Paradictyocheirospora Rajeshkumar, R. K. Verma, Boonmee, K. D. Hyde, Chandrasiri & Wijayaw., 2021

Rajeshkumar, Kunhiraman C., Verma, Rajnish K., Boonmee, Saranyaphat, Chandrasiri, Sajini, Hyde, Kevin D., Ashtekar, Nikhil, Lad, Sneha & Wijayawardene, Nalin N., 2021, Paradictyocheirospora tectonae, a novel genus in the family Dictyosporiaceae from India, Phytotaxa 509 (3), pp. 259-271 : 262-265

Paradictyocheirospora Rajeshkumar, R. K. Verma, Boonmee, K. D. Hyde, Chandrasiri & Wijayaw. gen. nov.

Index Fungorum number: IF558297; Facesoffungi number: FoF 09733

Etymology: —referring to the comparable morphological characters to that of Dictyocheirospora .

Saprobic on decaying bark. Sexual morph: Undetermined. Asexual morph: Hyphomycetous. Colonies on natural substrate, superficial. Conidiomata on natural substratum sporodochial, superficial, compact, scattered, dark brown. Mycelium immersed, septate, branched, smooth. Conidiophores micronematous, reduced to conidiogenous cells, hyaline, smooth, wider at base narrow towards tip. Conidiogenous cells monoblastic. Conidia dictyosporous, cheirosporous, non-complanate, composed of 3–6 compactly arranged rows of pale to medium brown cells with dark brown cells in upper half, basal cell hyaline, sub globose or irregular with truncate base, globose bubble-like hyaline conidial appendages present at the supra-basal part of conidia.

Type species:— Paradictyocheirospora tectonae Rajeshkumar, R. K. Verma, Boonmee, K. D. Hyde, Chandrasiri & Wijayaw.

Diagnosis: —Distinguished from other Dictyosporiaceae members based on the following key characteristics such as conidia non-complanate, composed of 3–6 compactly arranged rows of pale to medium brown cells with dark brown cells in the upper half, globose hyaline conidial appendages present at the supra-basal part of conidia.

Paradictyocheirospora tectonae Rajeshkumar, R. K. Verma, Boonmee, K. D. Hyde, Chandrasiri & Wijayaw. sp. nov. Index Fungorum number: IF 558307; Facesoffungi number: FoF 09734, Fig. 1 , 2

Etymology: —“ tectonae ” is derived from the host name Tectona grandis .

Type:— INDIA. Punjab; Chandigarh, 321 msl, 30° 45’ 38.2248’’ N and 76° 45’ 55.3968’’ E, on bark of Tectona grandis L. f. (teak) ( Lamiaceae ), 28 August 2019, Verma and Rajeshkumar, holotype – AMH 10301, ex-type culture NFCCI 4878.

Saprobic on decaying bark. Sexual morph: Undetermined. Asexual morph: Hyphomycetous. Colonies on natural substrate, superficial. Conidiomata 1–1.8 mm diam., sporodochial, superficial, compact, scattered, circular or irregular, dark brown. Mycelium , immersed, septate, branched, smooth. Conidiophores 15–25 × 1.5–3 μm, micronematous, reduced to conidiogenous cells, hyaline, smooth, wider at base narrow towards tip. Conidiogenous cells monoblastic, holoblastic. Conidia 28.5–41 × 14–17 μm, dictyocheirosporous, composed of 3–6 compactly arranged rows, pale to medium brown cells, dark brown cells in upper half, straight or slightly curved at the upper half, basal cell hyaline, subglobose or irregular with truncate base, subglobose to broadly ellipsoidal bubble-like hyaline appendages at the supra-basal part of conidia, 10–15 × 10–11.5 μm, immature conidia hyaline to pale brown, 15–18 × 10–14 μm.

Culture characteristics:— Colonies on PDA at 25 ± 2º C after 30 days slow growing, 40–60 mm diam, initially yellowish white, cinnamon brown (6D6) centre at mature with pale orange grey (6D2) towards margin, velutinous with umbonate centre, margin irregular, reverse light brown centre (6D5) to pale orange grey (6D2). Colonies on CMA at 25 ± 2º C after 30 days slow growing 40–50 mm diam, velutinous, initially white, pale orange grey (6D2) at the center with pale cinnamon-brown (6D6) towards the margin, margin irregular, reverse mustard brown (5 E 6) with yellowishwhite (4 A 2) towards margin.

Notes: A phylogenetic analysis based on a combined dataset of LSU, ITS and TEF 1α sequences show that Paradictyocheirospora formed a distinct lineage basal clade to Dictyocheirospora and Digitodesmium with low statistical support ( Fig. 3 ). Paradictyocheirospora shares similar conidial features to Dictyocheirospora and Dictyosporium in having cheiroid, digitate, with or without complanate conidia. However, Paradictyocheirospora differs from Dictyocheirospora in having sporodochial conidiomata with micronematous conidiophores, 3–6 compactly arranged rows of light to dark pigmented cells with non-complanate conidia with globose bubble-like hyaline appendages at the base ( Fig. 3 ). Therefore, Paradictyocheirospora is described as a new genus based on phylogeny and morphological comparison.

Dictyocheirospora nabanheensis Tibpromma & K.D. Hyde (2018) in Tibpromma et al., Fungal Diversity : 10.1007/ s13225-018-0408-6

Index Fungorum number: IF554474; Facesoffungi number: FoF04483

Material examined:— INDIA, Maharashtra, Thane rural area, 19° 13′ 13″ N, 72° 57′ 17″ E, ±23 msl., on Borassus flabellifer (toddy palms), 23 July 2019, Sneha Lad & Rajeshkumar KC (Specimen No. NFCCI-RKC-DS 2019); cultures, RKC-DS1 ( ITS MW 843660 , LSU MW 843779 ) and RKC-DS2 ( ITS MW 843618, LSU MW 843617) .

Saprobic on decaying leaves of Borassus flabellifer . Sexual morph not observed.Asexual morph Hyphomycetous. Conidiomata sporodochial on natural substrate in small groups, scattered, dark brown. Conidiophores micronematous, reduced to conidiogenous cell. Conidiogenous cells 9–18 × 5–7 µm, holoblastic, cylindrical, wide at the top, sometimes flat at base, dull pale brown, mostly remaining attached to the conidia. Conidia 30–40 × 18–20 µm, solitary, oval to ellipsoid, cheiroid, smooth-walled, guttulate, arranged in 6 compact rows, with 6–9 cells per row.

Note:— Morphology and DNA sequence data of ITS and LSU and phylogenetic analyses established the identity of the strain collected from India as D. nabanheensis . This is the first record of this species from India.

Figures

FIGURE 1. Paradictyocheirospora tectonae (AMH 10301, holotype) 1–4 Sporodochial conidiomata on natural substrate. 5 Colonies on PDA obverse (left) and reverse (right). 6 Colonies on CMA obverse (left) and reverse (right). Scale bars: 1 = 500 µm. 2–4 = 100 µm.

FIGURE 2. Paradictyocheirospora tectonae (AMH 10301, holotype). 1 Sporodochial conidiomata. 2 Mature conidia. 3 Young conidia. 4 Conidia with conidiophore. 5–9 Conidial variations. Scale bars: 1–9 = 10 µm.

FIGURE 3. RAxML tree based on analysis of a combined LSU, ITS and TEF1α sequence data for the family Dictyosporiaceae. Bootstrap support values for ML (left) greater than or equal to 50% are given at the nodes and hyphen (-) are marked as values below 50%. Bayesian posterior probabilities (BYPP, right) greater than or equal to 0.95 given at the nodes and hyphen (-) are marked as values below 0.95, respectively. Periconia igniaria (CBS 379.86 and CBS 845.96). The representative ex-type strains are made in bold and newly taxa are made in blue.