Timonius flavescens ( Jack 1823: 127 ) Baker (1877: 144)

Chen, Junhao & Wong, Khoon Meng, 2020, Typification and nomenclatural notes on Bornean Timonius (Rubiaceae: Guettardeae), Phytotaxa 446 (2), pp. 114-120 : 116

Timonius flavescens ( Jack 1823: 127) Baker (1877: 144)

Basionym: Helospora flavescens Jack

Lectotype: —[Published illustration] (♀) Jack (1823: 130, t. 4, fig. 3), designated in Wong et al. (2019).

Epitype: — INDONESIA. Sumatra, Palembang, Ogan Oeloe, sin. dat. (♀), Teijsmann HB3877 (epitype U [U.1577430], designated in Wong et al. (2019)).

= Guettarda brunonis Wall. ex G. Don (1834: 552) , syn. nov.

Type:— SINGAPORE. Sin. loc., 1822 (♀), Wallich s.n. [EIC 6220] (holotype K-W [K001123335]).

= Bobea sericantha f. glabrior Miquel (1861: 545)

Type:— INDONESIA. Sumatra, Palembang, Ogan Oeloe, sin. dat. (♀), Teijsmann HB3877 (holotype U [U.1577430]).

= Timonius flavescens var. brevipetiolata Valeton (1909a: 35)

Type:—BORNEO. Bukit Singkadjang, 1905 (♀), Teijsmann 8348 (lectotype BO [acc 1435253], designated here; isolectotypes BO [acc 1570710; acc 1570711; acc 1570712]).

= Timonius peduncularis (Wall. ex G. Don 1834: 551) Ridley (1923: 113)

Basionym: Guettarda peduncularis Wall. ex G.Don

Type :— SINGAPORE. Sin. loc., 1822 (♀), Wallich s.n. [EIC 6222] (lectotype K-W [K000763583], first step designated in Wong et al. (2019), second step designated here to include only four detached leaves (see notes); isolectotype K-W [K001123337], explicitly excluding the left element which represents another gathering) .

Notes: —Although originally described from Sumatra, T. flavescens has been recorded in Borneo ( Merrill 1921a, Masamune 1942, Sidiyasa et al. 1999). Jack cited no specimen for Helospora flavescens , merely stating “Native of Sumatra”, so it has to be assumed that his taxon is based on a collection by himself from Sumatra, which has not been found. Baker’s description of the plant in the Seychelles was brief, but had effectively recombined Jack’s name because he cited Jack’s binomial under his T. flavescens . Baker cited collections by Pervillé, Wright and Horne from the Seychelles, which have been subsequently recognised as a separate species, T. sechellensis Summerhayes (1928: 391) ; it is different from T. flavescens because of its much shorter (less than 1 cm long) pistillate and fruiting peduncles. Teijsmann HB3877 is one of the specimens identified as T. flavescens in an early taxonomic treatment of Timonius ( Valeton 1909a) ; because this specimen is from Sumatra, it was selected as the lectotype of T. flavescens by Wong (1988). Darwin (1997) designated the same Sumatran specimen as the neotype of T. flavescens , correcting Wong’s earlier use of the term lectotype, given that this specimen is not part of the original material cited in Jack’s protologue. Both authors overlooked the presence of a published illustration in the protologue, however. Wong et al. (2019) therefore selected the published illustration as lectotype and designated the Sumatran specimen as epitype because the illustration is inadequate for identification purposes.

Timonius flavescens var. brevipetiolata Valeton was described based on two of Teijsmann’s collections, but only one of them (Teijsmann 8348) can be located and has a collection number. One of the duplicates in BO [acc 1435253] is the best preserved and is therefore here designated as lectotype. Timonius flavescens var. grandiflora Valeton (1909a: 35) is excluded from the definition of this species here.

The type material of T. peduncularis (Wallich s.n. [EIC 6222]) is represented by two sheets in K-W, both with mixed elements of T. finlaysonianus (Wall. ex G. Don 1834: 552) Hook.f. (1880: 127) and T. flavescens . The sheet [K000763583] designated as lectotype by Wong et al. (2019) comprises largely elements of T. finlaysonianus , with only four detached leaves of T. flavescens (marked with ‘X’ in pencil) mounted together with an intact twig of T. finlaysonianus . The other sheet [K001123337] that is not cited in Wong et al. (2019) has three separate branches: two intact twigs of T. flavescens with several attached fruits (middle and right) and one intact twig of T. finlaysonianus (left). According to Art. 9.14 of the International Code of Nomenclature for algae, fungi, and plants ( Turland et al. 2018), when a type consists of elements belonging to more than one taxon, “the name must remain attached to the part that corresponds most nearly with the original description or diagnosis”. Therefore, we here designate K000763583 (explicitly including only four detached leaves of T. flavescens ) as second-step lectotype. We also here designate K001123337 (excluding the left element) as isolectotype of T. peduncularis .