Toxicopueraria yunnanensis (Franch.) Egan, Ashley N. & Pan, Bo, 2015

Egan, Ashley N. & Pan, Bo, 2015, Resolution of polyphyly in Pueraria (Leguminosae, Papilionoideae): The creation of two new genera, Haymondia and Toxicopueraria, the resurrection of Neustanthus, and a new combination in Teyleria, Phytotaxa 218 (3), pp. 201-226 : 218

Toxicopueraria yunnanensis (Franch.) A.N.Egan & B.Pan, comb. nov.

TYPE: — CHINA. Yunnan. woods near Tapintze. April 1883 Delavay 506 (lectotype: P[barcode P00507990!]; isolectotypes: P[barcodes P02961048!, P00507992]) Lectotype designated by Z. F. Le and X. Y. Zhu (Ann. Bot. Fenn. 46: 419–424. 2009).

Basionym: — Pueraria yunnanensis Franchet, Pl. Delav. 181. 1890.

Selected Synonyms: — Derris bonatiana Pampanini, Nuovo Giorn. Bot. Ital. , n.s. 17(1): 8. 1910 (lectotype: NY[barcode NY00007612!]; paratypes: Maire 210 P[barcode P02961022!])

Images: —Photo Plate ( T. peduncularis & T. yunnanensis ): Figure 8 .

Description: —Woody climber. Leaves and stems glabrous or thinly pubescent or glabrescent. Petioles 3–8 cm; stipules with two small spur-like projections below the stipules, 1–2 mm, these becoming woody with age; leaflets with sparse hairs, apex caudate-acuminate, base rounded. Pseudoracemes 10–25 cm long. Flowers white or cream, not suffused with purple or pink, (2–)3–6(–7) flowers clustered at nodes of rachis; pedicels slender, 2–8 mm. Calyx membranaceous, subglabrate, sparsely villous; upper 2 lobes connate entirely, apex of lobes obtuse. Vexillum orbicular-ovate; 11–13 mm × ca. 8 mm; auricles inflexed; wings oblong, (7–) 9–13 mm × 3–4 mm, claw ca. 4 mm long; keel petals (6–) 7–12 mm × 3–4 mm, claw ca. 4 mm long, apex obtuse. Fruits linear, tan when mature, 4–8 cm × 7–11 mm. Seeds kidney-shaped to elliptic, ca. 5 × 3 mm, compressed, red-brown to black.

Phenology: —Flowering April to June; fruiting May to July.

Distribution and Ecology: —Endemic to Southwest China (Chongqing, Guangxi, Guizhou, Sichuan, Yunnan). Forests and forest margins or in thickets. Elevation 800–2300 m.

Conservation: — Toxicopueraria yunnanensis is endemic to five provinces in southwestern China and is less common than its congener. It is assessed here as Least Concern (LC) according to the criteria of IUCN (2001) due to its fairly wide distribution, but a more detailed study would be beneficial to accurately determine the conservation status.

Discussion: — Toxicopueraria yunnanensis has been synonymized with T. peduncularis by a number of taxonomists ( Lackey, 1977b; van der Maesen, 1985, 1994, 2002; D. Wu & Thulin, 2010; T. L. Wu, 1995) because of their morphological similarities. However, they differ in indumentum, flower color, petal shape, projections below the stipules, and phenology ( Figure 8 ). In addition, Le and Zhu (2009) found leaf epidermis and seed coat micro-characters to support the separation of these two species. From experience, the authors can easily determine T. yunnanensis from T. peduncularis in both live and pressed specimens, particularly in flower. Toxicopueraria yunnanensis tends to have a more upright vexillum with sides reflexed backwards whereas in T. peduncularis the whole vexillum is strongly reflexed, often to touch the calyx. Toxicopueraria yunnanensis has wing petals that are equal to or slightly longer than the keel, with the wings often displayed in a plane more perpendicular to the sides of the keel and with the ends curving backwards, presenting a more open display. In comparison, T. peduncularis has wing petals that are equal to or slightly shorter than the keel, and that are usually straight or slightly curved outward but more often in a plane parallel to the sides of the keel (compare Figure 8A and 8C ). Furthermore, T. yunnanensis has small, spur-like projections that flank the stipule or stipular scar, these often becoming woody with age (see Figure 8C ). These are lacking in T. peduncularis .

Several issues concerning types of T. yunnanensis or its synonyms exist. Van der Maesen (1985) designated one collection at P as the holotype of Pueraria yunnanensis (barcode P00507990), listing another as an isotype. Le & Zhu (2009) found issue with van der Maesen’s designation of a holotype because there is no specification by the author/ collector, J.M. Delavay, as to which of his collections, all designated under number 506 but collected during April or August 1883 or 1885, was to act as the holotype. Therefore, Le & Zhu (2009) correctly determined the specimen selected by van der Maesen as the lectotype, relegating all other sheets of Delavay 506 (albeit with different dates) as isolectotypes.

In addition, there is some confusion surrounding the types of Derris bonatiana . The protologue states the type as “Yunnan-sen, source du Pe-long-tan. 8 May, 1904 (Ducloux, n. 377); [sine loco] (Maire, n. 210).” A search of Ducloux collections at Paris showed that Ducloux numbers 362–399 were collected from “Environs de Yun Nan Sen” during August and September of 1897, suggesting that Ducloux 377 would have been collected during this time frame as well. While doing research for this manuscript, A.N. Egan came across a specimen from Paris [P02961736] collected by Ducloux (no. 2301) on 8 May 1904 from “Yun-Nan: environs de Yun nan-sen”, written in Ducloux’s own hand. A survey of Paris’ Ducloux numbers from 2273 to 2504 includes specimens collected from January to May of 1904, a range that includes that stated in the protologue. Because the institution of deposition of the specimen cited in the protologue was not named ( Pampanini, 1910), van der Maesen (1985) designated a lectotype: “ China, Yunnan-sen, source of the Pe-long-tan river, 8 May 1904, Ducloux 377 (FI, holo, not seen).” This is the same information stated in the protologue, but with the addition of a location (FI, a place of employment of R. Pampanini, author of Derris bonatiana ). Note that van der Maesen did not actually see the specimen he designated as the lectotype. Attempts by author A.N. Egan to contact curators at FI concerning a Ducloux 377 collection in their herbarium were unsuccessful. As of 18 May 2015, JStor Global Plants includes a type specimen of Derris bonatiana from NY [NY00007612], but the kind of type is not specified. The typed label of the NY Ducloux 377 collection states: “ Derris botaniana Pampanini n.sp., Yunnan Sen, source de Pé, 377 (E.E. Maire?)” The typed font of “E.E. Maire?” is crossed out in pencil with “ Ducloux! ” handwritten above it. E.E. Maire was a French contemporary of F. Ducloux who spent time in Yunnan as a missionary and began collecting plants in 1905. Thus, there is confusion concerning the type information stated in the protologue and how its matches with various collections in herbaria around the world. The above body of research suggests that Ducloux and Maire collections may have been mixed up or either the date of collection or the collection number or the collector where misstated in the protologue. Until it can be determined whether a Ducloux 377 specimen exists in FI, the type designations of D. bonatiana are dubious.

Figures

FIGURE 8. Toxicopueraria yunnanensis (A–C) & T. peduncularis (D–F). A. Flowers. B. Inflorescences.C. Young, axillary inflorescence, leaf, and appendages flanking the stipule. D. Flowers. E. Young fruits. F. Habit, inflorescence, and leaves. Photographs by Bo Pan.