Notes on the genus Syzygium (Myrtaceae) from Cambodia, Thailand, Vietnam, China and Taiwan Author Chantaranothai, Pranom 0000-0002-5065-6169 Applied Taxonomic Research Center (ATRC) and Centre of Excellence on Biodiversity (BDC), Department of Biology, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand & Royal Botanic Gardens, Kew, Richmond, Surrey TW 9 3 AE, UK text PhytoKeys 2024 2024-07-11 244 151 161 journal article 299706 10.3897/phytokeys.244.118657 0dde5265-4a83-4864-a6a9-471b7640af21 Syzygium foxworthianum (Ridl.) Merr. & L. M. Perry , Mem. Mer. Acad. Arts 18: 168. 1939 . Eugenia foxworthyi Ridl. , Fl. Mal. Penins. 1: 728. 1922, non Elmer, 1912 . Eugenia foxworthiana Ridl. , Fl. Mal. Penins. 5: 308. 1925. Type: Peninsular Malaysia , Pahang , Bukit Goh Reserve, 12 Jan. 1920 , Foxworthy Field No. 3624 ( lectotype , designated by Chantaranothai and Parnell 1994 , p. 63: K [K 001005521]). Syzygium foxworthianum (Ridl.) Masam. , Enum. Phan. Born.: 528. 1942 . Eugenia densiflora Miq. var. angustifolia Ridl. , Fl. Mal. Penins. 1: 729. 1922. Type: Peninsular Malaysia , Perak , Ulu Temengoh, Ridley s. n. ( lectotype , designated here: K [without barcode]). Syzygium pycnanthum Merr. & L. M. Perry var. angustifolium (Ridl.) P. S. Ashton, Tree Fl Sabah & Sarawak 7: 270. 2011 . Type. Based on Eugena foxworthiana Ridl. Distribution. Thailand , Peninsular Malaysia , Sumatra, Borneo, Vietnam ( Lao Cai (Laokhay), Pakha, 10 Dec. 1935 , Poilane 25052 (K). Ecology. In evergreen forest, 50–200 m alt. Notes. Ashton (2011) placed S. foxworthianum under S. pycnanthum ( Eugenia densiflora Miq. ) but I do not agree with this placement because the former differs from the latter by having a long and lax inflorescence (vs short and dense), slightly smaller and narrower leaves, 16–18.5 × 4–6.5 cm (vs larger and broader, 17.5–26 × 4.5–8.5 cm ), two intramarginal veins, sometimes without the intramarginal vein and secondary veins ascending to a shallow loop (vs 2–3 intramarginal veins). Although the Vietnamese specimen Poilane 25052 (K), has young fruits, I found that it belongs to S. foxworthianum . Therefore, it is a new record of this species for Vietnam . Eugenia densiflora var. angustifolia Ridl. was described based on two specimens from Peninsular Malaysia , Peak ( Ridley s. n .) and Kelantan ( Yapp s. n .). Ridley s. n . (K) is available and is designated here as the lectotype .