Pseudosclerococcum golindoi

Pseudosclerococcum golindoi Olariaga, Teres, J.M. Martín, M. Prieto & Baral, Mycol. Progress 18: 898. 2019. [pdf]

MycoBank MB829827

AUTHORS: Olariaga I., Teres J., Martín J.

 

Taxonomic classification

phy Ascomycota

sbp Pezizomycotina

cls Eurotiomycetes

sbc Sclerococcomycetidae

ord Sclerococcales

fam Sclerococcaceae

gen Pseudosclerococcum

sp golindoi

Description

Apothecia scattered or densely gregarious, subsessile or sessile, black, shiny, initially cup-shaped, then plane and finally pulvinate, rarely umbilicate in the centre, 1.5–3.5 mm diam. Margin slightly to strongly raised and distinct in young ascomata, obtuse, regular, finely rough. Stipe sometimes present, black, glabrous, 0–0.5 × 0.4– 0.5 mm. Apothecial outside black, dull. Epithecium formed by dark-reddish brown exudates around paraphysis heads, pigmentation amorphous-resinous, sometimes rather indistinct, not dissolved in KOH. Hymenium below terminal cells, hyaline to pale reddish brown, 120–150 μm thick. Paraphyses distantly septate, slightly constricted at septa at the lower part, unbranched, 2–2.5 μm diam, apical cells usually with pale reddish brown exudate, claviform, 3–4 μm diam., without visible cytoplasmic contents, IKI–. Asci cylindrical, slightly thick-walled in the upper part (dead state), developing a †3–8 μm thick apical wall thickening (tholus) during ascus maturation; tholus compressed in living asci, sometimes with a pore-like structure, bitunicate, fissitunicate, with endotunica strongly elongating during discharge, with a basal crozier, 8-spored, *120–141 × 8–10.5 μm, †6–7.5 μm wide, lateral walls †1–2 μm thick, IKI–, KOH/IKI–, hyaline; congophobous gelatin covering the ascus wall hemiamyloid (IKI red, type RR, KOH/IKI blue). Ascospores ellipsoid to slightly obovate, rarely slightly curved, homopolar or somewhat heteropolar, thin-walled, 1-septate, hyaline to very pale brown inside living asci, brown when overmature, *with a large guttule and several smaller ones per cell, †with a large guttule per cell, spore wall covered with hemisphaerical warts, 0.3–0.5 μm high, *(9–)10–12(−13.5) × (4–)4.5–5.5(−6) μm (Lm = 10.3–11.9, Wm = 4.9–5.3, Qm = 2.1–2.3), †(8–)9–12 × 4–5 μm (Lm = 10–10.3, Wm = 4.6–4.7, Qm = 2.2), obliquely uniseriate in the ascus. Subhymenium of dense, dark reddish brown, textura intricata. Medullary excipulum dark reddish brown to black-brown, 130–500 μm thick, composed of two sharply delimited zones: a) inner part composed of subglobose to cylindrical, thick-walled cells surrounded by a dark reddish brown matter, 1.5–3 μm broad, forming a dense textura intricata and b) outer part composed of subglobose to polygonal or elongated, slightly thick-walled cells with dark reddish brown pigment at septum edges, 12–33 × 10–15 μm, forming a textura angularis. Ectal excipulum bright reddish-brown, 120–350 μm thick, with isodiametric to elongated, polygonal cells, arranged in vertical, vaguely parallel rows, slightly thick-walled, with dark reddish brown pigment at septum edges, 15–45 × 8–27 μm, forming a textura angularis. Outermost cells covered with an amorphous, almost crystalloid matter, dark reddish brown. Anchoring hyphae sometimes present near the apothecial base, sparse, brown, encrusted, septate, thick-walled, 2–3.5 μm thick. Apothecial sections losing reddish colour by turning dull brown in KOH, not releasing dissolved pigment into the medium. Asexual morph observed in culture. Colonies on MEA 10– 15 mm diam in 60 days at 20 °C, superficial, effuse, convex, hairy, glaucous green, sometimes whitish in the centre. Reverse blackish green. Margin regular and distinct. Vegetative hyphae cylindrical, septate, pale greenish brown to dark brown, smooth, sometimes covered with dark brown resinous exudates, 2.5–4 μm broad. Conidiophores scattered, simple, brown, erect, straight, rarely with a sinuous wall, cylindrical, septate, smooth, sometimes with brown resinous exudates, thin-walled to slightly thick-walled, 59–132 × 3–5.5 μm. Conidia in short chains, ellipsoid to shortly clavate, truncate at the basal end with minute inconspicuous marginal frill, non-septate, thin-walled, smooth, pale brown, with a few inconspicuous minute guttules, *6.5–8(−8.5) × 3–4(−4.5) μm (Lm = 7.5, Wm = 3.7, Qm = 2).

Habitat, distribution and comments: This species was named after the recently deceased mycologist José Luis Albizu Mayoz, so-called “Golindo”. Pseudosclerococcum golindoi is distinguished from species of Sclerococcum (=Dactylospora) in having cylindrical, entirely hemiamyloid asci, opposed to the asci with an amyloid gelatinous cap in Sclerococcum (=Dactylospora). It occurs on fallen and decorticated logs of angiosperms (Platanus, Ulmus), highly decayed, lying on the ground, fruiting on the upper side or on the underside of the log. Found in the vicinity of Ascocoryne cylichnium (Tul.) Korf., twice. In the the log in which the holotype was collected Tomentella crinalis and Armillaria rhizomorphs were also found. Both localities from where P. golindoi is known are narrow ravines along streams, with well-preserved riparian forests with ecological continuity and abundant dead wood. Due the mild oceanic climate with abundant precipitation, both sites host several ferns, bryophytes and lichens of tropical affinity and considered tertiary relicts, such as Dumortiera hirsuta, Hookeria lucens, Osmunda regalis, Stegnogramma pozoi, Sticta canariensis, Vandenboschia speciosa or Woodwardia radicans. Although it is premature to predict its distribution, we think it is plausible to find it other sites along the Cantabrian sea, and probably in Macaronesia, rather than further north in Europe. Esp: SS.

 

References in our territory
  • Olariaga I, Teres JL, Martín J, Prieto M. & Baral HO. 2019. Pseudosclerococcum golindoi gen. et sp. nov., a new taxon with apothecial ascomata and a Chalara-like anamorph within the Sclerococcales (Eurotiomycetes). Mycol. Progress 18: 898. (Esp: SS) [pdf]

 

Specimens in scientific collections

* sequenced material

Reference specimen marked in bold

Spain

SS: ARAN-Fungi 6619* (holotypus, dupla in UPS; ex-type culture CBS 143732), ARAN-Fungi 6618, ARAN-Fungi 265, ARAN-Fungi 11726

 

Sequences in public databases obtained from material collected in our territory

ARAN-Fungi 6619: NG_073673 (LSU), NR_171236 (ITS), NG_070882 (SSU), MK759897 (mtSSU),

 

Riparious forest in Mindi erreka (Aia, Gipuzkoa, Pagoeta Natural Park). Site where the holotypus was collected. Photograph J. Teres.

Riparious forest in Mindi erreka (Aia, Gipuzkoa, Pagoeta Natural Park). Site where the holotypus was collected. Photograph J. Teres.

Pseudosclerococcum golindoi. In situ apothecia on the same log as the holotype collection. Photograph J. Teres.

Pseudosclerococcum golindoi. In situ apothecia on the same log as the holotype collection, co-occurring with Ascocoryne cylichnium. Photograph J. Teres.

Pseudosclerococcum golindoi. In situ apothecia on the same log as the holotype collection, co-occurring with Ascocoryne cylichnium. Photograph J. Teres.

Pseudosclerococcum golindoi. In situ apothecia on the same log as the holotype collection. Photograph J. Teres.

Pseudosclerococcum golindoi. Living ascospores from an apothecium collected on the same log as the holotype. Photograph J. Martín.

Living asci containing ascospores, from the holotype collection (ARAN-Fungi 6619). Photograph I. Olariaga.

Ascal development in P. golindoi (mostly from ARAN-Fungi 6619, holotype). a) Young living ascus, b) living ascus with a slightly thick-walled apex, containing submature ascospores with incipient ornamentation, c) living ascus with a pore-like structure at the apex containing mature ascospores with clear ornamentation, d) dead empty asci in which the endotunica has extruded out of the ectotunica, e) dead ascus in IKI showing a red (hemiamyloid) reaction of the surrounding gelatin, f dead ascus in KOH/IKI showing a blue reaction induced by KOH-pretreatment, g) dead submature ascus with a thickwalled tholus, containing immature ascospores still without ornamentation, h) dead submature ascus with a thick-walled tholus showing a subapical constriction with ascoplasm extension, i) ascus base. Scale bars = 10 μm. Photographs I. Olariaga

Paraphyses in water (ARAN-Fungi 6619, holotype). Scale bar 10 µm.

Apothecial section in water (ARAN-Fungi 6619, holotype). Scale bar 50 µm. Photograph I. Olariaga.

Cultural characters of P. golindoi (culture ex type, CBS 143732), a) Culture in MEA, b) Chalara-like asexual morph, c) Hyphae, d) Conidia. Scale bars 10 µm. Photographs I. Olariaga.

 

How to cite this sheet:

Olariaga I., Teres J.L. & Martín J. 2021. Pseudosclerococcum golindoi Olariaga, Teres, J.M. Martín, M. Prieto & Baral. Fichas SIM 35. (updated on 27-IV-2021). Available at: https://micologiaiberica.org/en/services/pseudosclerococcum-golindoi