Research Article |
Corresponding author: Valeria Prigione ( valeria.prigione@unito.it ) Academic editor: Marc Stadler
© 2019 Anna Poli, Elena Bovio, Gerard Verkley, Valeria Prigione, Giovanna Cristina Varese.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Poli A, Bovio E, Verkley G, Prigione V, Varese GC (2019) Elbamycella rosea gen. et sp. nov. (Juncigenaceae, Torpedosporales) isolated from the Mediterranean Sea. MycoKeys 55: 15-28. https://doi.org/10.3897/mycokeys.55.35522
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Elbamycella rosea sp. nov., introduced in the new genus Elbamycella, was collected in the Mediterranean Sea in association with the seagrass Posidonia oceanica and with the brown alga Padina pavonica. The affiliation of the new taxon to the family Juncigenaceae is supported by both morphology and phylogenetic inference based on a combined nrSSU and nrLSU sequence dataset. Maximum-likelihood and Bayesian phylogeny proved Elbamycella gen. nov. as a distinct genus within Juncigenaceae. The new genus has been compared with closely related genera and is characterised by a unique suite of characters, such as ascospores with polar appendages and peculiar shape and dimension of ascomata and asci.
Marine fungi, new taxon, TBM clade
Marine fungi are a considerable part of the huge diversity of microorganisms that inhabit the Oceans (
The number of marine fungi has been estimated to exceed 10,000 taxa, but the most recent update in marine mycology listed only 1,206 species belonging to Ascomycota, Basidiomycota, Chytridiomycota, and Mucoromycota. Thus fungal diversity is largely undescribed (
In an attempt to clarify the phylogeny of the genera Swampomyces Kohlm. & Volkm.-Kohlm. and Torpedospora Meyers,
Recently, during a survey focused on the fungal diversity in the Mediterranean Sea, two unidentified Sordariomycetes were isolated from the seagrass Posidonia oceanica (L.) Delile (
The fungal isolates investigated in this paper were previously retrieved from P. oceanica (MUT 4937 = CBS 130520) and P. pavonica (MUT 5443) from the coastal waters of Elba island, in the Mediterranean Sea (
Dataset used for phylogenetic analysis. Genbank sequences including newly generated ITS, LSU and SSU amplicons relative to Elbamycella rosea sp. nov. and Torpedospora ambispinosa MUT 3537.
Species | Strain Code | Source | ITS | SSU | LSU |
---|---|---|---|---|---|
HYPOCREALES | |||||
Bionectria pityrodes (Mont.) Schroers | GJS95-26 | Bark | – | AY489696 | AY489728 |
Clonostachys rosea (Link.) Schroers | GJS90-227 | Bark | – | AY489684 | AY489716 |
Cordyceps militaris (L.) Fr. | NRRL 28021 | – | – | AF049146 | AF327374 |
Fusarium solani (Mart.) Sacc. | GJS89-70 | Bark | – | AY489697 | AY489729 |
Trichoderma deliquescens (Sopp.) Jaklitsch | ATCC 208838 | Pine wood | – | AF543768 | AF543791 |
MICROASCALES | |||||
Cephalotrichum stemonitis (Pers.) Nees | AFTOL 1380 | Seed | – | DQ836901 | DQ836907 |
Halosphaeria appendiculata Linder | NTOU4004 | Driftwood | – | KX686781 | KX686782 |
Lignincola laevis Hohnk | JK5180A | Wooden stake | – | U46873 | U46890 |
Microascus trigonosporus Emmons & Dodge | AFTOL 914 | – | – | DQ471006 | DQ470958 |
Nimbospora effusa Kock | NTOU4018 | Intertidal wood | – | KX686793 | KX686794 |
Nohea umiumi Kohlm. & Volkm. Kohlm. | NTOU4006 | Driftwood | – | KX686795 | KX686796 |
Petriella setifera (Schmidt) Curzi | AFTOL 956 | Wood panel in coastal water | – | DQ471020 | DQ470969 |
TORPEDOSPORALES | |||||
Etheirophoraceae | |||||
Etheirophora blepharospora (Kohlm. & E. Kohlm.) Kohlm. & Volkm. Kohlm. | JK5397A | Bark on submerged proproots | – | EF027717 | EF027723 |
E. unijubata Kohlm. & Volkm. Kohlm. | JK5443B | Submerged wood | – | EF027718 | EF027725 |
Swampomyces armeniacus Kohlm. & Volkm. Kohlm. | JK5059C | Mangroves | – | EF027721 | EF027728 |
S. triseptatus Hyde & Nakagiri | CY2802 | Submerged wood | – | AY858942 | AY858953 |
Juncigenaceae | |||||
Juncigena adarca Kohlm., Volkm. Kohlm. & Erikss | JK5548A | Juncus roemerianus | – | EF027720 | EF027727 |
J. fruticosae (Abdel-Wahab, Abdel-Aziz & Nagah.) Mill. & Shearer | EF14 | Driftwood | – | GU252146 | GU252145 |
IMI391650 | Driftwood | – | NG_061097 | NG_060791 | |
Khaleijomyces marinus Abdel-Wahab | MD1348 | Driftwood | – | MG717679 | MG717678 |
Marinokulati chaetosa (Kohlm.) Jones & Panf | BCRC FU30271 | Driftwood | – | KJ866929 | KJ866931 |
BCRC FU30272 | Driftwood | – | KJ866930 | KJ866932 | |
Fulvocentrum aegyptiacum (Abdel-Wahab, El-Shar. & Jones) Jones & Abdel-Wahab | CY2973 | Mangroves | – | AY858943 | AY858950 |
F. clavatisporum (Abdel-Wahab, El-Shar. & Jones) Jones & Abdel-Wahab | LP83 | Mangroves | – | AY858945 | AY858952 |
Elbamycella rosea sp. nov. | MUT 4937 | P. oceanica | MK775496* | MK775501* | MK775499* |
Elbamycella rosea sp. nov. | MUT 5443 | P. pavonica | MK775497* | MK775502* | MK775500* |
Torpedosporaceae | |||||
Torpedospora ambispinosa Kohlm. | CY3386 | Driftwood | – | AY858941 | AY858946 |
BCC16003 | Driftwood | – | AY858940 | AY858949 | |
MUT 3537 | Driftwood | MK775503* | MK775498* | MK775495* | |
T. mangrovei (Abdel-Wahab & Nagah.) Jones & Abdel-Wahab | NBRC 105264 | Mangroves | NR_138418 | GU252150 | GU252149 |
T. radiata Meyers | BCC11269 | Driftwood | – | AY858938 | AY858948 |
PP7763 | Driftwood | – | AY858939 | AY858947 | |
FALCOCLADIALES | |||||
Falcocladiaceae | |||||
Falcocladium multivesiculatum Silveira, Alfenas, Crous & Wingf | CBS 120386 | Leaves | – | JF831928 | JF831932 |
F. sphaeropedunculatum Crous & Alfenas | CBS 111292 | Leaves | – | JF831929 | JF831933 |
F. thailandicum Crous & Himaman | CBS 121717 | Leaves | – | JF831930 | JF831934 |
F. turbinatum Somrith., Sudhom, Tippawan & Jones | BCC22055 | Dead leaves | – | JF831931 | JF831935 |
XYLARIALES | |||||
Daldinia concentrica (Bolton) Ces. & De Not. | ATCC 36659 | Fraxinus sp. | – | U32402 | U47828 |
Hypoxylon fragiforme (Pers.) Kickx | HKUCC 1022 | Bark | – | AY083810 | AY083829 |
Xylaria hypoxylon (L.) Grev. | AFTOL 51 | Rotting wood | – | AY544692 | AY544648 |
MUT 4937 and MUT 5443 were pre-grown on CMA-sea water (CMASW; 17 g corn meal agar in 1 L of sea water) for one month at 21 °C prior to inoculation in triplicate onto Petri dishes (9 cm Ø) containing CMASS, CMASW, Potato Dextrose Agar (PDA) SS or PDASW. Petri dishes were incubated at 10 °C and 21 °C. The colony growth, together with macroscopic and microscopic traits, were monitored for 28 days.
Reproductive structures were observed and captured using an optical microscope (Leica DM4500B, Leica microsystems GmbH, Germany) equipped with a camera (Leica DFC320, Leica microsystems GmbH, Germany). Macro- and microscopic features were compared with the available description of Juncigenaceae (
Genomic DNA was extracted from about 100 mg of mycelium carefully scraped from CMASS plates. Mycelium was transferred to a 2 mL Eppendorf tubes and disrupted in a MM400 tissue lyzer (Retsch GmbH, Haan, Germany). Extraction was accomplished using a NucleoSpin kit (Macherey Nagel GmbH, Duren, DE, USA) following the manufacturer’s instructions. The quality and quantity of DNA samples were measured spectrophotometrically with Infinite 200 PRO NanoQuant (TECAN, Switzerland) and stored at −20 °C.
The primer pairs ITS1/ITS4 (
A dataset consisting of nrLSU and nrSSU was assembled on the basis of BLASTn results and of a recent phylogenetic study focused on Torpedosporales (
Phylogenetic inference was estimated using both Maximum Likehood (ML) and Bayesian Inference (BI). The ML analysis was performed using RAxML v. 8.1.2 (
Sequence alignments and phylogenetic tree were deposited in TreeBASE (http://www.treebase.org, submission number 24426).
Preliminary analyses were carried out individually with nrSSU and nrLSU. The topology of the single-locus trees was very similar and the ILD test confirmed the congruence between them (p = 0.001). The combined dataset consisted of an equal number of nrSSU and nrLSU sequences relative to 39 taxa (including MUT 4937 and MUT 5443) that represented 23 genera and 33 species (Table
The two isolates MUT 4937 and MUT 5443 clustered within the family Juncigenaceae together with Marinokulati chaetosa, Khaleijomyces marinus, Juncigena adarca, J. fruticosae, Fulvocentrum aegyptiacum, and F. clavatisporum (Fig.
Elbamycella rosea sp. nov.
In reference to the geographic isolation site, Elba Island, Tuscany (Italy)
Juncigenaceae, Sordariomycetes, Ascomycota. The genus Elbamycella gen. nov. clusters together with genera Marinokulati, Khaleijomyces, Juncigena, and Fulvocentrum (Fig.
Ascomata superficial, erumpent or immersed, perithecial, scattered or gregarious, olivaceous-brown to black at maturity, globose, subglobose, ovoid or pyriform, glabrous; ostiolar neck long, pale-coloured; peridium of textura prismatica in the outer layers and textura globulosa in the inner layers. Asci evanescent, hyaline, cylindrical to clavate.
Ascopores cylindrical rounded at both ends, thin-walled, hyaline, straight or slightly curved, 3-septate, bearing subpolar, appendages.
Asexual morph unknown.
Italy, Tuscany, Mediterranean Sea, Elba Island (LI), Ghiaie ISL, 14–15m depth, 42°49’04”N, 10°19’20”E, on the brown alga Padina pavonica, 20 March 2010, R. Mussat-Sartor and N. Nurra, MUT 5443 holotype, living culture permanently preserved in metabolically inactively state by deep-freezing at Mycotheca Universitatis Taurinensis. A dried specimen of this culture grown on CMASS and CMASW has been deposited in the herbarium of the Department of Life Sciences and Systems Biology (TO Cryptogamia 3446).
Italy, Tuscany, Mediterranean Sea, Elba island (LI), Ghiaie ISL, 14–15m depth, 42°49’04”N, 10°19’20”E, on the seagrass Posidonia oceanica, 20 March 2010, R. Mussat-Sartor and N. Nurra, MUT 4937 = CBS 130520.
In reference to the colour of the colony on the culture media.
Ascomata were produced on both CMASS and CMASW at 21 °C only, after 28 days of incubation. Mycelium hyaline to pale brown consisting of smooth-walled hyphae 2.5–4 µm wide (Fig.
Ascomata perithecial, scattered or gregarious (from 2 to 6-8), superficial, erumpent or immersed, olivaceous-brown to black at maturity, globose, subglobose, ovoid or pyriform, glabrous, up to 100–140 µm diameter; ostiolar neck, pale-coloured, single (sometimes 2, rarely 3), 55–70 µm long and 20–50 µm wide at the base; peridium 5–10 µm thick of textura prismatica in the outer layers and textura globulosa in the inner layers with cells with olivaceous-brown walls, in the neck consisting of hyaline, more elongated cells, from which numerous hyaline blunt hyphal projections 5–15 × 3–5 µm arise. Asci evanescent, hyaline, cylindrical to clavate 22–26 × 12–16 µm containing 8 spores; sterile elements not observed (Fig.
Ascopores cylindrical 23–28 × 4–5 µm, rounded at both ends, thin-walled, hyaline, straight or slightly curved, 3-septate, with a large basal cell 10–15 µm long and 3 shorter, upper cells, slightly constricted around the septa, the apical cell somewhat attenuated just below the blunt tip, bearing 3(4) subpolar, straight or slightly bent, acuminate, hyaline, smooth-walled cellular appendages 10–20 µm long (about 0.5–1 µm wide). In some spores the apical cell is divided by an additional septum; each cell of the spore contains a few oil-droplets 1.5–3.0 µm diameter (Fig.
Asexual morph not observed.
Colonies reaching 21–23 mm diameter on CMASW and 19–29 mm diameter on CMASS in 28 days at 21 °C, plane, thin, mycelium mainly submerged. Colonies pale pink in the centre becoming brown with age, colourless at the margins. Black spots due to ascomata groups in fruiting colonies. Reverse of the same colour of the surface (Fig.
Colonies on PDASW and PDASS reaching 10–14 mm diameter in 28 days at 21 °C, convolute, developing in height with irregular margins, salmon. Reverse of the same colour of the surface (Fig.
At 10 °C colony growth on all media very poor, attaining 5–8 mm diameter in 28 days. Colonies plane to slightly convolute with regular margins, pale pink to cyclamen. Reverse of the same colour of the surface (Fig.
Comparison of the main sexual morpholgical features of genera belonging to Juncigenaceae.
Fungus | Ascomata | Periphyses/ Paraphyses | Asci | Ascospores | Reference |
Marinokulati chaetosa | Immersed to superficial, dark brown, ostiolate, papillate; neck 20 × 70 µm | Both present, septate, wide | 102−135 × 12−18 µm; cylindrical to clavate, attenuate at the base, thick-walled at the apex, containing 8 spores | 25.5−36.5 × 7.5−11.5 µm; 3-septate, hyaline, fusiform to ellipsoidal with polar and equatorial appendages |
|
Khaleijomyces marinus | Superficial to immersed, hyaline to yellow-orange to reddish brown, ostiolate; 110−175 × 100−115 µm; neck 120-175 × 40-50 µm | Periphyses present in the neck | 60−98 × 12−16 µm; cymbiform to fusiform, thin-walled, with no apical apparatus, containing 8 spores | 12−26 × 6-8 µm; 1-4-septate; ellipsoidal to fusiform; hyaline, smooth-walled |
|
Juncigena adarca | Immersed, ostiolate, papillate, 225−400 × 135-200 µm; neck 85−170 × 50−85 µm | Both present; Paraphyses thin, branched, septate | 115−140 × 10−13 µm; fusiform to cylindrical, short pedunculate, apical apparatus with a ring, containing 8 spores | 26.5−34.5 × 6−7 µm; 3-septate, hyaline, fusiform to ellipsoidal, no appendages, smooth wall, constricted |
|
Fulvocentrum aegyptiacum | Immersed, dark brown, ostiolate; 240−280 × 170−190 µm; neck 70−80 µm diameter | Both present; Paraphyses numerous, in a gel, unbranched | 145−155 × 9−10 µm; Short pedicellate, apically thickened, containing 8 spores | 15−20 × 6−8 µm; 3-septate, ellipsoidal, hyaline |
|
Fulvocentrum clavatisporum | Immersed, dark brown, ostiolate; 160−170 × 160−190 µm; neck 50 µm long | Both present; Paraphyses numerous, in a gel, unbranched | 80−96 × 10−13µm; Pedicellate, apically thickened, containing 8 spores | 25−28 × 5−6 µm; 3-septate, clavate, hyaline |
|
Fulvocentrum rubrum | Erumpent to superficial, olive-brown to dark brown, ostiolate; 145−270 µm; neck 310−390 × 50−55 µm | Both present | Fusiform or obclavate, 95−130 × 13−19 µm; persistent, thin-walled, containing 8 spores | Ellipsoidal to clavate, no appendages, 25−33 × 6−9 µm; hyaline to faint apricot, smooth walled, 3−5-septate |
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Elbamycella rosea sp. nov. | Superficial, erumpent or immersed; 100–140 µm diam; olivaceous-brown to black; ostiolar neck 55−70 × 20–50 µm | Cylindrical to clavate 22−26 × 12−16 µm containing 8 spores | Cylindrical 23−28 × 4−5 µm; hyaline, generally 3-septate, bearing 3(4) subpolar appendages 10–20 × 0.5–1 µm | This study |
The novel genus Elbamycella is introduced in this study and has been compared to the closest genera. Herein, the two strains MUT 4937 and MUT 5443 represented a new species that formed a well-supported cluster phylogenetically distant from the related genera of Juncigenaceae.
From a morphological point of view, the relatedness with the other species belonging to Juncigenaceae is confirmed by i) 3-septate spores (1–4 only in K. marinus), ii) 8-spored asci, and iii) ascomata with an elongated neck (
As no sexual form is known for J. fruticosae, the comparison with E. rosea sp. nov. is not possible. However, the similarity or identity to this species is excluded by the phylogenetical distance.
Ecologically, the described Juncigenaceae are species having a marine origin. So far, they have all been retrieved from driftwood in the intertidal of salt marshes (
This work was funded by Fondazione CRT, Turin, Italy. The authors are grateful to Pelagosphera s.c.r.l. for harvesting algal and seagrasses samples.