Thorea baiyunensis Han, Nan & Xie, 2022

Han, Jinfen, Nan, Fangru, Feng, Jia, Lv, Junping, Liu, Qi, Liu, Xudong & Xie, Shulian, 2022, Thorea baiyunensis sp. nov. (Thoreales, Rhodophyta) and T. okadae, a new record from China, PhytoKeys 193, pp. 107-123 : 107

Thorea baiyunensis Han, Nan & Xie sp. nov.

Fig. 3I-T

Description.

Known only from the " Chantransia " sporophyte generation. Plant macroscopic, up to 25.9 mm, bluish; basal portion consisting of an irregular prostrate system of densely aggregated filaments; lateral branches developing at angle <25°. Vegetative cells of main branches cylindrical, (12.7) 13.6-63.6 (68.2) μm long and (8.2) 10.9-20.9 (22.7) μm in diameter. Monosporangia numerous, mostly grow at the tip of 1-5-celled, short branchlets, singly or in clusters, obovoidal, (11.8) 12.7-21.8 (23.6) μm long and (10.9) 11.8-16.4 (17.3) μm in diameter. Chloroplasts laminate or irregularly lobed, 2-4 per cell.

Diagnosis.

Diagnostic DNA sequence: rbc L and COI-5P (accession number: MZ648090, MZ648091, and MZ648092 for rbc L and MZ676780, MZ676781, and MZ676782 for COI-5P).

Type.

China, Guangdong Province, Baiyun Mountain, 540 m alt., 23°36.00'N, 113°49.53'E: epilithic on the rocks in spring water, November 2020, J.F. Han & K.P Fang (Holotype: SXU-SAS18040; Paratype: SXU-SAS18041). Deposited in Herbarium of Shanxi University (SXU), Shanxi University, Taiyuan, Shanxi Province , China.

Habitat and distribution.

Baiyun Mountain (23°36.00'N, 113°49.53'E), Guangdong Province, China: on the rocks in spring water; water temperature 17.3-20.6 °C, pH 6.5-7.6 (Figs 1 , 4A-C ).

Etymology.

The species epithet refers to the type locality (Baiyun Mountain, China).

Authentic strain.

SXU-GD20224.

Figures

Figure 1. Map showing approximate locations of samples investigated in this study. More detailed location information is provided in Table 1. The red circles and the green circles indicate the locations of Thorea okadae in China and Japan, respectively.

Figure 3. Morphological characters of samples investigated in this study A-D sample GX 41 A morphological observation of the tufts of erect filament, bluish in color B monosporangial branch with ovoid monosporangium (black arrow) C filament showing branch angle ≤ 25 ° (black arrow) D erect filaments arise from basal system consisting of a prostrate mass with sparse rhizoids (black arrowhead) E-H sample GX 81 E morphological observation of the tufts of erect filament, brownish in color F monosporangial branch with ovoid monosporangium (black arrow) G filament showing branch angle <25 ° (black arrow) H cells have parietal laminate or irregularly lobed Chloroplast (white arrow) I-L sample GD 224 I morphological observation of the tufts of erect filament, bluish in color J monosporangial branch with obovoidal monosporangium (black arrow) K filament showing branch angle <25 ° (black arrow) L cells have parietal laminate or irregularly lobed Chloroplast (white arrow) M-O sample GD 225 M morphological observation of the tufts of erect filament, bluish in color N monosporangial branch with obovoidal monosporangium (black arrow) O filament showing branch angle <25 ° (black arrow) P cells have parietal laminate or irregularly lobed Chloroplast (white arrow) Q-T sample GD 228 Q morphological observation of the tufts of erect filament, bluish in color R monosporangial branch with obovoidal monosporangium (black arrow) S filament showing branch angle <25 ° (black arrow) T cells have parietal laminate or irregularly lobed Chloroplast (white arrow).

Figure 4. Habitat of Thorea baiyunensis and T. okadae A-C habitat of Thorea baiyunensis D, E habitat of T. okadae.