Lysimachia cavicola Y.Nong & Y.G.Wen sp. nov.

Figs 1, 2, 3, 4

Chinese name.

dòng shēng xiāng cǎo (洞生香草).

Diagnosis.

Lysimachia cavicola shares several similarities with L. microcarpa C.Y.Wu, L. fooningensis C.Y.Wu, and L. capillipes Hemsl., including leaves alternate, flowers solitary in leaf axils, corolla yellow, anthers longer than filaments with distinct basifixation, and typically opening by apical pores, along with capsules dehiscing by valves. However, the new species can be easily distinguished by the following characteristics: stems solitary or clustered in 1-2, herbaceous and densely glandular; leaves ovate or elliptical lanceolate with inconspicuously reticulate veins; petioles 2-4 mm long that are minutely glandular hairy; capsules globose, 2-3 mm in diam., about the same length as the calyx. A more detailed morphological differences among the four species is presented in Table 1.

Type.

China. Guangxi: Fengshan, limestone cave entrance, 24°34'17"N, 106°50'31"E, alt. 794 m, 23 April 2021 (fl.), R.C. Hu HRC210423003 (holotype, GXMI!; isotypes, IBK!).

Description.

A perennial, herbaceous, 4-15 cm tall, aromatic when dry. Stems erect, solitary or 1-2 in clusters, terete and densely glandular. Leaves alternate: lamina ovate or elliptical lanceolate, 1.5-3(-4) × 0.5-1.6 cm, base attenuate, apex acuminate, glabrous except densely glandular hairy on midrid abaxially, veinlets invisible; petiole 2-4 mm long, minutely glandular. Flowers 5-merous, solitary, axillary at upper part of leaf axil; pedicel filiform, 2-4 cm long, sparsely glandular hairy; calyx green at flowering, lobes deeply parted, ovate-lanceolate, c. 2 mm long, glabrous except sparsely glandular abaxially and margin; corolla yellow, lobes deeply parted, narrowly elliptic or narrowly oblong, 6-8 × 1- 2 mm, apex recurved downward, glabrous on both surfaces; filaments short, not more than half the length of anthers, filaments connate basally into c. 1 mm high ring, free parts 1 mm; anthers 4 mm long, basifixed, opening by apical pores. Capsule globose, 2-3 × 2-3 mm, chalky, brittle, split into 5-valved, calyx yellowish-white in fruiting.

Phenology.

Flowering in April-May; fruiting in June-July.

Etymology.

Fengshan, situated in the southwest of Guangxi, China, is a biodiversity hotspot known for its remarkable discoveries of new species (Nong et al. 2010; Wen et al. 2012; Li et al. 2019). One such species, Lysimachia cavicola, was found at the cave entrance in Fengshan, and the specific epithet is named after its habitat.

Distribution and habit.

The new species is currently known only from the type locality from the southwest of Guangxi, China (Fig. 5). The new species mainly occurs at elevations of 800 m and it grows at the entrance of caves.

IUCN Red list category.

Data Deficient (DD). Data available for the new species are still insufficient to assess its conservation status. According to the IUCN criteria (IUCN 2022), it is considered Data Deficient until further information becomes available. Although Lysimachia cavicola currently has relatively good growth, further collecting and monitoring is necessary to allow more conclusive estimations about its rarity and vulnerability for future conservation planning of this species.

Additional specimen.

China. Guangxi: Fengshan, limestone cave entrance, 24°34'17"N, 106°50'31"E, alt. 794 m, 19 June 2023 (fr.), You Nong NY20230619001 (GXMI!).