Ophiorrhiza shiqianensis L.D.Duan & Yun Lin, 2019

Duan, Lin-Dong, Lin, Yun & Lu, Zhen, 2019, Ophiorrhiza shiqianensis (Rubiaceae), a new species from Guizhou, China, PhytoKeys 121, pp. 43-51 : 44-46

Ophiorrhiza shiqianensis L.D.Duan & Yun Lin sp. nov. Figs 1 , 2 , 4 A–E

Diagnosis.

Similar to Ophiorrhiza hunanica H. S. Lo based on stems, leaves and capsules; differing from it by the stems which are glabrous, glabrescent or pilose, the 5-10 cm long subterranean stem internodes, the glabrous or pilose petioles, the 3-5 mm long stipules, the purple corolla tube and lobes, the ca. 12 mm long styles and the included stigmas in long-styled flowers, the 3-4 mm × 8-10 mm, glabrous or glabrescent capsules [vs. stems densely villose, subterranean stem internodes 1-2 cm long, petioles villose, stipules 5-15 mm long, corolla tube purple and corolla lobes white, style 15-17 mm long and stigmas exserted in long-styled flowers, capsules 5-6 mm × 10-12 mm, densely villose in Ophiorrhiza hunanica (Figs 3 , 4F )].

Type.

CHINA. Guizhou: Shiqian County, Pingshan Town, Fudingshan Nature Reserve, at sides of streams in dense evergreen broad-leaved forest in valley at 960 m elevation, 18 March 2014 (fl), L.D. Duan, Z. Lu & Q. Lin 5805 (holotype: PE!, Herb. Bar. Code No. 02232812; isotypes HUFD! (=Herbarium, Hunan Food and Drug Vocational College, Hunan, China), HUSY! (=Herbarium, Shaoyang University, Hunan, China) IBSC!, K!, KUN!, PE!).

Description.

Perennial herbs, 10-30 cm tall, repent at base. Stems erect, fleshy, green, brown to black after drying, glabrous, glabrescent or pilose; subterranean stems glabrous with 5-10 cm long internodes. Leaves: petioles 1.5-4.0 cm long, glabrous or pilose; blades papery after drying, elliptic or obovate-elliptic, 7-17 cm × 3-7.5 cm, adaxially pilose, abaxially pilose on veins, base cuneate, apex obtuse to subacute; secondary veins 9-11 pairs; stipules often persistent, ovate to ovate-lanceolate, 3-5 mm long, ciliate. Inflorescence cymose, terminal, 2- to 10-flowered, densely villose, pendulous; peduncle 2.5-4 cm long when flowering, 8-10 cm long when fruiting, arching, densely villose. Bracts linear-lanceolate, 9-10 mm long, ciliate; bracteoles linear, 4-5 mm long, ciliate. Flowers distylous, pedicels 1-2 mm long, densely covered with hairs. Calyx with hypanthium compressed-turbinate, 2.5-3 mm long, 5-ribbed, densely covered with hairs; lobes 5, lanceolate-linear, 5-6 mm long, ciliate. Corolla tube and lobes purple, funnel-form, outside glabrous, inside pubescent; tube 1.7-1.8 cm long; lobes 5, ovate-triangular, 4-6 mm long, apex rostrate. Stamens 5, inserted near throat and exserted at anthesis in short-styled flowers or inserted below middle of corolla tube and included at anthesis in long-styled flowers; filaments 1.5-2 mm long in short-styled or ca. 1 mm long in long-styled flowers; anthers ca. 2.5 mm long, dorsifixed. Ovary 2-celled, ovules numerous in each cell; style ca. 12 mm long in long-styled or 7-7.5 mm long in short-styled flowers; stigmas 2, linear in short-styled or subcapitate in long-styled flowers, included in both morphs. Capsules purple, mitriform, strongly laterally compressed, 3-4 mm × 8-10 mm, pilose or glabrescent. Seeds numerous.

Phenology.

Plants were observed in full bloom on 18 March 2014 and with ripe fruits on 12 May 2014 and neither flowers nor fruits were seen on 12 August 2011. It can be expected that the flowering time of the new species is from March to April and that fruiting time is from April to June.

Habitat.

The species grows on the banks of streams in dense broad-leaved forest in valleys at elevations of 960-1100 m.

Distribution.

Ophiorrhiza shiqianensis is only known from two localities in Shiqian County, northeast Guizhou Province, southwest China, notably: Fudingshan Nature Reserve, Pingshan Town and Nishan Village, Ganxi Town.

Etymology.

Ophiorrhiza shiqianensis is named after its type locality, Shiqian County, northeast Guizhou Province, southwest China.

Vernacular name.

Shi qian she gen cao in Chinese Pinyin.

Preliminary conservation status.

Ophiorrhiza shiqianensis is only known from four collections in two locations, Fudingshan Nature Reserve (well protected, 152 km2) and Nishan Village (ca. 50 km2). It comprises about 200 individuals (criteria D1 ≤ 250) growing in ten populations. This new species can be assessed as Endangered (EN) according to the IUCN Red List Categories and Criteria ( IUCN 2001, 2012). However, it is possible that more populations could be found in similar habitats of mountain areas of Zhenyuan, Yuqing and Shibing Counties in northeast Guizhou. With limited fieldwork at present, we would temporarily consider this new species to be Vulnerable (VU) based on criteria D1 and D2.

Additional specimens of Ophiorrhiza shiqianensis (paratypes).

CHINA. Guizhou: Shiqian County, Ganxi Town, Nishan Village, Niujinshan, stream-sides in dense evergreen broad-leaved forest in valley at 1100 m elevation, 12 August 2011 (sterile), L. D. Duan, Z. Lu & Q. Lin 5356 (HUFD!, HUSY!, PE!); Pingshan Town, Fudingshan Nature Reserve, stream-sides in dense evergreen broad-leaved forest in valley at 960 m elevation, 18 March 2014 (fl), L. D. Duan, Z. Lu & Q. Lin 5808 (HUFD!, HUSY!, PE!); same locality, 12 May 2014 (fr), L. D. Duan, Z. Lu & Q. Lin 5809 (HUFD!, HUSY!, IBSC!, K!, KUN!, PE!).

Critical note.

The new species most resembles Ophiorrhiza hunanica . Detailed morphological differences between the two species are given in Table 1 .

Figures

Figure 1. Ophiorrhiza shiqianensis. A habit of flowering plant B section of stem, showing stipules C inflorescence D flower E long-styled flower F pistil in a long-styled flower G short-styled flower H capsule A-F from L. D. Duan, Z. Lu & Q. Lin 5805 G from L. D. Duan, Z. Lu & Q. Lin 5808 H from L. D. Duan, Z. Lu & Q. Lin 5809.

Figure 2. Ophiorrhiza shiqianensis. Isotype, showing subterranean stem internodes 5 - 10 cm long and inflorescences 2 - to 10 - flowered.

Figure 3. Ophiorrhiza hunanica. Neotype (designated by Duan et al. 2014), showing subterranean stem internodes 1 - 2 cm long and inflorescences 5 - to many-flowered.

Figure 4. Ophiorrhiza shiqianensis (A-E) and O. hunanica (F). A Habit of flowering plant B Inflorescence C long-styled flower D short-styled flower E capsule F habit of flowering plant, showing white corolla lobes.