Primulina guizhongensis Bo Zhao, B.Pan & F.Wen, 2013

Zhao, Bo, Pan, Bo, Zhang, Yang & Wen, Fang, 2013, Primulina guizhongensis (Gesneriaceae), a new species from Guangxi, China, Phytotaxa 109 (1), pp. 27-35 : 32-33

Primulina guizhongensis Bo Zhao, B.Pan & F.Wen , sp. nov. ( Figure 2 & Figure 3 A–F )

The new species differs from P. spadiciformis by having smaller green linear-lanceolate bracts (0.8–1.2 cm long), longer pedicels (1.8–2.2 cm long), larger calyx lobes (11–15 × 1.5–1.8 mm), corollas outside with glandular pubescence, inside glabrous.

TYPE:— CHINA. Guangxi Zhuang Autonomous Region: Liuzhou , Liujiang County, Futang Town , 24°20'24.81"N, 109°12'33.3036"E, 130 m, 10 October 2007, WF071001 (holotype IBK!, isotype BJFC!)

Perennial herbs, acaulescent. Rhizomes cylindrical, ca. 3.5 cm long or longer, 0.6–0.9 cm in diameter, glabrous, internodes inconspicuous. Leaves basal, 20–32 or more; petioles cylindrical, pubescent, 3.5–8.5 cm long; leaf blades slightly oblique, ovate to oblong-ovate, 5.5–10.5 × 2.1–4.5 cm, chartaceous when dry, densely white appressed-pubescent on both sides, bases cuneate or narrowly cuneate, margins subentire, repand or crenate, apices obtuse or rounded; lateral veins 3–4 on each side of midrib, conspicuous. Cymes axillary, 4–12 or more, unbranched, commonly 2–4-flowered, rarely 1; peduncles purplish brown, slender, 5.5–10.5 cm, 0.18–0.25 cm in diameter, densely erect puberulent; bracts 2, opposite, linear-lanceolate, 0.8–1.2 × 0.1–0.15 cm, green, outside puberulent, margins entire, apices acute. Pedicels purplish-brown or greenishbrown, 1.8–2.2 cm long, 1.5–2.0 mm in diameter, puberulent and sparsely assurgent, villose. Calyx lightly purplish brown, 5-sect from base; segments equal, lanceolate, 11–15 × 1.5–1.8 mm, outside densely pubescent, inside glabrous, margins entire, apices acute. Corolla bluish purple to lilac, campanulate, 4.0– 4.8 cm long, outside glandular puberulent, inside glabrous; limb distinctly 2-lipped, adaxial lip 2-parted to the middle, lobes slightly oblique broadly ovate, ovate to rounded, ca. 0.95–1.1 × 0.5–1.0 cm, 3-lobed to or over the middle, lobes oblong, the apex of central one emarginate, 12.0–13.3 × 8–9 mm, rounded at apex. Stamens 2, adnate to ca 1.0 cm above the corolla base; anthers reniform, 3.2–3.5 × 0.8–1.1 mm, slightly constricted at the middle, glabrous; filaments geniculate at the middle, ca. 13 mm long, glabrous; staminodes 3, lateral ones short linear, glabrous, 4.0– 4.5 mm long, adnate to 0.8–1.0 mm above the corolla base, the central one linear, ca. 0.5 mm long, adnate to ca 4.2 mm above the corolla base; disc annular, margin entire, 0.4–0.5 mm high. Pistil 4.2–4.5 cm long; the transition between ovary and style inconspicuous, densely glandular-puberulent and puberulent. Stigma pale greene, obtrapeziform, apex 2-lobed to about one-third of the stigma, ca. 4.5 mm long, lobes triangular. Capsules linear, 3.5–4.0 cm long.

Habitat and distribution:— Primulina guizhongensis was found growing on the slopes and cliffs of some limestone hills and at the entrance of limestone caves, often at crevices in open evergreen forest near Futang town, Liujiang County, Guangxi, China. The region has a seasonal monsoon climate. The distribution of this new species and its relatives P. spadiciformis , P. mollifolia and P. luochengensis are shown in map 1.

Etymology:— GUI is the abbreviation for Guangxi Zhuang Autonomous Region. The epithet refers to the type locality of this new species being located in the center of Guangxi.

Diagnostic characters:— Primulina guizhongensis differs from its P. spadiciformis in having smaller green linear-lanceolate bracts, longer pedicel (1.8–2.2 cm long), larger calyx lobes (11–15 × 1.5–1.8 mm), and different corolla indumentum. A detailed comparison of the remarkable characters of two relatives is shown in table 2.

Conservation status:— We carefully investigated the type locality on five visits during four years. Primulina guizhongensis appears to be restricted to limestone hills surrounding Futang Town. Although this species is common on local limestone hills, the habitats are too concentrated to those populations are easy to be threatened by local people’s activities and this region is not a natural reserve. Using the IUCN Red List categories and criteria version 3.1 (IUCN 2001), a provisional conservation status of Vulnerable VU D1 is assessed for this species.

MAP 1. Distribution of Primulina guizhongensis and related taxa. A, Known distribution of P. guizhongensis ; B, Probable distribution of P. spadiciformis ; C, Known distribution of P. mollifolia ; D, Known distribution of P. luochengensis

Figures

FIGURE 2. Primulina guizhongensis. A, habitat; B, opened corolla for showing stamens and staminodes; C, calyx, pistil and stigma (Drawn by Qi Wei based on holotype).

FIGURE 3. The comparison of morphology between two relatives (A–F) Primulina guizhongensis (G–J) P. spadiciformis A, habitat; B, plants; C, the frontal view of flower; D, the lateral view of flower; E, pistil and calyx; F, opened corolla; G, Habitat; H, plant in flowering time; I, the frontal view of flower; J, the lateral view of flower.