Geopyxis carolinae Sánchez-Flores, García-Jiménez, C. Martínez-González, Ekanayaka & Raymundo, 2024

Sánchez-Flores, Marcos, García-Jiménez, Jesús, Martínez-González, César R., Ekanayaka, Anusha H. & Raymundo, Tania, 2024, Geopyxis carolinae sp. nov. (Pezizomycetes, Ascomycota) from Mexico, Phytotaxa 655 (3), pp. 221-230 : 224-226

Geopyxis carolinae Sánchez-Flores, García-Jiménez, C. Martínez-González, Ekanayaka & Raymundo sp. nov. ( Figures 2–3 )

Mycobank no. MB 842941

Etymology: dedicated to D. Carolina González-Sánchez, who collected the species for the first time.

Type: MEXICO,State of Mexico, Texcoco Municipality,CanoasAltas, Mount Tlaloc , 19°24'43.82"N, 98°44'58.86" W, 3559 m a. s. l., 06 July 2020, D. C. González-Sánchez 01 (holotype: ITCV! [DCGONZÁLEZSÁNCHEZ-01- ITCV]) .

Diagnosis: Geopyxis carolinae differs from the other species by having asci sizes of 260–310 × 12–14 (15) µm and the largest ascospores of 17–23 (25) × 10–12 µm within the genus.

Description: Sexual morph: Ascomata apothecial. Apothecia 3–11 mm diameter [= 7.2 mm, n= 24], cupuliform when young to discoid at maturity stage, solitary to gregarious, sessile to subsessile, with a stipe up to 1. 5 mm high, greyish orange (5B4) to melon (5A7), entire margin to slightly lobed, crenulate, dentate to serrate, cracking at maturity, white colour at the beginning and becoming light brown (6D6) at maturity stage, the exterior of apothecium concolorous smooth to finely pruinose, at base forming folds that unite with a stipe, smooth hymenium. Ectal exciple 65–125 µm thick, consisting of cells 15–25 × 10–17 µm, angular to subglobose in texture, subhyaline, thin wall 1–1. 5 µm wide. Medullary exciple 60–133 µm thick, formed by hyphae 3–5 µm, intricate texture, subhyaline. Subhymenium 25–50 µm thick. Hymenium 260–328 µm thick. Paraphyses 2–3 µm diameter, filiform, hyaline, septate, sparsely branched. Asci 260–310 × 12–14 (15) µm [= 284 × 12.8 µm, n = 20], cylindrical, clavate, octospored, inamyloid. Ascospores 17–23 (25) × 10–12 µm [= 19. 9 × 11.1 µm, n = 74], Q = 1.5-2 (2.3), Qm = 1.7, elliptical to oblong-elliptical, hyaline, smooth, multigutulate. Asexual morph: Unknown.

Distribution: Known from the type locality, State of Mexico, Mexico.

Notes: Geopyxis carolinae is characterized by greyish orange to orange apothecia up to 11 mm in diameter, cylindrical and inamyloid asci, and elliptical to oblong-elliptical, smooth ascospores of 17–23 (25) × 10–12 µm. Phylogenetically, it is closely related to G. rehmii Turnau ; however, it has verrucous and smaller ascospores 10–19 × 9–10 µm (Turnau 1985). Another related species is G. carbonaria (Alb. & Schwein) Sacc. , which differs from G. carolinae by its smaller ascospores 12–18 × 6.5–11 µm, like G. korfii W. Y. Zhuang 12–15 × 8–10 µm. Conversely, the ascospores of both species have a verrucous wall ( Wang et al. 2016, Zhuang and Liu 2006), but the ascospores of G. carolinae are smooth ( Table 3 ).

Additional specimens examined: MEXICO. State of Mexico, Municipality of Texcoco, Mount Tlaloc 19°24’43.82” N, 98°44’58.86” W, 3559 m a. s. l., 14 November 2021, D.C. González-Sánchez 02 (Paratype: ENCB), M. Sánchez 2573 (ITCV), 2575 (ITCV), 2580 (ITCV), 2582 (ITCV), 2591 (ITCV), 2602 (ITCV), 2605 (ITCV), 2608 (ITCV), 2612 (ITCV), 2615 (ITCV), and 2620 (ITCV). Loc. cit., 16 January 2022, M. Sánchez 2687 (ITCV) and 2690 (ITCV). Loc. cit., 18 September 2020, M. Sánchez 2981 (ITCV). Loc. cit., 21 September 2022, M. Sánchez 2995 (ITCV). Loc. cit., 25 September 2022, M. Sánchez 3040 (ITCV) and 3049 (ITCV).

Figures

FIGURE 2. Geopyxis carolinae (Holotype: DCGONZÁLEZSÁNCHEZ-01-ITCV). A, B. Gregarious apothecia. C. Mature apothecia. D, E. Young apothecia.

FIGURE 3. Geopyxis carolinae (Holotype: DCGONZÁLEZSÁNCHEZ-01-ITCV). A. Longitudinal section of the apothecium. B. Ectal excipulum. C. Paraphyses. D. Asci. E. Ascospores in 5% KOH.