Chassalia psychotriformis I.M.Turner, 2021

Yu, Tian Yi, Turner, Ian M. & Cheek, Martin, 2021, Revision of Chassalia (Rubiaceae-Rubioideae-Palicoureeae) in Borneo, with 14 new species, European Journal of Taxonomy 738, pp. 1-60 : 52-53

Chassalia psychotriformis I.M.Turner nom. nov.

Replaced synonym:

Cephaelis psychotrioides Valeton, Icones Bogorienses 4 (3): t. 357 ( Valeton 1913b). – Chassalia psychotrioides (Valeton) I.M.Turner, Feddes Repertorium 139: 399 ( Turner 2019), nom. illegit., non Chassalia psychotrioides DC. , Prodromus Systematis Naturalis Regni Vegetabilis 4: 531 (1830) ( Candolle 1830). – Type: INDONESIA • Borneo, Liang Gagang ; 1893–1894; Hallier 2703; hololectotype:BO[BO-1374040], designated by Turner (2019: 399); isolectotype: BO[BO-1374039].

Additional material

MALAYSIA – Borneo, Sarawak • Serian, Gunong Penrissen; 2 May 1962; Ilias Paie S 16336 ; K!, L, SAR • Serian, Tebedu, Bukit Simurus ; 12 Feb. 1985; Abg. Mohtar S 49281 ; K!, SAR • 2 nd Division, Lubok Antu District, Lanjak-Entimau P. F., Sg. Jelok, near Bukit engkajang; 18 Mar. 1974; Paul Chai S 34024 ; K!, L, KEP, MO, SAN, SAR •

INDONESIA • Borneo, Jaro Dsm, 10 km NE of Muara Uya , Kalimantan Selatan; alt. 90 m; 16 Nov. 1971; Kuswata Kartawinata 828; K!, L .

Description

Shrub to small tree, 1–1.5 m tall. Stem terete, central part slightly canaliculate when dry, hairy from the first or second internode from apex. Internodes 1.5–8 cm × 4 mm. Leaf-blades obovate to elliptic, 20.5–28.5 × 5.5–8 cm, apex acute to acuminate, base truncate, adaxial surface glabrous, abaxial surface hairy, midrib slightly raised on both sides, densely hairy abaxially, petiole 2–5.5 cm long, young petiole hairy, glabrescent. Stipule flabellate, apex usually broken, 3–8 × 5–10 mm, slightly hairy when young. Inflorescence a compound cyme, 7 cm long, all parts hairy except fruits; peduncle 4 cm long, bracts of peduncle stipule-like, 1 × 5 mm, first branches and first internode of rachis 2–2.5 cm long, bracts of first branches and first internode of rachis 2, 4–6 × 1–2 mm, second branches and second internode of rachis 3.1 cm long, bracts of second branches and second internode of rachis 2, slightly smaller than bract of first branches and first internode of rachis, 2 × 2 mm, bracts of capitulum 2–3 × 2 mm. Flowers not seen. Fruits 8–10 × 4–9 × 4–6 mm, blackish brown when dry, calyx persistent, not accrescent, 0.4 × 2 mm, disc persistent, not accrescent, 0.5 × 1 mm. Pyrenes plano-convex, 8–9 × 4–9 × 4–6 mm, dorsal surface convex, with two adjacent parallel longitudinal crests, 0.5 mm wide, 0.25 mm apart along their length, forming a longitudinal groove from apex to base between the two crests; ventral surface concave, central part slightly elevated, margin with an endocarpal outgrowth 1–1.2 mm wide, with a groove between the edge of endocarp and endocarpal outgrowth 0.5 mm wide. Raphal opening, bony spine, PGS, seed and endosperm not detected.

Distribution

Borneo: West Kalimantan, Bukit Liang; Sarawak, First Division, Serian, Gunung Penrissen.

Remarks

Turner (2019) transferred Cephaelis psychotrioides Valeton to Chassalia . The resultant new combination was illegitimate, being a later homonym of Chassalia psychotrioides DC. , a species from Mauritius. Therefore a nomen novum is here published for Valeton’s name for the Bornean species.

Valeton’s type specimen Hallier 2703 (BO-1374040) has a hairy infructescence. Additional information provided by the drawing included in the original publication of this species also shows that it has hairy petioles and abaxial leaf midribs ( Valeton 1913b). The species differs from other Asian species of Chassalia by having a hairy petiole, lower midrib and secondary nerves of the leaves, also the stem apices and inflorescences are densely pubescent.

Chassalia psychotriformis is restricted to a region straddling the Sarawak-Kalimantan border in Borneo based on specimen records from K and other herbaria. The most distinctive vegetative character of C. psychotriformis is the pubescent abaxial surface of the leaves and the pubescent peduncles. It is the only species that has been found with a hairy peduncle among all Asian species of Chassalia . Therefore, the identification of C. psychotriformis is not difficult compared to that of most other Bornean species of Chassalia .