Hullettia King ex Hook.

Bui, Van Huong, Vu, Dinh Duy, Pham, Mai Huong, Do, Van Hai, Doan, Hoang Son, Bui, Van Thanh, Dam, Ngoc Anh Luu, Truong, Ba Vuong & Gardner, Elliot M., 2022, HULLETTIA King ex Hook. f. (Moraceae), A newly recorded genus to the Flora of Vietnam, with its lectotypification and a revised key to Vietnamese Moraceae, Phytotaxa 550 (3), pp. 272-278 : 275

Hullettia King ex Hook. f.,

Fl. Brit. India 5(15): 547. 1888; King, Ann. Roy. Bot. Gard. (Calcutta) 5 (2): 163. tab. 197. 1896; Engl. in Engler & Prantl, Nat. Pflanzenfarm. Nachtr. II-IV: 122. 1897; Boerl. Handl. Fl. Ned. Ind. 3: 338, 372. 1900; Ridley, Fl. Malay Penin. 3: 358. 1924; Jarrett, Jour. Arnold Arbor. 40: 9, 11. fig. 2 (g-k), fig. 3 (j-l). 1959; id. 41: 334. 1960; C. C. Berg et al., Fl. Males., Ser. 1, Spermat. 17 (1): 126. 2006.

Lectotype: Hullettia griffithiana (Kurz) Hook. f. [designated by Jarrett, Journ. Arnold Arbor. 41: 334. 1960 ].

Shrubs to small trees, monoecious. Leaves spirally arranged; simple, entire, lamina pinnately veined. Stipules paired, linear, lateral, scars small, round. Inflorescences unisexual, solitary or pairs in leaf axils, capitate, head pulvinate or obconical at anthesis , becoming subglobose in syncarp, pedunculate; stamens or ovaries sunken in cavities closely set on the upper surface of the receptacle; receptacle naked (perianths and interfloral bracts lacking), fleshy; involucre of 3-6 obtuse to lanceolate, flattened bracts present. At anthesis : anthers or stigmas exserted through perforations in the upper surface of the receptacle; involucre marginal; male head with up to 30 flowers; stamens paired in each cavity with the filaments partially or almost completely united, long-exserted; female head with up to 6 flowers, ovaries solitary in each cavity, unilocular, the style apical with a short-exserted, capitate stigma, the ovule apical. Mature syncarp formed by the enlargement of the entire female head, with 2-6 flowers forming fruit and completely filling the receptacle; involucre equatorial or becoming sub-basal through the greater expansion of the upper surface of the receptacle; mature ovary pergamentaceous, scar left by the style apical, the seed large, attached apically, testa membranous except the thickened apical cap, endosperm none, embryo straight, orientation longitudinal, cotyledons equal, appressed faces at an angle of 0-90° to median plane of ovary, radicle and plumule small.

This genus comprises two species and ranges from Southern Myanmar (Tenasserim), Vietnam, and Thailand, to the Malay Peninsula and Sumatra (Indragiri).