Aristolochia obliqua S.M. Hwang (1981: 226)

Zhu, Xin-Xin, Liao, Shuai, Ma, Zheng-Xu, Xu, Bo, Wang, Zhang-Hua, Wang, Yuan & Ma, Jin- Shuang, 2017, The taxonomic revision of Asian Aristolochia (Aristolochiaceae) III: Two new taxa of Aristolochia and morphological revision for the flower character of A. obliqua from Yunnan, China, Phytotaxa 332 (3), pp. 269-279 : 276-277

Aristolochia obliqua S.M. Hwang (1981: 226) ( Figs. 6 A–B & 7 )

This species was published by Hwang in 1981 with a diagnosis, that it is similar to Aristolochia cucurbitoides C.F. Liang (1975: 15) but can be distinguished by its oblique and unilaterally 3-lobed limb, and ovate or ovate-lanceolate lobes. A detailed description and distinct sketch were also provided in the protologue. This description was subsequently adopted by Hwang (1988), Ma (1989: 350 & Fig. 2-G ), Tao (1997) and Hwang et al. (2003), but character of the limb is quite different in the sketch of Tao’s publication (1997: Fig. 3 –8). In order to figure out the correct flower character of the species, we made careful examination of several publications (including protologue), numerous specimens (including types), live plant photos of Aristolochia obliqua and A. cucurbitoides . Unfortunately, the oblique and unilaterally 3- lobed limb can not be found in the specimens and live plants of Aristolochia in China.

However, we collected one species of Aristolochia at Cikai Town (Gongshan County, Yunnan), about 30 km as the crow flies from Bingzhongluo (named Yi district in the past) where is the type locality. Except for the limb, all other characters of the collected species at Cikai Town are similar to the corresponding characters in the protologue and the type specimen of Aristolochia obliqua ; limb of the collected species at Cikai Town is the same as the limb in the type specimen of A. obliqua . Hence, we conclude that character of the limb in the past publications (including protologue) was wrongly described and illustrated. Then, it is revised here as below: limb deeply 3-lobed, slightly asymmetric, lobes triangular-ovate, straight. Detailed morphological comparison between A. obliqua and A. cucurbitoides is shown in Table 3 and Fig. 6 . We also provide with the sketches mentioned above and color photos taken by us in Fig. 7. A . obliqua is also similar to A. utriformis S.M. Hwang (1981: 228) in the leaf shape, but it differs from the latter in the shape of calyx limb, which is also compared in Table 3.

Specimens of A. obliqua examined: — CHINA. Yunnan: Gongshan County, 6 June 1960, N.W. Yunnan Exped. 9267 (isotype PEM), 8 May 1979, Nujiang Exped. 79-0054 (KUN), 8 May 2014, Z.H.Wang et al. WZH012 (CSH).

Specimens of A. cucurbitoides examined: — CHINA. Guangxi: Tianlin County, 18 April 1963, Q. H.Lv 2229 (type IBK) ; Leye County, 9 April 2016, Y. F.Huang & H.Tang HYF160409002 ( GXMI) .

Specimens of A. utriformis examined: — CHINA. Yunnan: Wenshan County, 24 April 1962, K.M.Feng 22057 (PEM), 24 November 1985, J.S.Ma 477 (PEM), 24 November 1985, J.S.Ma 478 (PEM), 24 November 1985, J.S.Ma 480 (PEM).

Figures

FIGURE 2. A–H: Aristolochia involuta. A. Habit, B. Leaf, C–D. Flower, E. Longitudinal-section of flower (showing inside structure), F. Anthers and gynostemium, G. Capsule, H. Seed. I–J: A. bambusifolia. I. Habit, J. Flower. (A–H: photographed by X.X.Zhu; I–J: photographed by Y.Liu.)

FIGURE 3. Holotype of Aristolochia involuta (CSH-0137427).

FIGURE 6. A–B: Aristolochia obliqua. A. Isotype (PEM-0001971), B. Enlarged photo of flower from the isotype (PEM-0001971). C–D: A. cucurbitoides. C. Type (IBK-00190363), D. Enlarged photo of flower from the type (IBK-00190363).

FIGURE 7. Aristolochia obliqua. A. Habit, B–C. Flower, D–E. The flower sketch. (A: photographed by Z.H.Wang; B–C: photographed by Y.Wang; D: quoted from Hwang 1981; E: quoted from Tao 1997.)