) below, midrib prominent. Inflorescences racemose, composed of (1–)4–12 alternate flowers each, often with imparipinnate reduced leaves subtending individual flowers especially near base (thus becoming single-flowered), 2–5 cm long; axes pale green in vivo, dark brown to dark purple in sicco, glabrous ( D. maritima subsp. maritima ) or shortly villose to tomentose ( D. maritima subsp. pubescens ); anthesis before or concurrent with leaf emergence; peduncle to 9 mm long. Flowers often subtended by glabrous ( D. maritima subsp. maritima ) or pubescent ( D. maritima subsp. pubescens ), imparipinnate reduced leaves, 12–25 mm long, with 7–13 alternate, ovate to elliptic leaflets, bracts narrowly ovate, ca. 3.0–4.0 3 1.0– 1.5 mm, early caducous; pedicel (1.5–)3–6(–7) mm long, slender, glabrous; bracteoles narrowly lanceolate, ca. 2.0 3 0.6 mm, glabrous ( D. maritima subsp. maritima ), early caducous (none seen in D. maritima subsp. pubescens ); calyx base to apex of longest petal 8–10 mm long in sicco; calyx reddish ( D. maritima subsp. maritima , fide M. Louvel) or pale yellow-green ( D. maritima subsp. pubescens ) in vivo, purple-brown, darker at base in sicco, with a 1.8–2.8 mm long tube, 4.5–6.0 mm long from base to apex of lower lobe, glabrous ( D. maritima subsp. maritima ) or with often ciliate lobe margins ( D. maritima subsp. pubescens ), persistent, 2 upper sepals long-connate, their lobes 1.2–2.0 3 1.3–1.5 mm, apex obtuse, 2 lateral sepals triangular, 1.9–2.6 3 1.0– 1.5 mm, lowest sepal triangular, margins weakly incurved, apex slightly hooked, 2.1–3.2 3 0.8–1.3 mm; petals glabrous, white at anthesis, becoming cream post anthesis, dark yellow to dark cream in sicco; standard petal elliptic to orbicular, claw and lamina forming an obtuse angle, margins incurved forwards when in full flower in vivo, base rounded, apex rounded or notched, 6.0–8.1 3 4.0–5.0 mm, including 1.6–2.6 mm long claw; wing petals 5.4–8.1 3 1.8–2.8 mm, including 1.3–1.8 mm long claw, base distinctly auriculate; keel petals 4.8–7.2 3 1.6–2.7 mm, including 1.0– 1.8 mm long claw, base distinctly auriculate; androecium glabrous, monadelphous or diadelphous, 5.8–8.4 mm long; stamens 9–10 or 9 1 1, free for upper 1.5–3.2 mm; gynoecium 4.0– 6.1 mm long, glabrous ( D. maritima subsp. maritima ) or pubescent ( D. maritima subsp. pubescens ); stipe ca. 2.0 mm long; ovary 2.4–3.0 mm long, with 3 or 4 ovules; style slender, slightly incurved, 1.6–2.4 mm long. Fruits yellow-green when immature in vivo, red-brown to purple-brown in sicco, with 1–2(–3) seeds, body oblong, 4.5–7.2 3 1.1–1.6(–1.9) cm when single-seeded, up to 8.5 3 1.9 cm when 2-seeded, base cuneate, apex rounded, surface indistinctly net-veined, glabrous; stipe ca. 8 mm long; style rarely persistent. Seeds (immature) sub-reniform, flattened, brown, ca. 11 3 6.5 mm. Figures 1A–B View FIG , 2A–B View FIG .

Notes — Dalbergia maritima was delimited by Bosser and Rabevohitra (2002) to include the populations from southeastern Madagascar recognized here as D. pseudomaritima and D. razakamalalae , as well as superficially similar collections from the northeastern part of the island (Service Forestier 2591 and 27751). However, the populations from the southeast and northeast are genetically distinct and less closely related to D. maritima than the latter is to D. louvelii s.s. (Crameri 2020), with which D. maritima co-occurs ( Fig. 3D View FIG ) and from which it is morphologically distinct, as summarized in Fig. 3A–B View FIG and Table 3 (but see notes below under D. maritima subsp. pubescens ). The narrower circumscription of D. maritima adopted here avoids confusion with the distantly related D. pseudomaritima and results in the recognition of monophyletic as well as geographically and morphologically coherent species. The binary rather than gradual differences in indument between the two infraspecific taxa of D. maritima ( Fig. 3A–B View FIG ; Table 3), along with their non-overlapping documented geographic ranges ( Fig. 3D View FIG ), align better with the rank of subspecies than variety, following the infraspecific taxonomic concepts of Christensen (1987). It would not, however, be appropriate to treat these two entities as separate species because they appear to represent one metapopulation with no genetic structure that would indicate their separate evolution, and virtually no genetic differentiation between them (F ST 5 0.01, see p. 116 in Crameri 2020).

Dalbergia maritima View in CoL was first described by R. Viguier (ined. 1944) as part of a comprehensive revision of the legumes of Madagascar, but this monumental work was destroyed at the printers in Saint-L^o during a bombardment in June 1944, and it was therefore not effectively published, according to Articles 29.1 and 32.1a of the Shenzhen Code ( Turland et al. 2018). Several years later, H. Humbert View in CoL validated the names of eleven new Dalbergia species described in Viguier’ s revision, including D. maritima View in CoL , and acknowledging R. Viguier as their posthumous author ( Viguier 1952).

Conservation Status — Dalbergia maritima View in CoL is known from 30 positively identified collection records that represent 7 extant occurrences and 5 occurrences that appear to have been extirpated. Its former extent of occurrence (EOO) was at least 2882 km 2 and its former area of occupancy (AOO) was at least 76 km 2 (based on a 4 km 2 grid), whereas its current documented geographic range has the form of an EOO of 1883 km 2 and an AOO of 56 km 2, and comprises five subpopulations. The species occurs in forest ecosystems ( Madagascar Catalogue 2021). Forest cover decline between 1953 and 2017 was estimated from the forest cover time series of Vieilledent et al. (2018a, 2018b) to be 78% in the altitudinal range of 0–450 m and within the minimum convex polygon encompassing all known collections of this species. Therefore, D. maritima View in CoL is inferred to have undergone and to be undergoing continuing decline in EOO, AOO, quality of habitat, number of subpopulations, and number of mature individuals. This species occurs at four locations with respect to the most serious plausible threat, which is selective logging for trade in its high-quality heartwood, as inferred from older collections with exploitable diameter, its documented use for carpentry, cabinet making and construction, and tree stumps observed during recent field work in east-central Madagascar. The occurrences within the protected areas of Betampona, Sahafina, and Vohibola (where a local association provides some level of protection) represent three separate locations. All occurrences outside of protected areas can be inferred to represent a single additional (fourth) location based on the IUCN Red List guidelines (IUCN 2019), because of the large spatial scale at which illegal selective logging (or habitat degradation and loss) can severely reduce the population within a single generation (at least 30–40 yr). Moreover, most known subpopulations of this species can be accessed by road or train, and harvest intensity can be regarded as similar over large spatial scales spanning similarly accessible areas. For these reasons, D. maritima View in CoL is assigned a preliminary IUCN conservation status of Endangered: EN B1ab(i,ii,iii,iv,v)12ab(i,ii,iii,iv,v).