Abstract

INTRODUCTION

Fungi classified in the genus Septoria Sacc. are asexual morphs of Ascomycota causing leaf spot diseases on many cultivated and wild plants. Some 3000 Septoria names have been described in literature (Verkley et al. 2004a, b). Sexual morphs are unknown for most taxa, but those reported were mostly classified in Mycosphaerella and Sphaerulina (Von Arx 1983, Sutton & Hennebert 1994, Crous et al. 2000, Verkley & Priest 2000, Crous et al. 2001, Aptroot 2006). Several overviews of the taxonomic work done on these fungi have been provided in the literature (Shin & Sameva 2004, Priest 2006, Quaedvlieg et al. 2013). Priest (2006) discussed the complex nomenclatural history of Septoria. The type species of Septoria, S. cytisi, is a fungus occurring on the woody legume Cytisus laburnum (= Laburnum anagyroides) and several other, mostly herbaceous Fabaceae (Farr 1992, Muthumary 1999). The phylogenetic position of this species for which no cultures are available has for long been uncertain. However, using well-identified herbarium material, Quaedvlieg et al. (2011) were able to extract DNA and successfully amplify and sequence nuclear ribosomal RNA genes to determine its position in a comprehensive phylogeny inferred for Mycosphaerellaceae.

Most taxonomists adopted a generic concept of Septoria that included fungi forming pycnidial conidiomata with holoblastic, hyaline, smooth-walled conidiogenous cells with sympodial and/or percurrent proliferation and hyaline, smooth, filiform to cylindrical multi-septate conidia (Sutton 1980, Constantinescu 1984, Sutton & Pascoe 1987, 1989, Farr 1991, 1992). Similar fungi forming acervular conidiomata were classified in Phloeospora, with Phloeospora ulmi as the type species, yet some researchers adopted a broader concept to include Phloeospora in Septoria (Jørstad 1965, Von Arx 1983, Andrianova 1987, Braun 1995). Recent DNA-sequencing studies have shown that the morphological characters that were used to delimit coelomycete genera in the past, in particular those pertaining to conidiomatal structure and conidiogenesis, did not correlate well with the sequence-inferred phylogenies (Crous et al. 2001, Verkley et al. 2004a, b). Quaedvlieg et al. (2013) present in their broad-scope study the results of an in-depth morphological and multi-gene sequence analyses of the septoria-like genera based on numerous isolates (including S. cytisi). In their study, they resolve the affinities and settle the nomenclature of all important septoria-like genera in the Dothideales and Pleosporales.

Host specificity has long been a decisive criterium in species delimitation in Septoria, mainly because of the paucity of useful morphological characters and the high level of variation therein. Traditionally, species of Septoria that were morphologically very similar but found on plants of different host families, were regarded as distinct taxa. Material from the same genus or from closely related host genera from the same plant family that could be distinguished by features such as conidial length and/or width and septation were usually also considered to belong to separate species. Most taxonomists revising Septoria lacked facilities to thoroughly investigate host ranges. A number of economically important Septoria species and species complexes have been subjected to infection experiments on various hosts, viz. the pathogens of Apium (Cochran 1932, Sheridan 1968) and cultivated Chrysanthemum (Waddell & Weber 1963, Punithalingam & Wheeler 1965). The results of these studies largely seemed to confirm the general belief that Septoria species have host ranges that are limited to a single genus of plants and in relatively few cases, also include a few closely related genera from the same plant family (Priest 2006). Molecular phylogenetic studies on Septoria species infecting Asteraceae (Verkley & Starink-Willemse 2004) and woody perennials (Feau et al. 2006) showed that species that are capable of infecting hosts of the same plant family do not (always) cluster in monophyletic groups, which is indicative of disjunct evolutionary patterns of these pathogens and their hosts. To explain these patterns, it has been postulated that “host jumping” occurs from typical (susceptible) hosts to “non-host” plants through asymptomatic tissue infection and subsequent exploration of new susceptible hosts. Examples of this were found in certain Mycosphaerella species and their Acacia hosts (Crous et al. 2004b, Crous & Groenewald 2005), but the mechanisms driving host jumping are not yet understood. With our study in which we investigate the phylogenetic relationships of species from a wider spectrum of host families we hope to provide more insight into the evolution of these fungal pathogens and their host plants and to contribute to understanding such mechanisms.

Early molecular phylogenetic studies have confirmed the relationships of septoria-like fungi with sexual morphs within Mycosphaerellaceae, and that the septoria-like fungi are of poly- and paraphyletic origins (Stewart et al. 1999, Crous et al. 2001, Goodwin et al. 2001, Verkley et al. 2004a, b, Verkley & Starink-Willemse, 2004). The ITS and/or LSU nrDNA sequence data used in those studies did not provide sufficient phylogenetic information to discriminate closely related species nor resolve most of the internal nodes in the trees. Verkley et al. (2004a, b) already concluded that groups within the then known “Mycosphaerella clade” showed no correlation to conidiomatal structure or conidiogenesis, confirming the conclusions drawn by Crous et al. (2001). Feau et al. (2006) sequenced the ITS, partial β-tubulin gene, and a proportion of the mitochondrial small subunit ribosomal gene (mtSSU) to infer a phylogeny for Septoria associated with diseases of woody perennials (many of which are here transferred to Sphaerulina). Although their inferred trees provided improved resolution, it was clear that even more DNA loci would be needed to fully resolve closely related species and species complexes within Septoria s. str.

The primary goal of our work was to improve the taxonomy of Septoria by adopting a polyphasic approach to taxon delimitation. To this end we studied cultures preserved in CBS, Utrecht, the Netherlands and material freshly collected in the field, did a full characterisation of the morphology in planta and in vitro, and sequenced seven DNA loci, viz. nuclear ITS and (partial) LSU ribosomal RNA genes, and RPB2, actin (Act), calmodulin (Cal), β-tubulin (Btub), and translation elongation factor 1-alpha (EF) genes. The obtained datasets of the seven loci were also evaluated for PCR amplification success rates and barcode gaps in order to determine which individual, or combination of loci, would be best suited for fast and reliable species resolution and identification.

Most students of Septoria have focused on material on the natural substrate and did not isolate and deposit cultures in public culture collections. Of all material we were able to successfully isolate, cultures were deposited in CBS-KNAW Fungal Biodiversity Centre (CBS) in Utrecht, The Netherlands. To assess the nomenclature this material was compared to type material as far as it could be obtained for study. Where useful new material and associated pure cultures were designated as epitypes, to facilitate future work. This study supplements the work of Quaedvlieg et al. (2013), who attain a broader perspective and address the complicated taxonomy and polyphyly of septoria-like fungi, proposing several new genera for taxa that are distantly related to Septoria cytisi and allied species.

MATERIAL AND METHODS

RESULTS

Identification of the best DNA barcode loci for Septoria species

Amplification success

The PCR amplification success rates were very high for all seven loci, varying from 97 % for RPB2 to 100 % for ITS and LSU (Table 3). Good amplification reactions of RPB2 required a 2-3 times higher DNA input then the other loci and this locus is therefore less favorable for easy identification. The other six loci amplified without problems.

Kimura-2-parameter values

The Kimura-2-parameter (K2P) distribution graphs are depicted in Fig. 1. They visualise the inter- and intraspecific distances per locus (barcoding gap). A good barcoding locus should have no overlap between the inter- and intraspecific K2P distances and should have an average interspecific distance that is at least 10 times as high as the average intraspecific distance of that locus (Hebert et al. 2003). The seven loci show a rather constant degree of intraspecific variation of 0.01 in their K2P distribution graphs, however their interspecific variations shows considerable differences. The average interspecific variation in both ITS and LSU datasets is very low (0.015) compared to their intraspecific variation (0.01), leading to a very low inter- to intraspecific variation ratios of 1.5: 1 for these two loci (Fig. 1). These low ratios are far below the required 10: 1 ratio, indicating a general lack of natural variation within these two loci, making them ill-suited for effective identification of the individual species used in this dataset. These low K2P results for ITS and LSU are consistent with previous results by Verkley et al. (2004a, b) which showed that both loci could not resolve the lower phylogenetic relationships between closely related Septoria species. Due to the presence of intron regions in the five remaining protein coding loci, these genes provide much higher interspecific variation than the more conserved ITS and LSU loci. These protein coding genes thus have (much) higher K2P inter- to intraspecific variation ratios: for Cal 14: 1, RPB2 17: 1, Act 23: 1, EF 26: 1 and for Btub 29: 1 (Fig. 1), making them all suitable for reliable species resolution throughout the range of septoria-like fungi. As the EF and Btub have the largest barcoding gap, these loci should give the highest species resolution and preferably be used for identifying species.

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Fig. 1.

Frequency distributions of the Kimura-2-parameter distances (barcoding gaps) for the seven PCR loci.

Phylogeny

Basal to the seven-locus tree are the outgroup taxon Readeriella mirabilis (CBS 125000), and a monophyletic group comprising 11 strains, viz. Dothistroma pini (CBS 121011), D. septospora, (CBS 383.74), Passalora dissiliens (CBS 219.77), three Ramularia species (Mycosphaerella s. str., see Quaedvlieg et al. 2013) and three Zymoseptoria species, including its type species Z. tritici (syn. Mycosphaerella graminicola, Septoria tritici). The basal ingroup taxa include CBS 619.72 identified as Septoria oudemansii, a Pseudocercospora clade with six strains, and Cercosporella virgaureae (CBS 113304). A well-supported cluster of two basal lineages (bootstrap support 100 %) comprises a cluster (100 %) of two isolates identified as S. gladioli, and a second cluster (100 %) containing 10 strains representing four septoria-like species that are all associated with leaf spots on plants of the family Caryophyllaceae, and for which the new generic name Caryophylloseptoria is proposed below. These include C. silenes (CBS 109100, 109103), C. lychnidis (CBS 109098-109102), two isolates originating from Lychnis cognata in Korea for which the new species C. pseudolychnidis is proposed by Quaedvlieg et al. (2013) (CBS 128614, 128630), and two isolates of C. spergulae (CBS 397.52, 109010).

The remaining ingroup can be devided into a Sphaerulina clade (100 %, 51 strains including the basal strain of Sph. abeliceae, CBS 128591) and main Septoria clade (80 %, 259 strains) with, positioned in between smaller groups comprised of “Septoria” cruciatae (CBS 123747, 123748), a small pseudocercosporella-like clade comprising Passalora fusimaculans (CPC 17277), a clade with Passalora depressa (CPC 14915), “Mycosphaerella” brassicicola and affiliated taxa with Pseudocercosporella asexual morphs (100 %, 9 strains), and a miscellaneous clade containing “Passalora” sp. (100 %, CBS 113989, 113999, 114275), Passalora dioscoreae (CPC 10855, 11513), Pseudocercosporella magnusiana (CBS 114735), Passalora janseana (CBS 145.37), “Septoria erigerontis” (CPC 19485), and a Cercospora clade (100 %, 4 strains).

The Sphaerulina clade comprises the aforementioned CBS 128591 identified as S. abelicaea (from Zelkova serrata) and clades 1 and 2. Clade 1 (100 %, 37 strains) includes at its base three strains of Sph. cornicola, the sister taxa Sph. betulae and S. westendorpii (syn. S. rubi) on Rubus fruticosus (CBS 102327, 109002, 117478), and Sph. socia (CBS 355.58, CBS 357.58). The remainder of clade 1 contains a well-supported cluster of 25 strains with various species infecting herbaceous and woody hosts. CBS 109017 and 19018, originating from Rubus idaeus in Austria, represent a species for which Sphaerulina tirolensis sp. nov. is introduced below. Furthermore this cluster contains Sphaerulina berberidis (syn. Mycosphaerella berberidis, S. berberidis Niessl), Sph. azaleae, Sph. hyperici, Sph. menispermi, Sph. patriniae, Sph. cercidis, and Sph. gei. Clade 2 (74 %, 13 strains) of the Sphaerulina clade includes only species infecting tree, the poplar pathogens Sph. populicola (syn. Mycosphaerella populicola, CBS 100042), Sph. musiva (syn. Septoria musiva, four strains), and Sph. frondicola (syn. Mycosphaerella populi, S. populi, CBS 391.59), and furthermore Sphaerulina aceris (syn. Mycosphaerella latebrosa, Phloeospora aceris, asexual morph S. aceris, three strains), which causes leaf spot on Acer spp., and Sph. quercicola (syn. S. querciola).

At the base of the main Septoria clade, a well-supported clade 3 (88 %, 16 strains) includes several species associated with hosts in the Apiaceae, viz., S. oenanthis (CBS 128667) and S. oenanthicola (CBS 128649; a new species proposed by Quaedvlieg et al. (2013), S. sii (CBS 118.96, 102369, 102370), and S. aegopodii (CBS 123740, 123741), and associated with other plant families, S. dearnessii (CBS 128624), a cluster of two strains of S. lactucae (CBS 352.58, 108943) and S. sonchi (CBS 128757), S. campanulae (CBS 128589, 128604), S. mazi (CBS 128656, 128755), and S. gentianae (CBS 128633). In clade 4 (100 %, 183 strains) S. bupleuricola (CBS 128601, 128603) and S. scabiosicola (100 %, 12 strains) occupy a basal position and subclades 4a-d can be distinguished. Subclade 4a (100 %, 46 strains) comprises of a group of 13 strains of miscellaneous host plants, mostly with smaller conidia, viz., two Solanum pathogens S. lycopersici (CBS 354.49, 128654) and S. malagutii (CBS 106.80), S. apiicola (4 strains), S. cucurbitacearum (CBS 178.77), and S. aridis (4 strains), and a second strain identified as S.posonniensis (CBS 128658). Subclade 4b (100 %, 33 strains) harbours several taxa infecting Asteraceae, among others S. obesa (four strains), S. senecionis (three strains), S. putrida (CBS 109087, 109088), S. leucanthemi (6 strains), S.cirsii (CBS 128621), six strains of the S. chrysanthemella complex, S. exotica (CBS 163.78), and S. posoniensis (CBS 128645). Furthermore this group of 33 comprises taxa with relatively large conidia capable of infecting Ranunculaceae, viz. S.lycoctoni, S. napelli (CBS 109104-109106) from Austria and S. pseudonapelli (CBS 128664; a new species proposed by Quaedvlieg et al. 2013) from Korea. It also includes S. lycopicola (128651), CBS 128662 identified as S. stachydicola (probably misidentified), and two strains of S. astericola (CBS 128587, 128593). Subclade 4c (99 %, 15 strains) contains S. matricariae (CBS 109000, 109001), S. lamiicola (8 strains), S. anthrisci (CBS 109019, 109020), and S. petroselini (CBS 182.44, 109521), and subclade 4d (100 %, 103 strains) shows four subgroups, 4d-1-4. Basic to these are found S. dolichospora (CBS 129152) and S. helianthi (CBS 123.81). Subclade 4d-1 (100 %, 45 strains) contains S. cf. stachydicola (CBS 128668; see Quaedvlieg et al. 2013), and many other species infecting herbaceous plants, among others S. stachydis (nine strains), S. phlogis (three strains), S. epambrosiae (CBS 128629, 128636), S. cerastii (five strains), S. galeopsidis (seven strains), S. stachydis (9 strains), S. epilobii (CBS 109084, 109085) and S. digitalis (CBS 391.63, 328.67). Subclade 4d-2 (100 %, 35 strains) comprises among others S. polygonorum (six strains), S. urticae and S convolvuli (three strains each), S.villarsiae, S. crepidis, and S. codonopsidis. Subclade 4d-3 (99 %, 11 strains) containing S. erigerontis (five strains), S. lysimachii (five strains), and S. saccardoi (CBS 128756). Subclade 4d-4 (100 %, 9 strains) contains S. bothriospermi (CBS 128592, 128599), S. tinctoriae (CBS 129154), four strains identified as S. rubi that need to be re-named, and S.agrimoniicola (CBS 128585, 128602).

In clade 5 (92 %, 63 strains) of the main Septoria clade two main clusters are found. At the base of the subclade 5a (77 %, 52 strains), two strains of S. clematidis (CBS 108983-4) and Septoria sp. (CPC 19716) originating from Searsia laevigatum in South Africa. This cluster furthermore comprises three strains isolated from Hibiscus spp., viz., S. hibiscicola (CBS 128611, 128615) and S. abei (CBS 128598), and two main groups, one with S. anthurii (CBS 148.41, 346.58), S. sisyrinchii (CBS 112096), the Chromolaena fungi S. chromolaenae (CBS 113373) and S. ekmanniana (CBS 113385, 113612), and S. passiflorae (CBS 102701) and S. passifloricola (CBS 129431), and a second group comprising at the base S. eucalyptorum (CBS 118505; Crous et al. 2006b), and furthermore S. justiciae (CBS 128610, 128625, and CPC 12509), S. linicola (CBS 316.37), S. cucubali (3 strains, including CBS 124874, an endophytic isolate from Fagus leaf litter), S. lepidiicola (CBS 128635) and and a partially unresolved cluster of 23 strains comprising the plurivorous S. protearum and S. citri complex. A small well-supported cluster (100 %) contains S. verbenae (CBS 113438, 113481), two unidentified species of Septoria (CPC 19304, from Vigna unguiculata subsp. sesquipedalis and CPC 19793, from Syzygium cordatum), and M. coacervata (CBS 113391). Subclade 5b (100 %, 11 strains) comprises S. helianthicola (CBS 122.81), three strains of S. stellariae, CBS 503.76 identified as S. acetosae, three strains of S. astragali, “Cercospora sp.” (CBS 112737), and furthermore S. hippocastani (CBS 411.61 and MP11).

Examining the distribution of host families throughout the tree, an interesting disjunct pattern is found for the families that are represented by more than a few specimens (see legend in Fig. 2). For example, the 28 species infecting Asteraceae are found in all clades and most subclades of the tree, including Sphaerulina; nine species infecting Apiaceae are found in clade 3 and subclades 4a-d of Septoria; 10 species of Rosaceae in Septoria clades 4, 5 and Sphaerulina (clades 1 and 2); six species infecting Lamiaceae are dispersed in subclades 4b, c, and d-1.

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Fig. 2.

Consensus phylogram (50 % majority rule) of 17 222 trees resulting from a Bayesian analysis of the combined seven loci sequence alignment using MrBayes v. 3.2.1. Bayesian posterior probabilities values are indicated on their respective branches and the scale bar indicates 0.2 expected changes per site. The tree was rooted to Readeriella mirabilis (Teratosphaeriaceae) (CBS 125000). The family of the host plant from which the strain was isolated is indicated for 12 most prevalently occurring host families in our dataset (colour bar according to the legend).

TAXONOMY

Caryophylloseptoria Verkley, Quaedvlieg & Crous, gen. nov. MycoBank MB804469.

Etymology: Named after the plant family on which these taxa occur, Caryophyllaceae.

Conidiomata pycnidial, epiphyllous or predominantly epiphyllous, globose to subglobose, or slightly depressed, with a central ostiolum. Conidiomatal wall composed of textura angularis or globulosa-angularis. Conidiogenous cells hyaline, holoblastic, proliferating percurrently 1-many times with indistinct annellations, or (in addition) proliferating sympodially. Conidia cylindrical, straight, curved or flexuous, multiseptate, not or somewhat constricted around the septa, hyaline, contents with several oil-droplets and granular material in each cell.

Type species: Caryophylloseptoria lychnidis (Desm.) Verkley, Quaedvlieg & Crous.

Caryophylloseptoria lychnidis (Desm.) Verkley, Quaedvlieg & Crous, comb. nov. MycoBank MB804470. Fig. 3.

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Fig. 3.

Caryophylloseptoria lychnidis. A. CBS 109098, colony on OA. B. Ibid., on CMA. C. Conidia and conidiogenous cells in planta (CBS 109098). D. Conidia on OA (CBS 109098). Scale bars = 10 μm.

Basionym: Septoria lychnidis Desm., Annls Sci. Nat., sér. 3, Bot. 11: 347. 1849.

For extended synonymy see Shin & Sameva (2004).

Description in planta: Symptoms leaf spots circular, whitish to pale yellow, surrounded by a brown border; Conidiomata pycnidial, epiphyllous, several in each leaf spot, globose to subglobose, dark brown, semi-immersed, 50-100(-120) μm diam; ostiolum central, initially circular, 25-45 μm wide, later more irregular and up to 100 μm wide, surrounding cells concolorous or somewhat darker; conidiomatal wall 10-20μm thick, composed of textura angularis without distinctly differentiated layers, the cells 3-5 μm diam, the outer cells with brown, somewhat thickened walls, the inner cells with hyaline and thinner walls; Conidiogenous cells hyaline, cylindrical and tapering gradually towards the apex, or narrowly ampulliform with a relatively wide and long neck, holoblastic, proliferating percurrently 1-many times with indistinct annellations, rarely also proliferating sympodially, 6-17.5(-22) × 3-4(-5) μm. Conidia cylindrical, straight, more often slightly curved or flexuous, with a narrowly to broadly rounded, sometimes more distinctly pointed apex, towards the broadly truncate base barely attenuated, (0-)3-5(-7)-septate, not constricted around the septa, hyaline, contents with several oil-droplets and minute granular material in each cell in the living state, with inconspicuous oil-droplets and granular contents in the rehydrated state, (22-)39-75(-85) × 2-3 μm (rehydrated). Sexual morph unknown.

Description in vitro: Colonies on OA (3-)4-6 mm diam in 12 d (7-11 mm in 3 wk), with an even, pure yellow to straw, glabrous margin, the pigment diffusing into the surrounding medium; colonies spreading, but in the centre quite distinctly elevated, immersed mycelium pure yellow to straw, later locally citrine-green or citrine; after 10-15 d darkened by numerous immersed or superficial pycnidia arranged in random patterns, the outer wall of the superficial pycinidia entirely covered by white to glaucous hyphae, tardily releasing initially buff to straw, later salmon conidial slime; reverse pure yellow, but centre olivaceous and citrine to greenish olivaceous after 3 wk. After incubation over about 7 wk olivaceous-black sectors become visible in the colony consisting mostly of immersed strands of dark-walled hyphae, alternating with yellow sectors; some colonies develop wider sectors that remain yellow above, but more ochreous on reverse. Colonies on CMA 4-6 mm diam in 12 d (9-12 mm in 3 wk), as on OA, but sporulating earlier. Colonies on MEA 2-4 mm diam in 12 d (5-7(-9) mm in 3 wk; 17-24 mm in 7 wk), with an even to ruffled, colourless to buff, glabrous margin; no diffusing pigment seen; colonies restricted, irregularly pustulate up to 3 mm high, the surface dark, blackish or chestnut, covered by a short, dense mat of white to glaucous-grey, after 7 wk straw to pale yellow, aerial mycelium; conidiomata releasing droplets, later larger masses of first whitish, then salmon conidial slime; reverse brown-vinaceous in the centre, surrounded by hazel or cinnamon areas. Colonies on CHA 4.5 mm diam in 3 wk (24 mm in 7 wk); colony as on MEA, but the surface almost entirely hidden under a dense mat of woolly, white aerial mycelium, locally with a pure yellow to straw haze which later becomes more intense, and a yellowish pigment diffusing into the surrounding medium; reverse umber to sienna; densely aggregated superficial conidiomata in the centre releasing masses of amber to pale salmon conidial slime. Conidiomata pycnidial, as in planta, but somewhat larger, 70-145 μm diam, mostly single, sometimes merged into complexes, without differentiated ostiolum; conidiogenous cells as in planta, proliferating percurrently with distinct annellations or sympodially, 8.5-25 × 3.5-6 μm; conidia cylindrical, straight, slightly curved or flexuous, with a rounded apex, lower part barely attenuated into a broad truncate base, (0-)1-5-septate, not constricted around the septa, hyaline, with several oil-droplets and minute granular material in each cell, (44-)77-94.5 × (2-)2.5-3 μm.

Hosts: Lychnis spp. and Silene spp. (incl. Melandrium).

Material examined: Austria, Tirol, Inntal, near Telfs, on living leaves of Silene pratensis (syn. M. album), 4 Aug. 2000, G. Verkley 1047, CBS H-21161, living culture CBS 109098, 109102; same loc., host, date, G. Verkley 1048, CBS H-21162, living culture CBS 109099, 109101; Netherlands, Hilversum, on living leaves of Silene dioica (syn. Melandrium rubrum), 22 June 1985, H.A. van der Aa 9524, CBS H-18112.

Notes: This fungus has been reported from several species of Lychnis and Silene (including Melandrium), and the size ranges of conidia given by various authors differ considerably. In the original description by Desmazières, the fungus was characterised as having 5-7-septate conidia, measuring 50-70 ×2.5-3 μm, in widely opening pycnidia. Diedicke (1915) gave the same spore measurements, but Grove (1935) reported 30-50 × 2-3 μm, while Jørstad (1965) gave different ranges on different hosts (overall extremes 27-72 × 2-3 μm). Radulescu et al. (1973) reported 30-76 × 2.2-3.3 μm, and Vanev et al. (1997) 26-93.5 × 1.5-3.2 μm. The characters of the Austrian material studied here generally agree well with previous records, and the range of conidial sizes agrees best with that given by Vanev et al. (1997). The authors cited above have listed various names as synonyms of S. lychnidis, including S. lychnidis var. pusilla (= S. pusilla). Two strains isolated from Lychnis cognata in South Korea (CBS 128614, 128630) first also identitifed as S. lychnidis, were shown by sequence analyses to belong to a distinct species, for which the name C. pseudolychnidis is introduced by Quaedvlieg et al. (2013).

Caryophylloseptoria silenes (Westend.) Verkley, Quaedvlieg & Crous, comb. nov. MycoBank MB804471. Fig. 4.

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Fig. 4.

Caryophylloseptoria silenes. A-C. Colonies CBS 109100. A. On OA. B. On CHA. C. On MEA. D. Conidia and conidiogenous cells in planta (CBS H-21160). E. Ibid., on OA (CBS 109100). F-G. Conidia on OA (CBS 109100). Scale bars = 10 μm.

Basionym: Septoria silenes Westend., in Westendorp & Wallays, Herb. crypt. Belge, Fasc. 19, no 955. 1854; Bull. Acad. R. Belg. Cl. Sci., Sér. 2, 2: 575. 1857.

Description in planta: Symptoms leaf spots circular or elliptical, pale yellow to pale brown, surrounded by a dark purplish border; Conidiomata pycnidial, amphigenous but predominately epiphyllous, numerous in each leaf spot, globose to subglobose, immersed, 50-80(-100) μm diam; ostiolum central, initially circular, 20-45 μm wide, later more irregular and up to 50 μm wide, surrounding cells somewhat darker; conidiomatal wall only 10-15 μm thick, composed of textura angularis without distinctly differentiated layers, the outer cells with brown, somewhat thickened walls and 4-7.5 μm diam, the inner cells hyaline and thin-walled and 3.5-5 μm diam; Conidiogenous cells hyaline, ampuliform, or cylindrical and widest near the apex, hyaline, holoblastic, proliferating percurrently 1-several times with distinct scars (annellations), sympodial proliferation not observed, 4-10 × 3-5 μm. Conidia cylindrical, straight or slightly curved, with a rounded apex, lower part attenuated more or less abruptly into a broad truncate base, (0-)1(-4)-septate, somewhat constricted around the septa, hyaline, contents with several oil-droplets in each cell in the living state, with conspicuous oil-droplets and granular contents in the rehydrated state, 21-37 × 2-3.5(-4) μm (rehydrated; in turgescent state up to 4.5 μm wide). Sexual morph unknown.

Description in vitro: Colonies on OA 7-9 mm diam in 12 d (7-10 mm in 3 wk; 21-23 mm in 7 wk), with an even, later undulating, pure yellow to luteous, glabrous margin, the pigment diffusing into the medium around the colony; colonies spreading, but in the centre quite distinctly elevated, immersed mycelium luteous to ochreous-orange, darkened by numerous simple, first brownish, then black pycnidia arranged in concentric patterns, releasing droplets of initally milky white, later pale pure yellow conidial slime; immersed mycelium later mostly luteous to sienna, much darker after 7 wk; most of the colony covered by a high, woolly-floccose mat of pale grey, later straw to pure yellow aerial mycelium; reverse luteous, in the centre umber, ultimately becoming almost black. Colonies on CMA 5-7 mm diam in 12 d (7-9 mm in 3 wk; 18-19 mm in 7 wk), as on OA, but immersed mycelium and (more scarce) aerial mycelium more intensely pigmented, immersed mycelium appearing rust to sienna after 3, but mostly black after 7 wk, and conidial slime earlier pure yellow. Colonies on MEA 3-5 mm diam in 12 d (5-9 mm in 3 wk; 17-20 mm in 7 wk), with a ruffled, yellowish, glabrous margin; diffusing yellow pigment distinct around the colony; colonies restricted, irregularly pustulate up to 3 mm high, the surface dark, blackish or chestnut, covered by a short, dense, almost pruinose mat of grey to pure yellow aerial mycelium; conidiomata releasing droplets of initially pale pure yellow, later almost amber conidial slime; reverse chestnut or blood. Colonies on CHA 3.5-5 mm diam in 12 d (7-8 mm in 3 wk; 12-17 mm in 7 wk), with an even or irregular margin, mostly hidden underneath white aerial hyphae; yellow pigment very clear diffusing beyond the colony margin after 3 wk; colonies restricted, conical or hemispherical, the surface very dark, but mostly covered by a dense mat of woolly, initially white, then pure yellow aerial mycelium; reverse sienna to fulvous. Sporulating scarcely after 3, but more intensely after 7 wk, cirrhi or droplets of pale pure yellow, later amber conidial slime released by superficial conidiomata.

Conidiomata pycnidial, as in planta, but larger, 90-155 μm diam, mostly single, sometimes merged into complexes with several ostioli; conidiogenous cells as in planta, but often with a more elongated neck, proliferating percurrently with distinct annellations or sympodially, 7-17 × 3-5 μm; conidia cylindrical, straight or slightly curved, with a rounded apex, lower part attenuated more or less abruptly into a broad truncate base, (0-)1-3(-4)-septate, somewhat constricted around the septa, hyaline, with several oil-droplets in each cell, (24-)26.5-35(-42) × 3-4(-5) μm.

Hosts: Silene spp.

Material examined: Austria, Tirol, Ötztal, Horlachtal, Mühl near Niederthai, alt. 1500 m, on living leaves of Siline nutans, 3 Aug. 2000, G. Verkley 1041, CBS H-21160, living cultures CBS 109100, 109103.

Notes: Jørstad (1965) examined type material from BR in Westend., Herb. crypt. Belge 955, on Silene armeria. He reported that among numerous immature pycnidia were a few thin-walled pycnidia with 0-septate conidia measuring 21-24 × 2-2.5 μm, but in his opinion there was no doubt that collections from other hosts like Silene cucubalus (= S. inflata), and from Silene rupestris with predominantly 1-septate spores up to 31 μm in length belonged to the same species. In the material collected in Austria, we have observed predominantly 1-septate conidia, but conidial length did vary in different fruitbodies: some pycnidia produced conidia 21-28 μm in length, others conidia measuring 26-37 μm in length. However, isolates from these pycnidia were similar in colony characters and conidia produced did not show such differences in size range.

Priest (2006) noted that there are at least two taxa of Septoria occurring on Silene, a short-spored taxon represented by S. silenes, and a long-spored taxon for which the name S. silenicola applies. This author referred all collections from Australia on this host genus to S. silenicola, for which conidia measure (34-)48-65(-85) × 2-2.5(-3) μm.

As pointed out by Petrak (1925) and Jørstad (1965), several of the Septoria described on Silene spp. (and Melandrium) are likely to be conspecific with S. silenes. Septoria dominii Bubák 1905 was already placed in the synonymy of S. silenes by Jørstad (1965), and the same could be correct for S. dimera from Silene nutans. According to the original diagnosis, the conidia of S. dimera are 1-septate and measure 28-32 × 4 μm. Radulescu et al. (1973) and Markevičius & Treigienė (2003) treated S. dimera as a separate species next to S. silenes, reporting measurements for conidia of S. dimera as 25-40 × 3-4 μm, and 21-35 × 3.2-4.3 μm, respectively. Vanev et al. (1997) also treated S. dimera, reporting conidial measurements 26-65 × 2.5-4 μm, but they included material from Silene spp. and Cucubalus baccifer.

Caryophylloseptoria spergulae (Westend.) Verkley, Quaedvlieg & Crous, comb. nov. MycoBank MB804472. Fig. 5.

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Fig. 5.

Caryophylloseptoria spergulae. A, B. Colonies CBS 109010. A. On OA. B. On MEA. C. Conidia and conidiogenous cells in planta (CBS H-21150). D-H. Conidia on OA (CBS 109010). Scale bars = 10 μm.

Basionym: Septoria spergulae Westend., in Westendorp & Wallays, Herb. crypt. Belge, Fasc. 23-24, no. 1155. 1857; Bull. Acad. R. Belg. Cl. Sci., Sér. 2, 2: 576. 1857.

Description in planta: Symptoms absent. Conidiomata pycnidial, black, in dense groups on dead stems and leaves, only partly immersed in the host tissue, globose or slightly depressed, (50-)75-150 μm diam; ostiolum circular, central, 10-12.5 μm wide, without distinctly differentiated cells; pycnidial wall with an outer layer of textura globulosa-angularis containing cells 8-12 μm diam with brown walls, thickened unevenly up to 3μm, and an inner layer of textura globulosa-angularis containing cells 5-8 μm diam with hyaline or pale brown walls. Conidiogenous cells hyaline, ampuliform, or elongated ampulliform with a distinct neck, hyaline or very pale brown near the base, holoblastic, proliferating percurrently 1-many times with indistinct annellations, also sympodially, 5-10(-16) × 3-5 μm. Conidia cylindrical, regularly curved, or abruptly bent in the lower cell, gradually attenuated to the rounded apex, gradually or more abruptly attenuated into a truncate base, 1(-2)-septate, not or indistinctly constricted around the septum, hyaline, contents rich in small guttulae, minutely granular material and large vacuoles in the living state, oil-droplets merged into larger guttules in the rehydrated state, (18-)24-33 (-40) × 2.0-2.5(-3.0) μm (rehydrated). Sexual morph unknown.

Description in vitro: Colonies on OA less than 2 mm diam after 2 wk (6-8 mm in 28 d), restricted, though not much elevated, with an even, colourless, glabrous margin; colony surface covered by a dense continuous or discontinuous mat of grey, finely felted to somewhat woolly, low aerial mycelium, agar around the colony showing a yellow diffusing pigment; immersed mycelium pale luteous to saffron, reverse concolorous, but olivaceous-black under areas with well-developed aerial mycelium or conidiomata. Colony sporulating in the centre after about 2 wk, with spores in large pale salmon droplets oozing from pycnidioid complexes. Colonies on CMA 8-10 mm diam in 28 d, as on OA, but immersed mycelium soon darkening and olivaceous-black, while the aerial mycelium is somewhat more greenish, and the mat denser and more continuous; reverse olivaceous-black. Colonies on MEA 5 mm diam in 2 wk (8-10 mm in 28 d), restricted, with an even, buff, glabrous margin; colony surface black, but with a diffuse mat of greyish white, often with some sulphur yellow (centre), woolly aerial mycelium; fruitbodies developing tardily on the colony surface, sporulating with large, dirty white to pale reddish masses in watery droplets; reverse dark brick to olivaceous-black. Colonies on CHA 7-9 mm diam in 2 wk, as on MEA, but aerial mycelium higher and denser, in the centre also conspicuously yellowish-pale citrine. No sporulation observed.

Conidiomata mostly olivaceous-brown, irregular merged complexes of initially closed, but soon widely opening stromata, only rarely pycnidial and structurally similar to those on the natural substratum. Conidiogenous cells hyaline, ampuliform, or elongated ampulliform with a relatively long neck, hyaline or very pale brown near the base, holoblastic, proliferating percurrently 1-many times with indistinct annellations, also sympodially, mostly after one or more percurrent proliferations, 7-14(-22) × 3-5 μm. Conidia on OA hyaline, pale salmon in mass, cylindrical and regularly curved, or abruptly bent in the lower or upper cell, gradually attenuated to the rounded apex, more abruptly attenuated into a truncate base, contents granular with large vacuoles, 1(-3)-septate, not or indistinctly constricted around the septa, contents rich in minute guttulae and granular material, 25.5-41 × (2.0-)2.5-3.0(-4.5) μm.

Hosts: On dead leaves and stems of Spergula spp.

Material examined: Belgium, Beverloo, on dry leaves and stems of Spergula arvensis, M. Torquinet s.n., isotype BR-MYCO 159328-54, also distributed in Westendorp & Wallay, Herb.crypt.Belg., Fasc. 23-24: no.1155. Germany, Brandenburg, Kreis Nieder-Barnim, near Prenden, on leaves and stems of Spergula vernalis, 24 July 1920, H. & P. Sydow s.n., distributed in Sydow, Mycotheca germanica 1688, CBS H-4765. Netherlands, on Dianthus caryophyllus, Schouten s.n., CBS 397.52 (sub S. dianthi Desm.); Prov. Gelderland, ‘t Harde, Doornspijkse Heide, De Zanden, on decaying leaves of Spergula morisonii, A. Aptroot 48300, 13 June 2000, epitype designated here CBS H-21150 “MBT175350”, living culture ex-epitype CBS 109010.

Notes: This fungus was originally described from dry leaves and stems of Spergula arvensis by Westendorp, who described the conidia as 30 × 2.5 μm. The type from BR is well-preserved and rich in fruitbodies on leaves and stems, where conidia are 1(-2)-septate, 20-38 × 2-2.5(-3) μm. The collection Aptroot 48300 from Spergula morisonii agrees in morphology and can be identified as conspecific, although it contains a larger proportion of 2-septate conidia (that are mostly 30-40 μm long) than in the type. The material on Spergula vernalis that was distributed as Mycotheca germanica 1688 morphologically also agrees with these collections.

Other names were later introduced for Septoria on members of the plant genus Spergularia (= Alsine), which is closely related to Spergula: S. alsines Rostr. 1903 from Spergularia sp., conidia 20-31 × 2-3 μm formed in 55-120 μm wide pycnidia (Teterevnikova-Babayan 1987; conidia 20-25 × 2-3 μm and 3-septate, in the original diagnosis of Rostrup 1903, based on material from Alsine verna non Spergula vernalis), S. spergulariae 1903, on Spergularia rubra (conidia 30-45 × 2.5-3 μm, “multiseptate”), S. vandasii 1906, on Alsine glomerata, and S. spergularina 1945, on Spergularia longipes (no conidial measurements available). Some of these names could be synonymous with S. spergulae or perhaps S. alsines, but in order to corroborate this, new material needs to be collected and compared to the types. According to Teterevnikova-Babayan (1987), S. alsines differs from S. spergulae in conidial shape in that the conidial base is more truncate than in S. spergulae, and in that it is capable of also killing Minuartia glomerata. Rhabdospora alsines Mont. 1892, which was described from dead stems of Alsine tenuifolia, is unlikely to be conspecific with S. spergulae, as its conidia were described as 16-18 × 2 μm and 1-septate.

Muthumary (1999) studied type material of S. dianthi 1849 (PC 344) and by the drawings he made of it the conidia of this fungus and those of S. spergulae appear very similar in shape. Muthumary reported that the conidia of S. dianthi were 32-48 (av. 40) × 3-4 (av. 3) μm, and mostly 1-, rarely 2-septate. Given these measurements, on average, the conidia in the type of S. dianthi are clearly longer than in S. spergulae (on average below or around 30). Moreover, S. dianthi is a fungus causing leaf spots on several Dianthus spp., while S. spergulae is only known from dry and dead host tissues, and is therefore believed to be saprobic (and possibly endophytic). CBS 109010 and the only strain available for S. dianthi (CBS 397.52) show 100 % sequence homology of the LSU, ITS, Btub and Cal, while there are only minor differences in Act (99.25 %), EF (97.54 %), and RPB2 (99.42 %). Further work is required to establish that S. dianthi and S. spergulae are truely distinct taxa.

Septoria Sacc., Syll. Fung. 3: 474. 1884. nom. cons.

Type species: S. cytisi Desm.

A generic description is provided by Quaedvlieg et al. (2013, this volume).

Septoria aegopodii Desm. ex J. Kickx, Pl. Crypt. Fland. 1: 427. 1876 [Annls Sci. Nat., sér. 6, 7: no 616. 1878?]. Fig. 6.

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Fig. 6.

Septoria aegopodii. A-E. Conidia in planta. A-C. CBS H-21262. D, E. CBS H-21199. Scale bars = 10 μm.

• = Septoria podagrariae Lasch, in Rabenh., Herb. mycol. I, no 458. 1843. nomen nudum.

• = Sphaeria podagrariae Roth, Catal. Bot. 1: 230. 1797.

  • ≡ Mycosphaerella podagrariae (Roth: Fr.) Petr., Annls mycol. 19 (3/4): 203. 1921.

• = Cryptosporium aegopodii Preuss, Linnaea 24: 719 (Fungi Hoyersw., no. 322). 1853.

  • ≡ Phloeospora aegopodii (Preuss) Grove, British Stem- and Leaf-fungi (Coelomycetes) 1: 434. 1935.

  • ≡ Septoria aegopodii (Preuss) Sacc., Syll. Fung. 3: 529. 1884 [non Desm. 1878].

• ?= Septoria podagrariae var. pimpinellae-magnae Kabát & Bubák, in Bubák & Kabát, Ber. naturw.-med. Ver. Innsbruck 30: 19-36 (extr. 11). 1906.

• = Mycosphaerella aegopodii Potebnia, Annls mycol. 8(1): 49. 1910.

Description in planta: Symptoms leaf spots numerous but small, angular and delimited by veinlets, visible on both sides of the leaf, white to pale yellow. Conidiomata pycnidial, developing soon after first discolouration of the host tissue, predominantly epiphyllous, mostly also visible from the underside of the lesion, several scattered in each leaf spot, globose to subglobose, pale to dark brown (drying black), immersed, 125-190 μm diam, releasing conidia in white cirrhi; ostiolum central, initially circular and 17-35 μm wide, later becoming more irregular and up to 100 μm wide, surrounding cells dark brown, with thickened cell walls; conidiomatal wall except for the part surrounding the ostiolum poorly developed, about 10-20 μm thick, composed of pale brown to hyaline angular cells 3.5-8 μm diam with thin walls. Conidiogenous cells hyaline, discrete, cylindrical to narrowly or broadly ampulliform, holoblastic, proliferating sympodially, 8-15(-18) × 2.5-4.5 μm. Conidia filiform-cylindrical, straight, curved to somewhat flexuous, attenuated gradually to a relatively broadly rounded apex and broadly truncate base often provided with a collar of gelatinous material, (0-)1-2(-3)-septate (second and later septa very thin and easily overlooked), not constricted around the septa, hyaline, contents with numerous minute oil-droplets and granular material in each cell in the living state, with minute oil-droplets and granular contents in the rehydrated state, (30-)55-95(-115) × 3.5-4 μm (living; 30-72(-80) × 2.5-4 μm, rehydrated).

Description in vitro: All attempts to grow the isolates from conidia failed. Some conidia germinated at the apical cells, but mycelia died within 1-2 d after germination.

Hosts: Aegopodium podagraria and Pimpinella sp.

Material examined: Austria, Tirol, Ötztal, Ötz near Habichen, on living leaves of Pimpinella sp., 24 July 2000, G. Verkley 1001, CBS H-21187. Netherlands, Prov. Overijssel, Losser, in garden at Mollenbergstraat, on living leaves of Aegopodium podagraria, June 1999, G. Verkley 800, CBS H-21192; same substr., Prov. Overijssel, Losser, Arboretum Poort-Bulten, June 1999, G. Verkley 801, CBS H-21193; same substr., Prov. Utrecht, ‘s Graveland, Gooilust, 5 Sep. 1999, G. Verkley 916, CBS H-21199; same substr., Prov. Limburg, St. Jansberg, near Plasmolen, 9 Sep. 1999, G. Verkley 931, CBS H-21211; same substr., Prov. Zeeland, Zuid-Beveland, Community of Borsele, Schouwersweel near Nisse, 27 Aug. 2001, G. Verkley 1116, CBS H-21165; same substr., Prov. Utrecht, Soest, 29 July 2008, G. Verkley 5020, CBS H-21262.

Notes: This species is common on Aegopodium podagraria, especially on plants growing under less favourable conditions. Jørstad (1965) noted that in autumn the pycnidia are commonly accompanied by immature perithecia (or by “sclerotia”) of Mycosphaerella aegopodii in Sweden, but we have not found any in The Netherlands. According to van der Aa (pers. comm.), the sexual morph only matures in montane habitats. Aptroot (2006), who studied herbarium specimens collected at high altitudes in several localities in Europe also did not observe any mature ascomata. Type material of M. podagrariae could not be located (Aptroot 2006). Simon et al. (2009) studied the cellular interactions between M. podagrariae and Aegopodium podagraria based on German material (no cultures preserved).

We have not seen the type of S. podagrariae var. pimpinellae-magnae 1906 described from Pimpinella magna (= P. major?) in Tirol, but since the conidial characters given by Saccardo & Trotter (1913, 45-60 × 2.5-4 μm, 3-septate) are well within the range of S. aegopodii, it is placed here tentatively as a synonym. On Pimpinella, eight other Septoria species or varieties have been described in the literature, but these could not be studied here. The oldest available name would be S. pimpinellae Ellis 1893 (later homonyms Laubert 1920 and Hollós 1926). According to the diagnoses the conidial sizes described for these taxa largely overlap, and range from 15-35 × 1-1.5(-2) μm, thus all considerably smaller than in S. aegopodii.

Septoria aegopodina Sacc., Michelia 1: 185. 1878. Fig. 7.

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Fig. 7.

Septoria aegopodina. A, B. Colonies CBS 123740. A. On OA. B. On MEA. C-F. Conidia in planta (CBS H-21249). G. Conidia and conidiogenous cells in planta (CBS H-21249). H, I. Conidia on OA (CBS 123741). J. Conidia on MEA (CBS 123740). Scale bars = 10 μm.

• = Septoria aegopodina var. villosa Gonz. Frag., Assoc. españ. Progr. Cienc. Congr. Oporto, 6. Cienc. natur.: 47. 1921.

• = Septoria aegopodina var. trailii Grove, British Stem-and Leaf-Fungi (Coelomycetes) 1: 396. 1935.

Description in planta: Symptoms leaf spots numerous, indefinite and soon covering large parts of the leaf lamina, visible on both sides of the leaf, first yellow then pale orange-brown. Conidiomata pycnidial, predominantly hypophyllous, scattered or gregarious, globose to subglobose, pale to dark brown, immersed, 90-160 μm diam, releasing conidia in white cirrhi; ostiolum central, circular and 15-25 μm wide, surrounded by cells with dark brown to almost black, thickened walls; conidiomatal wall 10-28 μm thick, composed of an outer cell layer of pale brown to hyaline isodiametric angular or globose cells, 3.5-8 μm diam with thickened walls, and an inner layer of one or more hyaline cells with not or only slightly thickened walls. Conidiogenous cells hyaline, discrete, mostly broadly ampulliform, holoblastic, rarely proliferating sympodially, possibly also percurrently but no annellations visible, 4-7(-8) × 3-4.5 μm. Conidia filiform to filiform-cylindrical, straight or curved, attenuated gradually to a narrowly rounded to somewhat pointed apex, and attenuated gradually or more abruptly to a narrowly truncate base, (0-)1-3-septate, not constricted around the septa, hyaline, with numerous minute and several larger oil-droplets in each cell in the living state, and minute oil-droplets and granular contents in the rehydrated state, (22-)30-42.5 × 1.5-2(-2.5) μm (rehydrated). Sexual morph unknown.

Description in vitro (20 °C, diffuse daylight): Colonies on OA 7-10 mm diam in 2 wk, with a very narrow, glabrous and rosy-buff margin; colony restricted, somewhat elevated, immersed mycelium colourless to faintly brick, or much darker, brown-vinaceous, but mostly hidden under a dense, woolly mat of pure white to faintly yellow aerial mycelium; reverse olivaceous-black to dark brick; a vinaceous pigment diffusing into the surrounding medium. Colonies on MEA 8-15 mm diam in 2 wk, the margin covered by pure white aerial hyphae; colony restricted, irregularly postulate in the central area, mostly covered by a dense woolly-floccose mat of smoke grey aerial mycelium, but after 2 wk numerous glabrous, black conidiomata appear on the colony surface in the centre, releasing milky white conidial slime. Reverse of colony olivaceous-black.

Conidia on MEA elongated ellipsoidal to cylindrical, straight to distinctly curved, rounded to narrowly pointed at the apex, attenuated gradually to a narrowly truncate base, 0-1-septate, 0-septate 8-12 × 2-2.5(-3), 1-septate 10-21 × 2-2.5 μm; Conidia on OA cylindrical, straight or slightly to distinctly curved, narrowly rounded to slightly pointed at the apex, attenuated gradually to a narrowly truncate base, 1-3-septate, (16-)20-32 × 1.5-2 μm.

Hosts: Aegopodium podagraria and Pimpinella spp.

Material examined: Czech Republic, Moravia, Veltice, Forest of Rendez Vous, on living leaves of Aegopodium podagraria, 16 Sep. 2008, G. Verkley 6013, CBS H-21249, living cultures CBS 123740, 123741.

Notes: Morphologically, the material from the Czech Republic available here agrees well with S. aegopodina as described by Vanev et al. (1997) and Shin & Sameva (2004), although the pycnidia are larger than described by these authors (55-85 μm diam). The species can easily be distinguished from S. aegopodii occurring on the same host plant, as the conidia of that fungus are considerably larger (30-115 × 3.5-4 μm), and appear predominantly 1-septate. The conidia more closely resemble those of S. anthrisci. The diagnoses of S. aegopodina var. trailii based on material on Pimpinella saxifraga, and of S. aegopodina var. villosa on Pimpinella villosa, agree with the description of the type variety. Both varieties are therefore considered synonyms of S. aegopodina. In the multigene phylogeny S. aegopodina groups fairly closely with S. oenanthicola, S. sii and S. oenanthis from the same host family (Apiaceae), but other taxa from that family like S. anthrisci are relative distant and belong elsewhere the Septoria clade (Fig. 2). Other isolates grouping with S. aegopodii include those of S. mazi from Mazus japonicus (Scrophulariaceae), S. campanulae from Campanula takesimana (Campanulaceae), and S. gentianae from Gentiana scabra var. buergeri (Gentianaceae).

Septoria anthrisci Pass. & Brunaud, Rev. Mycol. (Toulouse) 5: 250. 1883 [non P. Karst., Meddn Soc. Fauna Flora fenn. 13: 10. 1884]. Fig. 8.

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Fig. 8.

Septoria anthrisci. A. Conidia and conidiogenous cells in planta (CBS H-21185). B. Conidia on OA (CBS 109020). Scale bars = 10 μm.

Description in planta: Symptoms leaf spots numerous but small, circular to elliptical, visible on both sides of the leaf, the centre white to pale ochreous, surrounded by a relatively narrow, somewhat elevated, dark reddish brown to black margin. Conidiomata pycnidial, epiphyllous, sometimes also visible from the underside of the lesion, mostly one, rarely up to three in each leaf spot, subglobose to lenticular, sometimes becoming cupulate, brown to black, immersed, 115-190 μm diam; ostiolum central, initially circular and 30-55 μm wide, later becoming more irregular and up to 100 μm wide, surrounding cells concolorous; conidiomatal wall about 12-20 μm thick, composed of an outer layer of pale brown angular cells 4.5-7 μm diam with somewhat thickened walls, and an inner layer of thin-walled, pale yellow angular to globose cells 2.5-5 μm diam. Conidiogenous cells hyaline, discrete, rarely integrated in 1-septate conidiophores, globose or narrowly or broadly ampulliform, holoblastic, mostly with a relatively narrow elongated neck, proliferating percurrently several times with distinct annellations, often also sympodially after or in between a few percurrent proliferations, 6-14(-18) × 2.5-5(-6) μm. Conidia filiform, straight, curved to flexuous, attenuated gradually to a narrowly pointed apex and narrowly truncate base, (0-)1-3(-4)-septate (septa very thin and easily overlooked), not constricted around the septa, hyaline, contents with several minute oil-droplets and granular material in each cell in the living state, with minute oil-droplets and granular contents in the rehydrated state, (18-)25-59 (-65) × 1-2 μm (living; rehydrated, 1-1.8 μm wide). Sexual morph unknown.

Description in vitro: Colonies on OA 4-6(-9) mm diam in 1 wk (18-22 mm in 22 d), with an even, glabrous, peach, later coral margin, with a concolorous pigment diffusing beyond the colony margin; colonies after 1 wk restricted, distinctly elevated in the centre, immersed mycelium first peach to pale coral, then deep coral, the colony already appearing darker in the centre after 1 wk due to numerous almost black pycnidial conidiomata in part merging into large complexes, releasing pale whitish or rosy-buff droplets of conidial slime from one to several short-papillate or more elongated neck-like openings; reverse in the centre blood colour, surrounded by a first intense peach, later scarlet or coral area. Colonies on CMA 7-8(-9) mm diam in 1 wk (18-21 mm in 22 d), as on OA. Colonies on MEA 6-11 mm diam in 1 wk (24-29 mm in 22 d), with an even, almost glabrous, buff margin, without a diffusing pigment; colonies restricted, irregularly pustulate to hemispherical, already up to 4 mm high after 1 wk, immersed mycelium leaden grey to olivaceous-grey, covered by well-developed white to greyish, appressed, woolly aerial mycelium; conidiomata abundantly developing at the surface in the central area, releasing cirrhi of buff to pale luteous to rosy-buff conidial slime; reverse fuscous black to brown-vinaceous, surrounded by a narrow pale luteous marginal zone. Colonies on CHA 7-12 mm diam in 1 wk (29-31 mm in 22 d), as on MEA, but the surface more glaucous to glaucous blue green, the margin rosy-buff, and the conidial slime pale flesh.

Conidiomata pycnidial, single, brown to black, 100-250 μm diam, conidiogenous cells as in planta; conidia as in planta, 25-55(-69) × 1.2-2 μm.

Hosts: Anthriscus spp., and also Chaerophyllum spp. (Teterevnikova-Babayan 1987; Vanev et al. 1997).

Material examined: Austria, Tirol, Ötztal, Sautens, on living leaves of Anthriscus sp., 30 July 2000, G. Verkley 1022, CBS H-21185, living culture CBS 109019, 109020.

Notes: According to the short and incomplete original diagnosis, the conidia of S. anthrisci are continuous, 40-50 μm long. The type host is Anthriscus vulgaris. The description of the species on the host agrees well with those provided by Vanev et al. (1997) and Teterevnikova-Babayan (1987), although the latter reported conidia up to 75 μm long. The species is close to S. petroselini (CBS 182.44 and CBS 109521), from which it cannot be distinguished by ITS sequence, but the EF and Act sequences proved to differ by 4 and 27 %, respectively.

Of other Septoria species found on the family Apiaceae, only S. petroselini is relatively closely related. Septoria petroselini can be distinguished from S. anthrisci by the larger conidia (29-80 × 1.9-2.5 mm) with up to 7 septa on the host plant, usually species of Petroselinum or Coriandrum.

Septoria apiicola Speg., Boln Acad. nac. Cienc. Córdoba 11: 294. 1888. Fig. 9.

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Fig. 9.

Septoria apiicola. a. Colony on OA (CBS 400.54). B, C. Conidia in planta (CBS H-21261). D. Conidia on OA (CBS 400.54). E. Conidia and conidiogenous cells on OA (CBS 400.54). F. Ibid., in planta (CBS H-21261). Scale bars = 10 μm.