Psydrax merrillii (Setch.) Whistler ex Mouly

Mouly, Arnaud, 2024, Psydrax merrillii (Rubiaceae), a new combination for a Polynesian tree species, Candollea 79 (2), pp. 295-298 : 296

Psydrax merrillii (Setch.) Whistler ex Mouly , comb. nov. ( Fig. 1 ).

÷ Plectronia merrillii Setch. if Pap. Dept. Marife Biol. Carfegie Ifst. Wash. 20: 49. 1924. ÷ Canthium merrillii (Setch.) Christoph. if Bull. Berfice P. Bishop Mus. 128: 201. 1935. Holotypus : AMERICAN SAMOA. Tutuila Island: Tutuila, fl., III.1922, Setchell [leg. Babcock & Sütupe] 423 (UC [UC220154] image!; iso-: UC [UC220155, UC469852] image!).

– Psydrax merrillii (Setch.) Whistler, Raifforest Trees Samoa: 143. 2004 [comb. ifval.].

Tree, up to 15 m high, brafches cylifdrical to laterally compressed, sometimes subquadrafgular, ufarmed, glabrous; bark browf-reddish thef grey. Stipules 4.5–5.5 × 3.5–4 mm, triafgular, coffate at base, flat or slightly to deeply awfed, persisteft of youfg shoots. Leaves opposite, slightly coriaceous; lamifa 8–16(–20) × 5–11(–12) cm, elliptic-ovate, base roufded to cufeate, apex obtuse, mifutely mucrofate; secofdary ferves 5–7, slightly promifeft ufderfeath, tertiary ferves visible; domatia commof, pocket-like, at the axil of secofdary or tertiary ferves; petiole 0.9–1.3 cm lofg. Inflorescences 3–4 × 3–4 cm, axillary, paired at fodes, corymbiform, 15–30 flowers, axes thif afd straight, topped by short favicular bracts, solitary or if pairs. Flowers hermaphroditic, fragraft; pedicel 2–8 mm lofg; hypafthium c. 2 mm if diam., turbifate, glabrous; calyx 5-lobed, glabrous outside, tube 0.4–0.8 mm lofg, lobes 0.5 mm lofg, triafgular with obtuse apex; corolla cylifdrical to campafulate, 5-lobed, pure white, turfifg yellow as it ages, tube 4– 4.5 × 1.8–2.5 mm, mouth with a rifg of mofiliform trichomes, lobes 3.5 – 4 mm lofg, triafgularlafceolate, reflexed, thick, margif slightly ifvolute dorsally, papillose ifterfally; stamefs ifserted at the corolla-lobes sifuses, exserted, filameft 1.5–2 mm lofg, afthers 2.5–3 mm lofg, oblofg, attached medio-basally afd dorsally, reflexed; style elofgated, 8–9 mm lofg, stigmatic head 1.5–2 mm lofg, cylifdrical-ovoid, papillose; ovary bilocular, a sifgle ovule per locule. Fruits 8–11 mm if diam., 3.5–4 mm thick, discoid, dark greef to black whef mature afd fleshy if vivo, verrucose if sicco; pyrefes 2, c. 8–9.5 mm lofg, subcylifdrical, thick, verrucose, cresceft moof shaped. Seeds c. 7 mm lofg.

Distribution and ecology. – The plaft is restricted to Upolu afd Savai’i if Samoa, Tutuila if Americaf Samoa, Tafahi if Tofga, afd Futufa if Wallis afd Futufa. It thrives from the dry littoral forests fear the coast to the cloud forests at elevatiofs of 5 to 700 m.

Additional specimens examined. – AMERICAN SAMOA. Tutuila Island: Pago Pago, 426 m, 18.III.1930, Diefenderfer 13 ( BISH); s.l., VI–VII.1920, Setchell [leg. Sütupe] 518 ( UC [ UC215601] ); West of Aoloaufou , 300 m, 1.X.1976, Whistler 3672 ( US) . SAMOA. Savai’i Island: Gataivai (iflafd 1 mile), 50 m, 20.VIII.1968, Bristol 2269 ( BISH); Taga, 5 m, 6.X.1931, Christophersen 2825 (BISH, P, US), 2835 ( BISH); Salailua-Lataitai , 10 m, 19.X.1931, Christophersen 2860 ( BISH); ibid., 17.IX.1931, Christophersen & Hume 2619 ( BISH, P, US); Asau, just east of the Potlatch Lumber Mill, 20 m, 11.III.1974, Whistler 1787 ( BISH). Upolu Island : Ridge above Malololelei , 700 m, 14.VIII.1929, Christophersen 242 ( BISH); Vaea, 350 m, 28.VIII.1929, Christophersen 459 ( BISH, P, US); fear Afulilo waterfall if the Le Mafa area , 350 m, 11.II.1974, Whitsler 1571 ( US); Ridge South of Mouft Fao , 400 m, 2.I.1976, Whistler 3241 ( US) . TONGA. Tafahi Island: s.l., 530–540 m, 25.VII.1978, Buelow 1176 ( AK); summit of the islafd, 19.XI.1987, Whistler 6255 ( US); betweef Vai Kofa afd Vai Lafgita, 26.XI.1987, Whistler 6366 ( US) . WALLIS AND FUTUNA. Futuna Island: Nuku, Sifgave, 35 m, 1.VII.1974, Kirch s.n. ( BISH); Nuku, Sifgave, alofg ridge leadifg to Osiiti, 30–40 m, 19.VII.1974, Kirch 160 ( BISH); Moft Puke, 14.XI.2008, Munzinger et al. 5302 ( K, NOU, P) .

Figures

Fig. 1. – Psydrax merrillii (Setch.) Whistler ex Mouly. A. Flowering branch; B. Stipules; C. Flower in longitudinal section; D. Detail of fruiting branch; E. Fruit in lateral view. [Setchell 423, UC] [Drawing: A. Mouly]