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Damm et al.Fig. 17. Colletotrichum torulosum. A–B. Conidiomata. C. Setae. D–F. Conidiophores. G. Seta. H. Conidiophores. I–N. Appressoria. O–P. Conidia. A–B, D–P. from ex-holotypestrain CBS 128544. C. from strain CBS 102667. A, C–F, O. from Anthriscus stem. B, G–N, P. from SNA. A–B. DM, C–P. DIC, Scale bars: A = 100 µm, D = 10 µm. Scale barof A applies to A–B. Scale bar of D applies to C–P.Pai (1970) regarded C. heveae Petch as the anamorph of G.phyllanthi on the basis of the telemorph strain being pathogenic tofour of six Euphorbiaceae plant species tested, including Heveabrasiliensis, along with general morphological similarity. Theconidium size of C. heveae was given as 18–24 × 7.5–8 µm byPetch (1906), wrongly cited by Pai (1970) as 18–24 × 5–8 µm.Type material of Colletotrichum heveae (Sri Lanka, on Hevea,7 Oct. 1905, Petch 2228, K(M) 167287) is in poor condition with theColletotrichum colonies overrun by saprobic species. The packetindicates that two species are present, Gloeosporium brunneumand C. heveae. Apart from the saprobic fungi the only species nowpresent is a Colletotrichum-like fungus that lacks setae, but withrather variable ± cylindrical conidia with rounded ends that aremostly 14.5–16 × 4–6 µm in size. These are wider than typical C.gloeosporioides conidia and are reminiscent in some features ofthe C. boninense aggregate, so it is possible that the anamorphteleomorphconnection assumed by Pai (1970) is correct. However,there are no authentic cultures of C. heveae and the type materialis in a poor state. Gloeosporium brunneum Ellis & Everh. isconsidered to be the anamorph of Drepanopeziza punctiformisGremmen (von Arx 1970), a north temperate pathogen of Populusand most unlikely to be present on a Hevea leaf from Sri Lanka.Use of that name by Petch remains a mystery. According to anote in the CBS database von Arx did not support the teleomorph/anamorph connection assumed by Pai (1970), and we can see noclear reason why the two taxa should be linked in this way.Diseases of Hevea in south India caused by Colletotrichumspecies are attributable to the C. gloeosporioides and C. acutatumaggregates (e.g. Saha et al. 2002; unpublished ITS sequences fromthis research deposited in GenBank confirm these identificationsto species aggregate level). A species on Hevea from Colombiaclosely related to C. phyllanthi is described in this paper (see C.annellatum).Colletotrichum torulosum Damm, P.F. Cannon, Crous, P.R.Johnst. & B. Weir, sp. nov. MycoBank MB560747. Fig. 17.Etymology: Named in recognition of the highly convoluted natureof its appressoria.Anamorph on SNA. Vegetative hyphae 1–7.5 µm diam, hyaline,smooth-walled, septate, branched. Chlamydospores not observed.Conidiomata absent and conidiophores and setae formeddirectly from hyphae. Setae medium brown, basal cell paler,verruculose, 2–5-septate, 65–120 µm long, sometimes branched,base cylindrical, 3.5–5.5 µm diam, tip ± acute to ±rounded.Conidiophores hyaline, smooth-walled, septate, branched, to 75µm long. Conidiogenous cells hyaline, smooth-walled, cylindrical,8–23 × 3.5–5.5 µm, opening 1–2 µm diam, collarette ≤ 0.5 µmdiam, periclinal thickening conspicuous. Conidia hyaline, smoothwalled,aseptate, cylindrical, the apex and base rounded, with aprominent scar and an apparently verrucose vesicle attached to32
The Colletotrichum boninense species complexit, contents granular, (13–)14–17(–21) × 5.5–6.5(–7.5) µm, mean± SD = 15.5 ± 1.5 × 6.0 ± 0.4 µm, L/W ratio = 2.6, conidia ofstrain CBS 102667 are shorter, measuring (10.5–)12–14.5(–17.5)× (4.5–)5.5–6.5 µm, mean ± SD = 13.4 ± 1.2 × 5.8 ± 0.5 µm, L/Wratio = 2.3. Appressoria medium to dark brown, outline variable,the margin lobate, single or in loose groups, (5.5–)8.5–14.5(–16.5)× (4.5–)6–9.5(–13) µm, mean ± SD = 11.4 ± 2.9 × 7.7 ± 1.9 µm,L/W ratio = 1.5.Anamorph on Anthriscus stem. Conidiomata acervular,conidiophores formed on a cushion of pale brown, angularcells, 3–10 µm diam. Setae not observed in strain CBS 128544.Setae of strain CBS 102667 medium brown, basal cell paler,verruculose, sometimes verrucose, 0–2-septate, 20–60 µm long,base cylindrical, conical or slightly inflated, 4.5–6.5 µm diam, tiprounded. Conidiophores hyaline to pale brown, smooth-walled,septate, branched, to 60 µm long. Conidiogenous cells hyalineto pale brown, smooth-walled, cylindrical, often extending to formnew conidiogenous loci, 9–23 × 4.5–6.5 µm, opening 1.5–2.5 µmdiam, collarette ≤ 0.5 µm diam, periclinal thickening conspicuous.Conidia hyaline, smooth-walled, aseptate, cylindrical, the apex andbase rounded, with a prominent scar, contents guttulate, (13.5–)14.5–16.5(–17.5) × (5–)5.5–6(–6.5) µm, mean ± SD = 15.5 ± 0.9× 5.8 ± 0.3 µm, L/W ratio = 2.7, conidia of strain CBS 102667 areshorter, measuring 12–14.5(–18) × (5–)5.5–6(–6.5) µm, mean ±SD = 13.4 ± 1.3 × 5.7 ± 0.4 µm, L/W ratio = 2.3.Material examined: New Zealand, GB, Gisborne, Allen Park Gardens, from Solanummelongena (eggplant), 6 Mar. 1990, P.R. Johnston, (CBS H-20715 holotype,culture ex-type CBS 128544 = ICMP18586); Auckland, Mount Albert, from leaf blochof Passiflora edulis, May 2000, C.F. Hill, CBS H-20716, culture CBS 102667.Notes: Colletotrichum torulosum occupies a minor clade as sister toa group containing C. boninense s. str. and an unnamed taxon thatoccurs on orchids (CBS 123921). It has significantly longer conidiathan C. boninense with a larger L/W ratio. The conidia formed onSNA have hyaline, faintly verrucose vesicles attached to the baseadjacent to the conidial scar. The function of these structures isunclear and they may be artefacts. These vesicles also occur onconidia of C. cymbidiicola (Fig. 9R).Colletotrichum torulosum is known from two New Zealandcollections, on Solanum and Passiflora. Endophytic strains fromDacrycarpus dacrydioides (Podocarpaceae) and Kunzea ericoides(Myrtaceae) leaves from New Zealand have the same ITSsequences as C. torulosum (EU482212, EU482213; Joshee et al.2009), although their identity needs to be confirmed by comparisonwith sequences of other genes. Colletotrichum torulosum is nothost-specific. It is not clear whether it is a native New Zealandspecies that has jumped onto cultivated exotic plants, or has beenimported on diseased plant material.DISCUSSIONMoriwaki et al. (2003) differentiated C. boninense from C.gloeosporioides based on its wider conidia (L/W ratio = (1.8–)2–3(–3.3), the prominent scar at the conidial base and cream to orangecoloured colonies on PDA. The L/W ratio of conidia of C. boninenses. str. and C. karstii (included in C. boninense by Moriwaki et al.2003) are variable, ranging from 2.1 to 2.8 depending on isolate(and medium), while conidia of C. gloeosporioides have a L/Wratio of 2.6 to 3.0 (Cannon et al. 2008, Weir et al. 2012). Accordingto Moriwaki et al. (2003), the shape of the appressoria in C.boninense differs from that seen in C. gloeosporioides, and setaeare rarely produced in C. boninense. Many strains belonging tothe C. boninense aggregate have more complex appressoria thanthose typical for C. gloeosporioides.None of the morphological characters of C. boninenseenables unequivocal identification and misplacement of strainsbased on morphology alone is common. For example, Lu et al.(2004) classified one isolate as C. gloeosporioides accordingto morphological characters but re-identified it as C. boninenseusing molecular techniques. Colletotrichum dracaenae Petch(here epitypified and renamed as C. petchii) was considered as asynonym of C. gloeosporioides by von Arx (1957). Our study showsthat C. petchii does not belong to C. gloeosporioides s. lat., but tothe C. boninense species complex, although the conidia are largelytypical of C. gloeosporioides with their relatively large length/widthratio.Conidiogenesis in the C. gloeosporioides and C. boninensespecies complexes is usually percurrent, but more variablein C. boninense, depending on the site of septation in theconidiogenous cell that results in a prominent periclinal thickening.Sometimes distinct annellations are formed, which are commonin C. annelatum and occasionally occur in C. dacrycarpi and C.petchii. After producing a number of conidia the conidiogenouscells of many species extend without forming a septum andform a new conidiogenous locus at the tip. These processes canalternate, making the conidiogenous cell appear catenate, e.g. inC. constrictum, C. novae-zelandiae and C. oncidii. Additionally,several species had an apparent gelatinous multi-layered coatingaround the conidiogenous cells.Differentiation between the two species complexes usingmorphological methods is problematic, but the diagnostic charactersestablished by Morikawi et al. (2003) can be used reliably to identifymany isolates. A distinctive feature of the C. boninense complexin morphological terms is the conidiogenous cell with prominentpericlinal thickening that extends to form a new conidiogenouslocus. This feature is unknown in species of the C. gloeosporioidescomplex (Weir et al. 2012). Another distinctive feature of the C.boninense complex is the prominent scar (hilum) at the base ofthe conidia.Species of the C. boninense complex appear to be concentratedin certain regions of the world, and prefer certain host plants. Isolatestreated in this paper and found by nucleotide blastn searches ofGenBank originate mainly from New Zealand/Australia, South andEast Asia (Japan, China, Taiwan, Thailand, Vietnam, India), Southand Central America (Columbia, Brazil, Panama, Mexico, Guyana)and South and East Africa (South Africa, Zimbabwe, Kenya). Anumber of isolates from Europe (Italy, Netherlands, Germany andprobably Hungary) have been associated with indoor/greenhouseplants (Dracaena, Hippeastrum and Gossypium species andseveral orchids) or air from greenhouses with orchids (Magyar etal. 2011). A few samples from Coffee arabica and Leucospermumoriginated from U.S.A. (Hawaii) and one from Protea obtusifoliafrom Madeira (Portugal).Four of the species in the C. boninense complex have only beenfound in New Zealand (two on indigenous plants), and three onlyfrom Colombia or Brazil (two of these from Passiflora). The speciesrichness in New Zealand is surprising as no Colletotrichum taxonhas previously been described from this country, apart from theformae speciales C. acutatum f. sp. pineum and C. gloeosporioidesf. sp. camelliae. Compared with many countries, plant biosecurityis well supported in New Zealand, and both exotic and indigenousspecies are likely to be surveyed more intensively for pathogenswww.studiesinmycology.org33
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The Colletotrichum acutatum species
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Damm et al.µm diam. Setae not obse
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Damm et al.Table 2. Conidia measure
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Damm et al.Table 2. (Continued).Spe
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Damm et al.Table 3. Appressoria mea
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Damm et al.Fig. 25. Colletotrichum
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Damm et al.to olivaceous grey, filt
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Damm et al.are formed directly from
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Damm et al.Arx JA von (1957). Die A
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Damm et al.Masaba DM, Waller JM (19
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114
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Weir et al.grass-inhabiting species
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Weir et al.Table 1. A list of strai
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Weir et al.Table 1. (Continued).Spe
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Weir et al.Table 1. (Continued).Spe
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Weir et al.Table 2. Primers used in
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Weir et al.11ICMP 17789 Malus USA1I
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Weir et al.Kahawae cladeC. alataeC.
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Weir et al.A0.991ICMP 17905 Coffea
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Weir et al.Conidial width variation
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Weir et al.G. c.“f.sp. camelliae
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Weir et al.Fig. 10. Colletotrichum
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Weir et al.Fig. 18. Glomerella cing
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Weir et al.images under C. fructico
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Weir et al.Specimen examined: Thail
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Weir et al.Notes: First described f
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Weir et al.gossypii var. cephalospo
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Weir et al.to utilise either citrat
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Weir et al.(ex-epitype culture CBS
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Weir et al.of this species to C. ps
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Weir et al.Table 4. Performance of
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Weir et al.Crous PW, Gams W, Stalpe
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Weir et al.Simmonds JH (1968). Type
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Cannon et al.182
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Cannon et al.In rare instances, Col
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Cannon et al.Table 1. Summary of pr
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Cannon et al.Table 1. (Continued).P
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Cannon et al.Table 2. Colletotrichu
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Cannon et al.as did those for Colle
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Cannon et al.Table 3. Authentic seq
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Cannon et al.Table 3. (Continued).S
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Cannon et al.110.74 C. cuscutae IMI
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Cannon et al.Boninense cladeThe bon
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Cannon et al.C. lindemuthianum AB08
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Cannon et al.A further important ac
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Cannon et al.Hawksworth DL (2011).
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Cannon et al.Rodríguez-Guerra R, R
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Studies in MycologyStudies in Mycol
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CBS Biodiversity SeriesNo. 11:Taxon
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Studies in Mycology (ISSN 0166-0616
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