S. x zhongcairongii Y. S. Wang & S. H. Shi nothosp. nov. Figure 1

Material.

Dongzhai Harbour, mangrove forest Hainan Island, China (Fig. 1A), 19°58'12"N, 110°34'48"E, 13 June 2018, Cairong Zhong, No. Saa20180613-001 (Holotype: IBSC; Isotype: IBSC).

Morphological traits.

Trees, evergreen, 10-12 m tall, highly branched (Fig. 2A). Bark smooth or lightly fissured flaky, dark grey to pale fleshy green; stem base simple. Leaves simple, opposite, leaf blade leathery, glabrous, pale green, elliptical, 2-9 cm long,1-5 cm wide, apex obtuse, base acuminate, margin entire; petiole 0.3-1 cm; stipules absent. Inflorescence terminal or axillary, 1-3 or 1-5 flowered dichasia; flower bud ellipsoidal, 1.5-2.4 cm in length, 1-1.5 cm width, constricted medially, green, glossy, smooth, slightly angular; Calyx cup-shaped, lobes 4-6, wide ovate (0.8-1.2 cm long, 0.5-0.8 cm wide), apex acute, inner often fleshy green inside. Petals absent; stamens numerous along calyx, white, 1-1.5 cm in length; stigma peltate to 5 mm wide. Fruits not developed.

Distribution.

The hybrid is currently found only in Dongzhai Harbour within an area of 48 m2, mangrove forest, Hainan Island, China.

Habitat and ecology.

The hybrid grows in a mangrove forest.

Phenology.

The new hybrid flowered from the beginning of March to the end of October.

Conservation status.

The new hybrid S. x zhongcairongii was collected only from the mangrove forest in Dongzhai Harbour. At this site, only two individuals were observed.