Lepidocupania tontoutensis (Guillaumin) Buerki, Callm., Munzinger & Lowry

Buerki, Sven, Munzinger, Jérôme, Lowry Ii, Porter P. & Callmander, Martin W., 2020, Two new genera of Sapindaceae (Cupanieae) from the southern Pacific: Lepidocupania and Neoarytera, Candollea 75 (2), pp. 269-284 : 280

Lepidocupania tontoutensis (Guillaumin) Buerki, Callm., Munzinger & Lowry , comb. nov.

≡ Cupaniopsis tontoutensis Guillaumin in Mém. Mus. Natl. Hist. Nat., Sér. B, Bot. 4: 19. 1953.

Holotypus: NEW CALEDONIA. Prov. Sud: cours moyen de la Tontouta , rive droite, c. 50 m, 14.I.1945, Virot 1448 ( P [ P00639164 ]!; iso-: P [ P00639165 ]!).

= Cupaniopsis rotundifolia Adema in Leiden Bot. Ser. 15: 160. 1991.

Holotypus: NEW CALEDONIA. Prov. Sud: colline surplombant la Tontouta , 25.VIII.1984, Jaffré 2531 ( NOU [ NOU006556 ]!; iso-: P [ P00639156 , P00639158 ]!), syn. nov .

Distribution and ecology. – Lepidocupania tontoutensis is endemic to Grande Terre, where it is restricted to the Tontouta River valley. It is found in maquis vegetation on serpentine substrate, mostly alluvium, between 20 and 100 m ( ADEMA, 1991).

Notes. – Cupaniopsis tontoutensis was described based on Virot 1448. Original material at P is, however, mounted on two sheets, only one of which [ P00639164 ] bears the name of Guillaumin’s new species in his own hand, along with the word “type”. We regard this specimen as the holotype.

Cupaniopsis rotundifolia Adema was only known from the type specimen from the Tontouta River valley, with ecological and edaphic preferences similar to those of C. tontoutensis (≡ Lepidocupania tontoutensis ), as mentioned by ADEMA (1991: 161), who wrote: “Probably closely related to C. fruticosa and C. tontoutensis ”. Cupaniopsis tontoutensis was said to differ from C. rotundifolia by its fewer, wider leaflets with the secondary venation oriented at a wider angle to the midrib, and by the stiff trichomes on the endocarp of its fruits. However, several recent collections made in the lower Tontouta River valley as part of a study of rare species from this area ( D’ANGELO, 2017) show a perfect continuum in leaflet shape (as exemplified by Lannuzel & D'Angelo 49 [MPU312290], Lannuzel & D'Angelo 34 [MPU091683], and Lannuzel & D'Angelo 39 [MPU312292]) and fruits (cf. Lannuzel & D'Angelo 32 [MPU312293]), with leaves clearly corresponding to L. tontoutensis and the presence of stiff trichomes on the endocarp. We have therefore placed C. rotundifolia in synonymy under L. tontoutensis .