Cyttaria Berk., Trans. Linn. Soc. London 19:40 (1842)

This genus is geographically restricted to South America (Argentina and Chile) and Southeastern Australasia (including Tasmania, and New Zealand) (Peterson and Pfister 2010). Cyttaria species are found in the secondary phloem and xylem, cambium and cortex of the hosts. They produce trunk and branch cankers that arise due to localized, stimulated cambial activity attributed to the presence of hyphae of Cyttaria (Wilson 1937; Gutierrez de Sanguinetti 1988). Cyttaria species are considered as weak parasites (Gamundı´ and Lederkremer 1989). 

Classification Leotiomycetes, Leotiomycetidae, Cyttariales, Cyttariaceae

Type speciesCyttaria darwinii Berk., Trans. Linn. Soc. London 19:40 (1842)

Distribution – Argentina, Australia, Chile, New Zealand, Tasmania.

Disease symptoms – Canker, galls

        These species are known to cause two types of cankers: globose and longitudinal. Globose cankers arise from growth mainly in the transverse axis of the branch while longitudinal cankers arise from growth mainly along the long axis (Rawlings 1956; Gamundi 1971). The development of perennial galls on branches and stems may lead to malformation and occasional death of branches (Gadgil 1985).

HostsNothofagus spp.


Morphological based identification and diversity

Ascomata of Cyttaria species are orange, pitted apothecia similar to deeply dimpled golf balls. Each fruiting body is composed of 1–200 apothecia immersed in a sterile fleshy-gelatinous stroma. Asci are 8-spored, inoperculate and amyloid. Ascospores are uninucleate, subglobose to ovoid, smooth to rugulose, at first hyaline to yellowish but later becoming pigmented (Mengoni 1986; Peterson et al 2010). There are 21 epithets listed in Index Fungorum (2019).


Molecular based identification and diversity

The first phylogenetic analysis which included Cyttaria was done by Gargas and Taylor (1995) showing its relationship with other discomycetes. Ekanayaka et al. (2017) Wang et al. (2006) showed its placement within Leotiomycetes using combined analysis of SSU, LSU, and 5.8S rDNA gene sequence data and then confirmed by Ekanayaka et al. (2017). Peterson and Pfister (2010) did large scale phylogeny for Cyttaria including all accepted 12 species in the genus using sequence data of partial nucSSU, nucLSU, and mitSSU rRNA, as well as TEF1. They found Cyttaria to be a strongly supported clade and suggested a close relationship between Cyttaria and some members of the Helotiales (Cordierites, Encoelia, Ionomidotis, and Chlorociboria) (Peterson and Pfister 2010). The present study reconstructs the phylogeny of Cyttaria based on analyses of a combined LSU, SSU and mtSSU sequence data (Table 5, Fig. 10). The phylogenetic tree is updated with recently introduced Cyttaria species and corresponds to previous studies (Feng et al. 2014; Gao et al. 2015).


Recommended genetic markers (genus level) – ITS, LSU

Recommended genetic markers (species level) – nucSSU, nucLSU, mitSSU rRNA, and tef1

Combined nucSSU, nucLSU, mitSSU rRNA, and tef1 can resolve almost all species of Cyttaria currently known from sequence data (Peterson et al 2010).


The accepted number of species: There are 21 epithets in Index Fungorum (2019). However, 12 species have molecular data and are treated as accepted.

References: Mengoni 1986, Peterson et al 2010 (morphology); Peterson and Pfister (2010), Ekanayaka et al. 2017 (morphology, phylogeny).


Table Details of Cyttaria isolates used in the phylogenetic analyses. Ex-type (or ex-epitype) strains are in bold and marked with an asterisk* and voucher strains are in bold.

 Species Isolate/Voucher no LSU SSU mtSSU
C. berteroi isolate 16 EU107205 EU107178 EU10723
C. darwinii isolate 40 EU107207 EU107180 EU107236
C. darwinii isolate 14 EU107208 EU107181  —
C. darwinii isolate 57 EU107206 EU107179 EU107235
C. darwinii isolate 45 EU107209  —  —
C. darwinii isolate 50 EU107211  —  —
C. darwinii isolate 49 EU107210  —  —
C. espinosae isolate 187  — EU107183 EU107238
C. espinosae isolate 92 EU107212 EU107182 EU107237
C. exigua isolate 77 EU107214 EU107185 EU107240
C. exigua isolate 76 EU107213 EU107184 EU107239
C. gunnii isolate 138  — EU107189 EU107242
C. gunnii isolate 127 EU107215 EU107186 EU107241
C. gunnii isolate 136  — EU107188  —
C. gunnii isolate 132  — EU107187  —
C. hariotii isolate 44 EU107217 EU107194 EU107245
C. hariotii isolate 55 EU107218 EU107195 EU107246
C. hariotii isolate 65 EU107223  —  —
C. hariotii isolate 64 EU107222  —  —
C. hariotii isolate 63 EU107221  —  —
C. hariotii isolate 62 EU107220  —  —
C. hariotii isolate 51 EU107219  —  —
C. hookeri isolate 60 EU107227  —  —
C. hookeri isolate 59 EU107226  —  —
C. hookeri isolate 80 EU107228  —  —
C. hookeri isolate 61 EU107225 EU107197  —
C. hookeri isolate 58 EU107224 EU107196  —
C. johowii isolate 73 EU107229 EU107198  —
C. johowii isolate 74 EU107230 EU107199  —
C. nigra isolate 100 EU107232 EU107201 EU107248
C. nigra isolate 97 EU107231 EU107200 EU107247
C. septentrionalis isolate 199  — EU107203 EU107249
C. septentrionalis isolate 85  — EU107202  —

Fig. Phylogram generated from RAxML analysis based on combined sequences of LSU, SSU and mtSSU sequences of all the accepted species of Cyttaria. Related sequences were obtained from GenBank. Thirty-four strains are included in the analyses, which comprise 3480 characters including gaps. Single gene analyses were carried out and compared with each species, to compare the topology of the tree and clade stability. The tree was rooted with Chlorociboria cf. aeruginosa (OSC 100056). The best scoring RAxML tree with a final likelihood value of -7505.900855 is presented. The matrix had 360 distinct alignment patterns, with 39.17% of undetermined characters or gaps. Estimated base frequencies were as follows; A = 0.256, C = 0.214, G = 0.280, T = 0.250; substitution rates AC = 1.190197, AG = 1.207782, AT = 0.373130, CG = 0.681125, CT = 3.724394, GT = 1.000000; gamma distribution shape parameter α = 0.020000. RAxML and maximum parsimony bootstrap support value ≥50% (BT) are shown respectively near the nodes.

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