Decalobanthus bracteatus (P.S.Bacon) A.R.Simões & Staples

4. Decalobanthus bracteatus (P.S.Bacon) A.R.Simões & Staples View in CoL — Map 3 View Map 3

Decalobanthus bracteatus (P.S.Bacon) A.R. Simões & Staples (2017) View in CoL 569. — Merremia bracteata P.S. Bacon (1982) View in CoL 259. — Type: Bacon 2 (holo K [K000830896];iso BSIP n.v., L [L 0363556]), Solomon Islands, Kolombangara, near Poitete forestry camp.

Stems and branches lenticellate. Leaves basally attached, ovate, up to 24 by 20 cm, bases cordate; secondary veins 8–10 on either side of the midvein. Inflorescences racemes or simple panicles; peduncles up to 21 cm long; bracts elliptic, c. 3 by 2 cm, apex obtuse, apiculate, persistent. Flowers: sepals subequal, ovate, to 3 by 1.25 cm; corollas broadly funnelform-campanulate, lemon-yellow, c. 5 cm long, outside golden gland-dotted; stamens included, anthers 5–6 mm long, spirally twisted; pistils included. Fruiting calyx persistent and accrescent, loosely cupping fruit; sepals c. 3 by 2.6 cm. Fruits seemingly indehiscent, depressed globose, c. 1.2 cm tall by 2.6 cm diam. Seeds 2.

Previously published illustration — Bacon (1982: 262, f. 3).

Distribution — Solomon Islands (Kolombangara, Vanikoro, Vella la Vella).

The recent report ( Simões et al. 2020) that Decalobanthus ranges as far across the Pacific as ‘Santa Cruz Island, North America’ is a very unfortunate failure to distinguish Santa Cruz in the California Channel Islands from the Santa Cruz group in the Solomon Islands. So far as currently known D. bracteatus is endemic to the Solomon Islands and does not occur off the coast of North America.

Habitat & Ecology — At forest margins, in secondary forest regrowth and forestry plantations; soil volcanic basaltic clay. Elevation sea level to 115 m.

Vernacular name — Ambui (Kwara’ae; Bacon PB­2).

Notes — The fruits of D. bracteatus are imperfectly known: the holotype sheet in Kew has a single fruit enclosed in the fragment capsule. From what can be discerned in a digital image, the fruit appears to be the blackish, indehiscent type similar to those of D. borneensis and D. pulcher .

Only four specimens of D. bracteatus have been studied; this gives the impression that the species is rare. However, the Solomon Islands have not been well botanized and the herbarium collections in BSIP and SUVA have been unavailable for study for decades. It is quite possible that D. bracteatus is more common than the few collections available would suggest.