Aspidistra daibuensis Hayata var. longkiauensis C.T.Lu, M.J.Yang & J.C.Wang, 2023

Lu, Chang-Tse, Yang, Ming-Jen, Luo, Min-Xin & Wang, Jenn-Che, 2023, Aspidistra daibuensis var. longkiauensis, a new variety of Aspidistra (Asparagaceae) from Taiwan, identified through morphological and genetic analyses, PhytoKeys 222, pp. 129-151 : 129

Aspidistra daibuensis Hayata var. longkiauensis C.T.Lu, M.J.Yang & J.C.Wang var. nov.

Figs 5A-G , 6 Chinese name: 瑯嶠蜘蛛抱蛋

Diagnosis.

This new variety is similar to A. daibuensis Hayata var. daibuensis but can be distinguished by its shorter leaf length (72.24 ± 11.68 cm vs. 95.46 ± 21.04 cm), smaller ratio of the leaf blade length to width (3.73 ± 1.43 vs. 8.05 ± 1.73), thinner perianth lobe (1.28 ± 0.38 mm vs. 2.79 ± 0.64 mm), longer curve length of the stigma surface (10.98 ± 1.38 mm vs. 16.23 ± 1.45 mm), and larger ratio of the pistil height to stamen height (2.49 ± 0.59 vs. 2.03 ± 0.78). It also resembles A. mushaensis Hayata var. mushaensis but differs by its smaller ratio of the leaf blade length to width (3.73 ± 1.43 vs. 7.66 ± 1.35), narrower perianth lobe base (5.12 ± 1.12 mm vs. 7.27 ± 1.19 mm), and larger ratio of the pistil height to the stamen height (2.49 ± 0.59 vs. 1.59 ± 0.26).

Type.

Taiwan. Pintung County, Shuangliou national forest recreation area, Banyan trail, elev. 200-300 m, 12 Jun 2020, M.J.Yang s.n. (holotype: TAIF; isotype: TNU) .

Description.

Perennial evergreen herb. Rhizome creeping, 1-1.2 cm in diameter. Internode 0.2-0.4 cm. Cataphylls 3 to 4. Leaves: coriaceous, solitary or rare 2 tufts leaves, blade dark green occasionally with yellow spots; leaf margin with white serrulate, parallel venation; petioles 9.6-36.6 cm long; blade oblanceolate, blade oblique, 40.5-61.8 cm long, 4.6-8.6 cm wide, acute at apex,. Flower solitary, bisexual, scape 0.3-4.0 cm long, 3-6 bracts, bract ovate; perianth urceolate to campanulate, fleshy, perianth tube purple, basal white, 13.5-20.5 mm long, 8.5-15.5 mm wide; perianth lobe 7-9, sometimes yellow at apex, ovate triangular, 5-10 mm long, base 3.2-7.4 mm wide, 0.7-2.0 mm thickness, lobe center with two keels, lobe margin with two keels conspicuous. Stamens 7-9 as many as the perianth lobe, inserted at the perianth tube base or near base; anther oblong, 1.3-3.0 mm long; anther connective absent; filament short, 1-2 mm. Pistil 5-8 mm; stigma disk-like, 4 to 5 lobes, conical and lobe marginal concave, stigma nearly covering the perianth tube, 7.6-12.8 mm wide; style 0.5-1.5 mm long; ovary 1.2-1.7 mm with 4-5 locules. Fruit unknown.

Etymology.

The specific epithet " longkiau " means that the geographical distribution of this species is mainly distributed in Hengchun Peninsula, Pingtung County, Taiwan. The area was known as “Longkiau” in early records.

Phenology.

Flowering from February to June.

Distribution and habitat.

Aspidistra daibuensis var. longkiauensis is geographically confined to the Hengchun Peninsula, the most southern part of Taiwan and the southeastern part of Taiwan. The population typically grows on slopes under the canopies of primary or secondary forests. It is distributed at an elevation of 200-500 m.

Conservation status.

Aspidistra daibuensis var. longkiauensis is known from three populations in Hengchun Peninsula, Pingtung County, Taiwan. Based on the specimen records, the area of occupancy (AOO) is ca. 15 km2 by GeoCAT ( Bachman et al. 2011). Following the criteria of IUCN (2019), this species is assessed as endangered (EN B2ab(ii)).

Notes.

This new variety is regarded as A. daibuensis ( Chang and Hsu 1974) or A. mushaensis ( Wang 2004; Chao 2016). We determined that this species does not have thick perianth lobes as A. daibuensis var. daibuensis ( Hayata 1912). In addition, A. daibuensis var. longkiauensis differs from A. mushaensis var. mushaensis in terms of the ratio of the blade length to the blade width, perianth lobe base width, the distance from the lobe base to the stigma apex, and the ratio of the pistil length to the stamen height (Table 6 ). The stamen of this new species is inserted on the perianth tube base or near the base instead of the low part of the perianth tube, as observed in the previous former two species. We considered it can be distinguished from A. daibuensis var. daibuensis and A. mushaensis var. Aspidistra mushaensis mushaensis . However, it is morphologically more similar to A. daibuensis , so we considered regard it as a variety of A. daibuensis .

Additional specimen examined.

Taiwan. Pintung County: Kaoshifo, alt. 400 m, 14 Jun 1993, fl., T.-T. Chen et al. 1393 (TAIF!); Mt. Kaoshifo, 27 Feb 2016, fl., P.F. Lu 29262 (TAIF!); Mt. Kaoshifo, alt. 300-400 m, 16 April 2020, fl., C.T. Lu 2662 (TNU!); Shoucha, alt. 470-500 m, 17 Feb 2017, fr., S.W. Chung 12866 (TAIF!).

Figures

Figure 5. Floral comparison of Aspidistra daibuensis var. longkiauensis C. T. Lu, M. J. Yang & J. C. Wang; A. mushaensis Hayata var. mushaensis, and A. daibuensis Hayata var. daibuensis A-G A. daibuensis var. longkiauensis H-N A. mushaensis var. mushaensis O-T A. daibuensis var. daibuensis A, H, O front view of the flower B, I, P lateral view of the flower C, J, Q stigma surface D, K, R half dissection of the perianth tube, showing the pistil and stamens E, L half dissection of the perianth tube and stigma F, M, S half dissection of the perianth tube, showing the stamen G, N, T half dissection of the stigma.

Figure 6. Illustration of Aspidistra daibuensis var. longkiauensis C. T. Lu, M. J. Yang & J. C. Wang A habit B flower (front view) C flower (lateral view) D half dissection of perianth tube, showing pistil and stamens E stamen F half dissection of pistil.