Anteaglonium saxicola N. Suwannarach & J. Kumla, 2023

Suwannarach, Nakarin, Kumla, Jaturong, Khuna, Surapong, Thitla, Tanapol, Senwanna, Chanokned, Hongsanan, Sinang & Lumyong, Saisamorn, 2023, Anteaglonium saxicola (Anteagloniaceae, Pleosporales), a new species isolated from rocks in northern Thailand, Phytotaxa 629 (1), pp. 75-84 : 79-81

Anteaglonium saxicola N. Suwannarach & J. Kumla sp. nov. FIGURE 2

MycoBank number: MB850037

Etymology:— ‘ saxicola ’ refers to a stone inhabitant.

Type:— THAILAND, Lamphun Province, Mueang Lamphun District, Sribuaban Subdistrict , Chiang Mai University Hariphunchai Campus , 18°32′11′′N, 99°07′30′′ E, isolated from a rock of a natural forest, 15 November 2022, N. Suwannarach, SDBR-CMU481 , a dried cultured on PDA, culture ex-type SDBR-CMU481, preserved in a metabolically inactive state .

Description:—Isolated from rock in terrestrial habitat. Sporulation on PDA after incubation at 25°C for two months. Conidiomata were observed under a stereo microscope, 70–175 µm high, 60–145 µm diam., pycnidial, globose to subglobose, scattered or aggregated into clusters, immersed to erumpent, dark brown to black, ostiolate, covered with white mycelia. Conidiomata wall 8–44 µm wide, composed of thick-walled cells of textura angularis, brown to dark brown. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 8–19 × 2–6 µm, hyaline, smooth, ampulliform to subcylindrical, arising from the inner cavity of the conidioma wall. Conidia 3–4 × 2–3 µm, hyaline, solitary, subglobose to broadly ellipsoid, aseptate, smooth-walled.

Culture characteristics:—Colonies on PDA reaching 32–35 mm diam. after 4 weeks at 25°C, flattened, wrinkled, with entire edges; colony from above, greyish-white at the center, greyish red at the margin, produced a soluble red pigment; from below: greyish ruby at the center, dark ruby at the margin. Colonies on MEA reaching 23–26 mm diam. after 4 weeks at 25°C, flattened, with entire edges, slightly concentric ring in the middle; colony from above, greyish-white; from below: brown, with white at the margin, dark grey in the middle, radiated with concentric sectors, producing light brown pigmentation around the colony. Colonies on CMD reaching 32–35 mm diam. after 4 weeks at 25°C, flattened, with entire edges, concentric ring; colony from above, light brown in the center, yellowish-white at the margin; from below: light brown in the middle, with white to cream at the margin, strongly radiated with concentric sectors, producing light brown pigmentation around the colony.

Additional specimen examined:— THAILAND, Lamphun Province, Mueang Lamphun District, Sribuaban Subdistrict, Chiang Mai University Hariphunchai Campus, 18°32′11′′N, 99°07′30′′ E, isolated from a rock of a natural forest, 15 November 2022, N. Suwannarach, SDBR-CMU482, a dried cultured on PDA, living culture SDBR-CMU482.

Notes:—Morphologically, the new species fitted well with the asexual morph of the genus Anteaglonium . The growth of A. saxicola at 25°C on MEA was slower than A. parvulum and A. thailandicum (13–16 and 23 mm, respectively, after incubation for 7 d) ( Jayasiri et al. 2016), while it displayed faster growth than A. rubescens (11–13 mm after incubation for 2 months) ( Jaklitsch et al. 2018). Remarkedly, A. saxicola displayed faster growth than A. rubescens on PDA and CMD (10 and 5–6 mm, respectively) after incubation at 25°C for four weeks. Based on the asexual morph characteristics, A. saxicola differs from A. parvulum , A. rubescens , and A. thailandicum by its longer conidiogenous cells ( TABLE 2 ) ( Jayasiri et al. 2016, Jaklitsch et al. 2018). Moreover, A. saxicola can be distinguished from A. rubescens by its wider conidiomata wall ( Jaklitsch et al. 2018). However, due to the indeterminate morphological characteristics of the asexual morphs of A. abbreviatum , A. brasiliense , A. globosum , A. gordoniae , A. latirostrum , A. lusitanicum , and A. queenslandicum , we cannot compare their microscopic structures ( Mugambi & Huhndorf 2009, Almeida et al. 2014, Jayasiri et al. 2019, Tan et al. 2022, Tan & Shivas 2023).

Phylogenetically, Anteaglonium saxicola is closely related to A. lusitanicum and A. parvulum ; however, the genetic distance of the nrLSU and ITS sequences of A. saxicola to A. lusitanicum was 0.93 and 5.5% (8/867 and 27/491 bp including gaps), respectively. Furthermore, the genetic distance of nrLSU and ITS sequences also indicated that A. saxicola differs from A. parvulum MFLUCC 10-0928, MFLUCC 11-0511, MFLUCC 11-0374, and MFLUCC 11-0380 by having 1.35% and 6.97% (11/817 and 34/488 bp including gaps), 1.24% and 5.92% (10/805 and 29/490 bp including gaps), 1.24% and 6.31% (10/804 and 31/491 bp include gaps), and 1.49% and 6.12% (12/804 and 30/490 bp including gaps), respectively.

Figures

FIGURE 2. Anteaglonium saxicola (SDBR-CMU481, ex-type). Colonies incubated at 25°C for four weeks. a. PDA. b. MEA. c. CMD (left, surface view and right, reverse view). d, e. Conidiomata forming on PDA after incubation at 25°C for two months. f. Vertical section of conidiomata. g. Conidiomata wall. h. Conidiogenous cells. i. Conidia. Scale bars: a–c = 10 mm, d = 500 µm, e, f = 100 µm, g–i = 10 µm.