Tetraploa maritima R. Asghari, Phukhams. & K. D. Hyde, 2025

Asghari, Raheleh, Phukhamsakda, Chayanard, Jones, E. B. Gareth, Bahkali, Ali, Apurillo, Carlo Chris S., Karimi, Omid, Kakumyan, Pattana & Hyde, Kevin D., 2025, Morphology and phylogeny reveal two new species and host records of hyphomycetous fungi on Areca species from marine habitats in Thailand, MycoKeys 118, pp. 179-206 : 179-206

Tetraploa maritima R. Asghari, Phukhams. & K. D. Hyde sp. nov.

Etymology.

The epithet “ maritima ” refers to the marine habitat where the holotype was collected.

Holotype.

MFLU 24-0455 .

Description.

Saprobic on decaying branches of Areca sp. Sexual morph: Undetermined. Asexual morph: Hyphomycetous (in vivo, Fig. 5 ). Mycelia on natural substrates superficial, branched, septate, sometimes with swollen cells, black or dark brown. Conidiophores not observed. Conidiogenous cells 4.5-17 × 1-3 µm (x – = 11 × 2 μm, n = 5) monoblastic, brown, thick walled, integrated. Conidia 14-28 × 13-18.5 µm (x – = 21.5 × 15 μm, n = 20), solitary, short cylindrical, thick-walled, verrucose to granular, brown, mostly with a subhyaline to pale brown hilum up to 13 µm (– 17), with 3–4 columns 5.5-9 µm wide (x – = 7, n = 20), columns are compact and connected almost all their length, 2–4 septa in each column, constricted at septa. Appendages 19-48 × 2-3 µm (x – = 30 × 2.7 μm, n = 15), 3.5-4.5 µm at the base, setose, unbranched, thick-walled, thin-walled at the apex, up to four septa, finely verrucose, brown, pale brown to subhyaline at the apex, sometimes continuing to grow, forming a subcylindrical narrower paler cell up to 13 µm (n = 10) length.

Culture characteristics.

Conidia germinating on PDA within 12 h. Colonies on PDA reaching 1.5 cm diam. after 10 d at 25 ± 2 ° C, velvety to floccose, raised, round, entire margin, grayish yellow, with whitish edge, reverse reddish brown with pale buff edge.

Material examined.

Thailand, Prachuap Khiri Khan Province, Pranburi , on decaying Areca wood submerged in seawater and trapped between rocks, 25 October 2022, K. D. Hyde, R 6 g ( MFLU 24-0455 , holotype), ex-type living culture ( MFLUCC 24-0565 ) .

GenBank numbers.

Tetraploa maritima MFLUCC 24-0565 (ex-type): ITS = PQ 778934, LSU = PQ 778930, SSU = PQ 778940, tub 2 = PQ 885482.

Notes.

The reconstruction of phylogenies from LSU, ITS, tub 2 and SSU sequence data showed that Tetraploa maritima ( MFLUCC 24-0565 ) formed a distinct clade with T. pseudoaristata ( NFCCI 4624 , NFCCI 4625 , NFCCI 4626 ) in both maximum likelihood and Bayesian analyses with 95 % ML / 0.94 BPP statistical support. Both maximum likelihood and Bayesian analyses showed the same topology. The closest match of the ITS sequence of Tetraploa maritima ( MFLUCC 24-0565 ) was 98.92 % similar across 100 % of the query sequence to T. pseudoaristata ( NFCCI 4626 ). In a BLAST search in GenBank, the closest match of the LSU sequence of T. maritima ( MFLUCC 24-0565 ) was 99.88 % similar to T. pseudoaristata ( NFCCI 4624 , NFCCI 4625 , NFCCI 4626 ). Tetraploa maritima ( MFLU 24-0455 ) has similar morphology to T. pseudoaristata ( NFCCI 4624 ) by having verrucose conidia with four apical appendages but differs in having a distinguishable hilum and shorter and narrower appendages (19-48 × 2-3 µm vs. 23–107.5 × 2.4–5.2 µm), which are sometimes elongate above the apex, unlike T. pseudoaristata ( NFCCI 4624 ). Conidial columns in T. maritima ( MFLU 24-0455 ) are compact and connected almost fully along the length, while in T. pseudoaristata ( NFCCI 4624 ) they are partly split, with the two columns totally separating at the upper part ( Hyde et al. 2020). Tetraploa maritima ( MFLUCC 24-0565 ) showed 2.7 % (16 out of 595), 0.2 % (2 out of 874) and 2.4 % (10 out of 423) base pair differences with T. pseudoaristata ( NFCCI 4624 ) in ITS, LSU and tub 2 respectively, without gaps. Therefore, T. maritima ( MFLU 24-0455 ) is introduced as a novel species based on morphological and molecular evidence.

Figures

Figure 5. Tetraploa maritima (MFLU 24-0455, holotype) a colonies on the host substrate b close - up of colonies c conidiogenous cell and conidium d – j conidia (arrows show the ongoing growth of appendages) k colony on PDA after 10 days (above) l colony on PDA after 10 days (reverse). Scale bares: 100 µm (b); 10 µm (c – f); 20 µm (g – j).