Carya poilanei (A.Chev.) J.-F.Leroy, Rev. Int. Bot. Appl. Agric. Trop. 30: 428. 1950.

Zhang, Wei-Ping, Bai, Wei-Ning & Zhang, Da-Yong, 2022, The rediscovery of Carya poilanei (Juglandaceae) after 63 years reveals a new record from China, PhytoKeys 188, pp. 73-82 : 73

Carya poilanei (A.Chev.) J.-F.Leroy, Rev. Int. Bot. Appl. Agric. Trop. 30: 428. 1950.

Figures 2 , 3

Juglans poilanei A.Chev., Rev. Bot. Appl. Agric. Trop. 21: 496. 1941.

Type.

Vietnam. Lai-Chau province , within the great forest near the slopes of Pou-Nhou, in calcareous soil, at 1000 m. elev., 31 Dec. 1937, Poilane 26964, (Holotype: P [barcode P00605884, image!]; isotypes: P [barcode P00223582, P00605885, P00605886, image!]) .

Revised description.

Tree up to 15-40 m tall, deciduous, monoecious. Trunk to 0.5-2 m in diam.; bark smooth or somewhat rough, gray to whitish. Branches brown or gray-brown, initially with orange-yellow glandular and white pilose above, later almost glabrous and sparsely glandular, with roughish, scattered lenticels; pith solid in stem. Terminal buds 3-15 mm, both naked and with valvate scales, but the scales often drop easily, gray brown or brown. Leaf length 30-60 cm (incl. petiole), imparipinnate, soft green, papery; petiole 6-12 cm, enlarged at base, pubescent or glabrous; rachis pubescent or glabrous, sparsely glandular; leaflets (3 or) 5 (or 7), apical one shortly petiolulate, terminal petiolule 5-12 mm, lateral ones sessile or subsessile, broad obovate, occasionally obovate lanceolate or ovate-lanceolate, base skewed to nearly round, apex shortly obtuse or acuminate, margin serrate; adaxially smooth or finely scabrid, abaxially glabrous except for hairs along midvein and in axils of secondary veins, secondary vein 15-25 pairs, sometimes old leaflets blade densely covered with brown scales; apical and middle leaflets 25-40 × 12-20 cm, much larger than base leaflets. Flowers not seen. Fruits subglobose or compressed-globose, 2.8-3.2 × 3-3.5 cm, with peduncle, 1.5-6 cm length; husk wingless, sparely orange-glandular, shortly pubescent, 3.6-5.6 mm thick, moderate keels extending to middle, cracks into 3 or 4 petals when dried; shell subglobose, closely white tomentose, with 2 longitudinal ridges, apex slightly convex, 2.8-3.5 mm thick, cracks into 2-4 sections when dried, equal or unequal; 3, 4 or 6 chambered at base, lacunae present in the wall near the secondary septa. Flower unclear. Fruit Sep. Germination hypogeal.

Distribution.

China: Yunnan Province, Jianshui County; Vietnam: Lai-Chau Province, Pou-Nhou; Laos: Vientiane Province, Ban Mouang Cha (Muang Cha); Thailand: Chiang Mai (Chiengmai) Province, Fang District, Doi Pha Hom Pok Range (Fig. 1A ).

Habitat and ecology.

It grows on southeastern and southern slope of the limestone or calcareous mountain at an elevation of 1000-2050 m (Fig. 1B, C ). The three sites we discovered are in the subtropical region, on the eastern edge of Ailao Mountain, and 15 kilometers to the south are hot dry valleys (elevation about 200 m). Of these three distribution points, the closest distance between the two points is about 2 km, while the farthest is just about 6 km. Among the three threatened relic forests, C. poilanei are dominant and impressive trees.

Additional specimens examined.

China: Yunnan Province, Jianshui County, Potou Town, Dajinglaozhai Village , on limestone, 23°23'40.42"N, 102°51'34.42"E, 1895 m, 30 Jul. 2021, Zhang BNU20210730-1 (BNU, [barcode BNU0053602]) (Fig. 2 ), ibid., 23°23'42.33"N, 102°51'36.65"E, 1889 m, 31 Jul. 2021, Zhang 20210731-30 (BNU, KUN); Ximatang Village , on limestone, 23°24'5.68"N, 102°52'17.38"E, 2019 m, 31 Jul. 2021, Zhang 20210731-3 (BNU), ibid., 23°24'5.28"N, 102°52'11.25"E, 1980 m, 31 Jul. 2021, Zhang 20210731-14 (BNU); Yuchu Village , on limestone, 23°20'47.75"N, 102°51'35.90"E, 1892 m, 31 Jul. 2021, Zhang 20210731-17 (BNU, KUN), ibid., 23°21'44.46"N, 102°51'27.65"E, 1859 m, 5 Oct. 2021, Zhang 20211005-1 (BNU) . Laos: Vientiane Province, Ban Mouang Cha (Muang Cha), on rocky limestone hill, c. 1500 m, 16 Apr. 1932, Kerr 21092 (BM [barcode BM013822350, image!], K, P [barcode P06811763, image!]) . Thailand: Chiang Mai (Chiengmai) Province, Fang District, Doi Pha Hom Pok Range , 19°55'0.80"N, 99°12'52.20"E, 1100-1180 m, 23 Feb. 1958, Smitinand 4319 (L [barcode L0069301/L.1551797, image!]) .

Figures

Figure 1. Distribution and habitat of Carya poilanei (A. Chev.) J. - F. Leroy A four distribution sites in Yunnan province of China, Vietnam, Laos and Thailand. Red circle indicates the localities taken from the new record areas, and blue circles indicate historical distribution localities where the trees have been presumably extirpated B the limestone mountain habitat C eastern edge of Ailao Mountains, with human habitation in plateau. Red lines mark the boundary of the C. poilanei distribution in Dajinglaozhai Village.

Figure 2. Carya poilanei (A. Chev.) J. - F. Leroy (representative specimen, BNU 20210730 - 1, BNU).

Figure 3. Living plants of Carya poilanei (A. Chev.) J. - F. Leroy A tree B trunk, with a maximum diameter at breast height (DBH) of 1.97 m C sapling D twig E terminal buds (NB: naked buds; SB: buds with valvate scales) F petiole enlarged at base G leaf, showing 5 leaflets H leaf abaxial glabrous I leaf abaxial densely brown scales J fruiting branch K husk, showing base L husk, showing peduncle M husk, irregularly dehiscent N shell, vertical view O shell, lateral view P longitudinal section of nut Q-S transversal section of nuts, with 3, 4 and 6 chambers, respectively; lacunae present.