Christiana eburnea (Sprague) Kubitzki

2. Christiana eburnea (Sprague) Kubitzki View in CoL , Bot. Jahrb. Syst. 116 (4): 541. 1995.

Fig. 2 View Figure 2

Asterophorum eburneum Sprague View in CoL , Bull. Misc. Inform. Kew 1908 (6): 249. 1908. Type. Ecuador. Guayas: Chonona [“ Chonana ”] near Guayaquil, Dec 1861 (fl), R. Spruce 6260 bis (lectotype, here designated: K [K 000381141]!; isolectotype: K [K 000381140]!).

Type.

Based on Asterophorum eburneum Sprague.

Description.

Trees, 4–5 m tall. Leaves: petioles 1.8–3.7 cm long, leaf blades 15.5–40.5 × 7.5–18 cm, ovate, discolorous, bases truncate to subcordate, margins entire, apices acuminate, stellate trichomes above and below. Inflorescences long peduncled; flowers on second order axes. Capsules syncarpous, 2–2.5 cm long, subturbinate to turbinate, wings inconspicuous.

Distribution and habitat

(Fig. 2 View Figure 2 ). Endemic to Ecuador at 590–610 m elevation. Christiana eburnea occurs in areas of mangrove with influence of Savanna and Deciduous Forest. The report ( Dorr 1999) of C. eburnea occurring in Peru was based on the misidentification of a specimen (Schunke V. 5516) properly referred to C. mennegae (Jans.-Jac. & Westra) Kubitzki as reported by Barbosa-Silva et al. (2021).

Phenology.

Flowering specimens collected in December and fruiting in August.

Conservation status.

Christiana eburnea is known from two localities, with only one specimen found within a protected area (Reserva Ecológica Manglares Churute). With an AOO of 8 km 2, this species is assessed here as Critically Endangered (CR), under B 2 ab (ii, iv, v) criteria, according to IUCN (2012).

Vernacular names.

Unknown.

Etymology.

From the Latin ‘ eburneus, eborinus ’ meaning ivory-white with yellow tinge, a reference to the petal color according to the protologue.

Additional specimens examined.

Ecuador. Guayas: Naranjal, Reserva Ecologica Manglares – Churute, cerca a la Cumbre del Pancho Diablo de frente al Puerto de Gallo, 590 –– 610 m, 02 ° 25 ' S, 079 ° 35 ' W, 13 Aug 1992 (fr), C. E. Cerón 20141 ( US [00976599]); Ad fluvium Daule prope Guayaquil, s. d. (fl, fr), R. Spruce 6260 ( BM [BM 000554440; digital image], G [G 00356894], MPU [MPU 015290; digital image], P [P 02143013], W [1889-0106457]); Guayaquil, s. d. (fr), R. Spruce 6260 (P [P 02143014]).

Discussion.

Christiana eburnea is recognized by its fasciculate inflorescences with flowers arranged on second order axes and subturbinate to turbinate capsules, features that differentiate it from C. restingae .

This species was described as a novelty discovered in the Kew Herbarium (K) and its protologue states “ Ecuador. Chonana [sic] near Guayaquil, Spruce 6260. ” A specimen in Herbarium Hookerianum (K) labeled by Sprague “ Asterophorum eburneum, Sprague nov. gen et sp. Brownlowiearum ” has Sprague’s notes and sketches and the exact locality cited in the protologue but it is numbered “ 6260 bis. ” This specimen most closely matches the information given in the protologue and is designated here as the lectotype. We imagine that Sprague either miscopied the collection number or the word “ bis ” was added to the label later. Another specimen in Herbarium Hookerianum (K), also labeled by Sprague, has a copied label with the locality “ prope Guayaquil ” and the number 6260 bis. It clearly is a duplicate of the former.

Additional Spruce material ( BM, G, MPU, and P) labeled “ Ad fluvium Daule prope Guayaquil ” has the number “ 6260 ” as cited in the protologue but this material lacks the precise locality that was given even though Chonona, an indigenous locality, eventually was subsumed by the municipality of Daule ( Jijón y Camaño 1919). Given the locality conflict, these specimens are considered original but not type material. Finally, two herbarium sheets of Spruce 6260 in Paris (P 02143014 and P 02143015) lack original labels yet have Baillon’s sketches and notes; the latter sheet consisting of notes only.