Lappula effusa D. H. Liu & W. J. Li, 2024

Liu, Dan-Hui, Zhou, Yi-Xin, Shang, Shu-Jing, Wu, Jia-Ju & Li, Wen-Jun, 2024, Lappula effusa (Boraginaceae), a new species from Xinjiang, China, PhytoKeys 243, pp. 105-112 : 105-112

Lappula effusa D. H. Liu & W. J. Li sp. nov.

Figs 1 , 2 , 3

Diagnosis.

The new species is morphologically similar to Lappula himalayensis and L. tadshikorum , but differs from the L. himalayensis primarily in the following characteristics: stem single (vs. stems 4–6, cespitose), erect (vs. ascending or erect), frequently branched at middle and above (vs. branched above), densely spreading hispid, hairs discoid at base (vs. densely appressed pubescent); corolla white or blue (vs. blue); fruit compressed (vs. fruit globose), nutlets acute ovoid, ca. 2.5 mm long, 1 mm wide, 0.5 mm thickness (vs. ovoid, ca. 2.5 mm long, 1.5 mm wide, 1 mm thickness), the inner glochids erect (vs. often curved), disc narrowly ovate-triangular (vs. ovoid) (Figs 2 , 3 ). Furthermore, compared to the L. tadshikorum , the new species is 12–28 cm tall (vs. 30–50 cm tall), stem single (vs. stems 2–3), densely spreading hair (vs. appressed or semi-appressed hair), fruit compressed (vs. fruit globose-ovoid), nutlets acute ovoid, 0.5 mm thickness (vs. ovoid, 1 mm thickness), disc narrowly ovate-triangular (vs. oblong or ovate), inner glochids erect, ca. 0.5 mm long (vs. curved, 1–1.2 mm long), style surpassing nutlets and glochids (vs. style slightly surpassing nutlets, but not surpassing glochids) (Figs 2 , 3 ).

Type.

China. Xinjiang: Balikun County, Dahongliuxia Village , growing on the gravel desert, 44 ° 47 ' 26.17 N, 91 ° 30 ' 9.55 E, alt. 842 m, 18 June 2023, D. H. Liu, Y. X. Zhou, S. J. Shang et al. 2023 EH 908 (holotype: XJBI 00135936 !) .

Description.

Annual herbs. Stems erect, single, frequently branched at middle and above, 12–28 cm tall, with spreading white hispid, hairs discoid at base (Fig. 3 I ). Basal leaves forming a rosette; leaf blade spatulate, 1.5–2.5 cm long, 2–4 mm wide, densely spreading white hirsute, hairs discoid at base; withered in fruit; Stem leaves linear-lanceolate, 1–2 cm long, 2–4 mm wide, abaxially densely spreading white hispid, adaxially sparsely hispid or glabrous, hairs discoid at base. Inflorescences elongated to 5–10 cm long in fruit, with oval bracts near 3–5 mm long, 1.5–2.5 mm wide. Pedicels short, ca. 1 mm long in flowering and elongated from 2.5–3 mm long in fruit. Calyx lobes oblong, ca. 1.5 mm long, 1 mm wide, slightly elongated ca. 2 mm long in fruit, spread, abaxially densely spreading hispid, adaxially sparsely hispid or glabrous. Corolla blue and white (plants with either all blue or all white corollas), campanulate, corolla tube ca. 1.5 mm long; limb as long as tube, ca. 1.5 mm wide, lobes obtuse; throat appendages white or light yellow, trapeziform, ca. 0.3 mm high; stamens five, included in the corolla tube, filament short, inserted at the middle of tube, anthers brown. Gynobase narrowly subulate (Fig. 3 J ), with a style surpassing the nutlets by ca. 0.5 mm. Coenobium laterally compressed ovoid (Fig. 3 L ), with glochids 2.5–3 mm in diameter. Nutlets four, heteromorphic, easily separated from gynobase, acute ovoid; 2.5–3 mm long, ca. 1.2 mm wide, disc narrowly ovate, adaxially granulose, centre-line keeled, with a single row glochids, glochids erect; marginal glochids in 2 rows, erect, two nutlets with the inner glochids 0.5–1 mm long, outer glochids 0.2–0.5 mm long (Fig. 3 N ); two other nutlets with short glochids, inner glochids less than 0.5 mm long, outer glochids reduced to 0.1–0.2 mm or tuberculate (Fig. 3 M ); nutlets thin, ca. 0.5 mm thickness (Fig. 3 O ); abaxially granulose, cicatrix narrow lanceolate, ca. 1 mm long, located in the base of nutlets, adaxial keel ca. 1.5 mm long (Fig. 3 P ).

Distribution and ecology.

The new species is currently known only from its type locality in Dahongliuxia Village, Balikun County, Xinjiang Province, China. It grows in gravel desert at an elevation of 840 m above sea level.

Phenology.

Flowering and fruiting from May to July.

Etymology.

The specific epithet refers to the appearance of new species, stems frequently branched at middle and above and nearly horizontal spreading.

Vernacular name.

Simplified Chinese: 展枝鹤虱 (Chinese pinyin: zhǎn zhī hè shī).

Conservation status.

Based on the current survey data, we have only found a single population of the new species at its type locality, Dahongliuxia Village, Balikun County, Xinjiang Province, China. Data for the Lappula effusa were still insufficient to assess its conservation status. According to the IUCN Criteria ( IUCN 2022), the conservation status of this new species is temporarily assessed as Data Deficient ( DD) until more information becomes available.

Notes.

Based on the classification of Lappula by Ovczinnikova (2005), the new species L. effusa should belong to the sect. Microcarpae ( M. Pop.) Ovczinnikova, ser. Tianschanicae M. Pop. ex Ovczinnikova, which is characterised by the narrowly subulate gynobase, style surpassing the nutlets by ca. 0.5–1 mm, heteromorphic nutlets with two rows of marginal glochids, disc with centre line keel. Amongst this series, there are approximately seven species ( Lappula aktaviensis Popov & Zakirov ; L. himalayensis ; L. pratensis Ching J. Wang ; L. sericata Popov ; L. subcaespitosa M Popov ex Golosk. ; L. tadshikorum ; L. tianschanica Popov & Zakirov ). L. effusa most resembles L. himalayensis and L. tadshikorum , sharing similar corolla and gynobase morphology. However, nutlets are always important for identification and classification of Lappula ( Popov 1953; Riedl 1967; Zhu et al. 1995; Ovczinnikova 2005) and the new species exhibits distinctive nutlet morphology from the compared species: i. e. relatively compressed fruit, acute ovoid nutlets, narrowly ovate disc and short marginal glochids. Additionally, L. himalayensis and L. tadshikorum are distributed in the mountain areas of Xizang and western Xinjiang (Himalaya and Pamir, usually 1800–4000 m a. s. l.), while L. effusa occurs in the gravel desert of eastern Xinjiang (lower than 1000 m a. s. l.). The detailed differences amongst these three species are provided in Table 1 .

Figures

Figure 1. Lappula effusa D. H. Liu & W. J. Li, sp. nov. A habitat B habit C, D flower morphology E inflorescences F fruit G spreading calyx in fruit.

Figure 2. Type specimens of L. himalayensis, L. tadshikorum and L. effusa A holotype of L. himalayensis (PE 00029615!) B lectotype of L. tadshikorum (LE 140!) C holotype of L. effusa (XJBI 00135936!).

Figure 3. Morphological comparisons of L. himalayensis, L. effusa and L. tadshikorum. L. himalayensis A stem indumentum B gynobase C fruit lateral view D fruit polar view E nutlet abaxial view (with short glochids) F nutlet lateral view (with long glochids) G nutlet lateral view (with short glochids) H nutlet adaxial view. L. effusa I stem indumentum J gynobase K fruit lateral view L fruit polar view M nutlet abaxial view (with short glochids) N nutlet abaxial view (with long glochids) O nutlet lateral view P nutlet adaxial view. L. tadshikorum Q stem indumentum R gynobase S fruit lateral view T fruit polar view U nutlet abaxial view (with short glochids) V nutlet abaxial view (with long glochids) W nutlet lateral view X nutlet adaxial view. Scale bar represents 0.5 mm.