Christiana vescoana (Baill.) Kubitzki

6. Christiana vescoana (Baill.) Kubitzki View in CoL , Bot. Jahrb. Syst. 116 (4): 541. 1995.

Berrya vescoana Baill. , Adansonia 10: 240. 1872. Type. Tahiti. Sine loc., 1847 (fr), J. N. E. Vesco s. n. (lectotype, here designated: P [P 00637093; digital image!]; isolectotypes: BISH [ BISH 1003216; digital image!], P [P 00637094; digital image!], P [P 00637095; digital image!], P [P 04756685; digital image!], P [P 04756686; digital image!]).

Entelea tahitensis Nadeaud View in CoL , Énum. Pl. Tahiti 69. 1873. Type. Tahiti, [Ravins de Papaihonu, 600 m.], s. d. (fr), J. Nadeaud 439 (lectotype, here designated: P [P 04756684; digital image!]; isolectotypes: BISH [ BISH 1003217; digital image!], G, 3 sheets [G 00393886; digital images!], P [P 04756683; digital image!], P [P 00637089; digital image!], P [P 00637090; digital image!], P [P 00637091; digital image!], P [P 00637092; digital image!]).

Berrya tahitensis (Nadeaud) Drake View in CoL , Ill. Fl. Ins. Pacif.: 125. 1890 [“ 1886 ”] (“ B. (?) Tahitensis View in CoL ”). Type. Based on Entelea tahitensis View in CoL .

Tahitia vescoana (Baill.) Burret View in CoL , Notizbl. Bot. Gart. Berlin-Dahlem 9: 607, 610. 1926. Type. Based on Berrya vescoana .

Tahitia tahitensis (Nadeaud) S. L. Welsh View in CoL , Fl. Societensis: 282. 1998. Type. Based on Entelea tahitensis View in CoL .

Type.

Based on Berrya vescoana Baill.

Description.

Trees, 5–8 m tall. Leaves: petioles 2.5–6.5 cm long, leaf blades 11–21 × 7.3–11 cm, widely ovate, concolorous to slightly discolorous, bases cordate, margins slightly dentate apically, apices acuminate, stellate trichomes above and below. Inflorescences short peduncled; flowers attached to peduncle. Capsules syncarpous, c. 1 cm long, depressed-globose, wings conspicuous.

Distribution and habitat.

Found only on the islands of Moorea and Tahiti in French Polynesia at 100–280 (– 600) m elevation. The species is poorly known with relatively few recent collections.

Phenology.

Fruiting specimens collected in April, May, and June.

Conservation status.

Christiana vescoana has a restricted and endemic population and presents an AOO of 20 km 2 and EOO of 248.140 km 2. It is assessed here as Critically Endangered (EN), under D 1 criterion as it has a reduced number of mature individuals, according to IUCN (2012).

Vernacular names.

Unknown.

Etymology.

The specific epithet honors Jean Nicolas Eugène Vesco, Naval surgeon and botanist, who collected the type.

Additional specimens examined.

French Polynesia. Moorea: Vallée de Maharepa, 23 Apr 2004 (fr), J. F. Butaud 439 (P, 2 sheets [P 05253217, P 05253221; digital images]); Mt Raaiu [sic], 16 Apr 1898 (fr), J. Nadeaud s. n. (P [P 05253216; digital image]). Tahiti: Vallée du Panaruu, 21 May 1896 (fr), J. Nadeaud s. n. (P, 3 sheets [P 05253218, P 05253219, P 05253220; digital images]); Sine loc., 1870 (fr), M. Pancher s. n. (P [P 05253224; digital image]); Vallée de Faataua, 09 May 2005 (st), W. Teamotuaitau 26 (P [P 05253226; digital image]); Punaruu, 02 Jun 2005 (fr), W. Teamotuaitau 35 (P [P 05253222; digital image]). Sine loc., sine coll. (P [P 05253225; digital image]); Sine loc., 1855 (fr), M. Vieillard & M. Pancher s. n. (P [P 05253227; digital image]).

Discussion.

Christiana vescoana shares dentate leaf margins with C. macrodon , but it is distinguished by characters previously mentioned (and also given in the key).

For additional details see Florence (2004).

The description of Berrya vescoana was based on an unnumbered collection made by M. Vesco in Tahiti: this collection, including duplicates, is now housed in the herbarium in Paris (P). Kubitzki (1995) noted the type was in P, but only wrote “ Vesco a. 1847 (P) ” where “ 1847 ” refers to the year of collection, not a collection number. Five duplicates of this unnumbered collection are found now in P, none of them have the “ a ” noted by Kubitzki, and consequently, we designate the most complete specimen with fruits and seeds (P barcode P 00637093) here as the lectotype. It is also the same specimen that Florence (2004) considered to be the “ holotype. ”

When Nadeaud (1873) described Entelea tahitensis he associated it with a single collection (Nadeaud 479) for which he also indicated there were duplicates (“ un nouvel examination de mes échantillons … ”). There therefore is no holotype as indicated by Florence (2004) who stated that one was deposited in G. Additionally, Florence’s statement cannot be interpreted as designating a lectotype since it contravenes the rules of the ICN ( Turland et al. 2018; Arts. 7.3, 9.23). Here, we designate as lectotype the only specimen in P (P barcode P 04756684) with fruits.