Bisifusarium cacticola K. Zhang & Crous, 2025

Zhang, K., Sandoval-Denis, M., Kandemir, H., Yilmaz, N., Groenewald, J. Z., Yáñez-Morales, M. de J., Wingfield, M. J. & Crous, P. W., 2025, Taxonomic revision of Bisifusarium (Nectriaceae), Persoonia 54 (1), pp. 197-223 : 208

Bisifusarium cacticola K. Zhang & Crous , sp. nov. MB 858739 . Fig. 5.

Etymology: Name refers to the cactus host from which this fungus was isolated.

Sporodochia greyish orange, formed abundantly on CLA. Sporodochial conidiophores verticillately branched and densely packed; sporodochial phialides subulate to subcylindrical, 15–35 × 3–4 µm, smooth- and thin-walled. Sporodochial macroconidia slender, falcate, slightly curved with almost parallel sides tapering slightly towards both ends, with a papillate to hooked, curved apical cell and a blunt to rarely poorly developed foot-like basal cell, 1(–2)-septate, hyaline, smooth- and thin-walled, (14.6–)16.3–19.0(–21.1) × (2.4–)2.7–3.0(–3.5) µm. Chlamydospores intercalary, solitary or in short chains, globose to ellipsoid, hyaline becoming pale reddish brown, 5–8 µm diam.

Culture characteristics: Colonies in the dark for 7 d at 25 °C: on OA grown in the dark, reaching 7–8 cm diam., pale brown. Colonies on PDA reaching 7–8 cm diam., raised, aerial mycelium dense, colony margin erose, surface and reverse red. Colonies on SNA reaching 2.5–3.5 cm diam., flat, aerial mycelium scant, colony margin filamentous, snowflake-like embedded in agar, nearly transparent, with chestnut pigmentation.

Typus: Italy, from Opuntia ficus-indica , collection date unknown, G. Granata (holotype CBS H-25450 , culture ex-type CBS 101615 ).

Additional materials examined: South Africa, Limpopo Province, Mokopane , from dry rot of Opuntia ficus-indica cv. Zastron, Mar. 2013, W.J. Swart, cultures CBS 153382 = CPC 22100 , CBS 153383 = CPC 22120 ; Limpopo Province, Nebo , dry rot of Opuntia ficus-indica cv. Morado, Mar. 2013, W.J. Swart, culture CBS 153384 = CPC 22132 . USA, Washington, human sinus, collection date and collector unknown, culture CBS 110312 = CBS 116525 = FRC E-0306 = NRRL 34031 = NRRL 36185 .

Note: Originally assigned to Fusarium sp. 5 by Schroers et al. (2009), B. cacticola is closely related to B. lunatum but can be distinguished from that species by its growth on PDA at 25 °C for 7 d, reaching 7–8 cm diam. in B. cacticola , and 4–4.5 cm diam. in B. lunatum . Furthermore, B. cacticola produces greyish orange sporodochia on CLA ( Schroers et al. 2009), while B. lunatum has hyaline sporodochia on the same substrate. Additionally, both species differ by 56 bp in the combined alignment (ITS 1, rpb2 21, tef1 22, and tub2 12 bp).