Introduction

The Iberian Peninsula is considered one of the most important European reservoirs of biodiversity. Its rich vegetation and varied climatic regimes favour the development of a great mycobiota diversity. However, microfungi, especially anamorphic fungi, are poorly known from this region. During a survey of microfungi associate with plant debris in natural areas of Spain four interesting anamorphic fungi belonging to the genus Diplococcium Grove were found.

Species of Diplococcium are characterized by the production of simple or branched catenate conidia, originating from polytretic conidiogenous cells, mostly branched but also simple conidiophores are present in some species. The genus Diplococcium is morphologically similar to Spadicoides Hughes, conidial catenation being the only character for separating the genera (Goh and Hyde 1998). Although more than thirty species of Diplococcium have been described, up to now only 24 are currently accepted in the genus (Braun et al. 1996, Goh and Hyde 1998, Wang and Sutton 1998, Cruz et al. 2007). Two of these species, i.e. D. stoveri (M.B. Ellis) R.C. Sinclair, Eicker & Bhat and D. hugesii Wang & Sutton, have been reported respectively with a phialidic synanamorph (Shirouzu and Harada 2008) or a Selenosporella synanamorph (Wang and Sutton 1998).

Diplococcium has been associated to Helminthosphaeria Fuckel, a member of Helminthosphaeriaceae (Sordariales, Sordariomycetes) (Subramanian 1983; Samuels et al. 1997; Goh and Hyde 1998), and to Otthia pulneyensis Subram. & Sekar, a member of Botryosphaeriaceae (Botryosphaeriales, Dothideomycetes), but only in the last species anamorph-teleomorph connection has been established on single-spore culture (Subramanian and Sekar 1987). Recent molecular data demonstrated that Diplococcium is a polyphyletic genus, with some members related to Dothideomycetes and others to Leotiomycetes (Shenoy et al. 2007, 2010).

The combined morphological features observed in three of the fungi found in the Spanish localities do not fit any of the currently known Diplococcium species and are, therefore, described here as new. The fourth specimen was identified as D. pulneyense Subram. & Sekar, an anamorph only described in vitro.

Materials and methods

Site and sample procedure

Plant specimens were collected from two areas of the north of Spain, i.e. the Picos de Europa National Park located in Asturias, and the Ordesa y Monte Perdido National Park located in the Aragon Pyrenees. Additional collections were also made at the eastern end of the peninsula in Valencia Province.

In the first locality, the park covers an area of 65,000 ha. The relief is very uneven, with big altitude differences and peaks substantially higher than 2,000 m, like Torre Cerredo (2,648 m). Weather conditions are characterized by high humidity and heavy cloud cover. The average temperature in the area varies from 15°C in July and just 3°C in January. The Picos de Europa receives plentiful snowfalls between November and February. Precipitation varies between 1,000 and 1,500 mm. The vegetation type is Atlantic forest, composed of chestnut, holm oak and, especially, beech.

The Ordesa y Monte Perdido National Park was recognized in 1997 as a world heritage site. The park covers an area of 15,608 ha and comprises four deep valleys or canyons: Añisclo, Bujaruelo, Escuaín and Pineta. The forest is distributed from 750 to 2,100 m in altitude, with Mediterranean, montane, oro-Mediterranean and subalpine biotic zones (Villar & Benito-Alonso 2006). Average temperature varies from 0.4–0.7°C in the coldest months (January and February), to 13°C in the warmest (July and August) and average annual rainfall is an estimated 1,735 mm. The vegetation comprises mainly oaks, pines, hazel and beech trees.

In Valencia, collecting was carried out in northwest part of the Province in the Chera-Sot Natural Park. The park, which covers 6,451 ha, is very rugged and mountainous, with Chera itself located within a rift valley surrounded by peaks rising to 1,100m. It has a Mediterranean climate. The forest area was reduced by fire in the 90s. At present, traces of pine trees can be found in Roden and Aleppo. The holm oak forests, which previously constituted the predominant vegetation, remains in forests of Quercus rotundifolia and Quercus faginea.

Plant material was collected, put into polyethylene bags, and kept at 4–7°C until they were examined.

Isolation and identification of fungi

Plant debris were placed into moist chambers, incubated at room temperature (ca. 20°C) and examined periodically under the stereomicroscope for a 2-month period. Semipermanent and permanent microscope slides of fungi growing on the natural substratum were mounted in lactic acid 85% or alcohol polyvinyl and examined under light microscope for identification. To get pure cultures, conidia were transferred from the natural substratum to two different media: potato carrot agar (PCA: 20 g potatoes, 20 g carrots, 20 g agar, 1 L distilled water) and oat-meal agar (OA: 30 g oat flakes, 20 g agar, 1 L distilled water) and incubated at 25°C in the dark. Colour notations in parentheses are from Kornerup & Wanscher (1984). Photomicrographs were obtained with a Zeiss AXIO Imager M1 light microscope (Göttingen, Germany) and electron micrographs with a Jeol JSM-6400 scanning electron microscope (Tokyo, Japan).

Taxonomy

Diplococcium dimorphosporum M. Hern.-Rest., J. Mena, Gené & Guarro, sp. nov. (Figs. 1a-c, 4a-f)

Fig. 1
figure 1

a-c Diplococcium dimorphosporum, IMI 398788: a, habit; b, Selenosporella synanamorph; c, conidiophores and conidia. Scale bars: a = 100 μm; b, c = 10 μm

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Fig. 2
figure 2

a-c Diplococcium racemosum, IMI 396972: a, habit; b, conidiophores; c, conidia. Scale bars: a = 100 μm; b, c = 10 μm

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Fig. 3
figure 3

a-d Diplococcium singulare, IMI 398787: a, habit; b, conidia; c, conidiophores, conidiogenous cells and conidia; d, Selenosporella syanamorph from culture. Scale bars: a = 100 μm; b-d = 10 μm

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Fig. 4
figure 4

a-f Diplococcium dimorphosporum, IMI 398788: a-b, conidiophore and conidia from the natural substratum; c-f, Selenosporella synanamorph from the natural substratum. g-k Diplococcium racemosum, IMI 396972: g, h, branched conidiophores from the natural substratum; i-k, branched conidial chains and conidia with pores (arrows). Scale bars: a, k = 20 μm; b-f, h = 10 μm; g = 50 μm; i = 25 μm; j = 80 μm

Full size image

Mycobank. MB 518550

Etymology. Latin, dimorphosporum, referring to presence of two types of conidia.

Coloniae in substrato naturali effusae, brunneae. Mycelium partim superficiale et partim in substrato immersum. Conidiophora macronematosa, mononematosa, decumbens, perramosa, fusca, laevia, septata, usque ad 1.75 mm longa, 3–4 μm lata. Cellulae conidiogenae polytreticae, in conidiophoris incorporatae, terminales vel intercalares, cylindricae, brunneae, laeves. Conidia breviter blastocatenulata, sicca, acropleurogena, obovoidea vel cylindrica, concoloria, brunnea ad pallide brunnea, laevia, 0-3-septata, 13–22 × 5–6 μm. Selenosporellae synanamorphe: Conidiophora macronematosa, mononematosa, erecta ex hyphis vegetativis an velut rami e conidiophoris Diplococcii orientia, ad basim atrobrunnea, apicem versus pallidiora, laevia, verticillis induta cellularum conidiogenarum vel verticillis ramorum ad apices aliquot cellulis cum conidiogenis terminatis. Cellulae conidiogenae polyblasticae in conidiophoris incorporatae vel discretae ex verticillis, sympodiales, denticulatae, lageniformes, at basim atrobrunneae, apicem versus pallidiores, 8–24 × 2.5–4 μm. Conidia solitaria, in massis mucosis aggregata, falcata vel filiformia, hyalina, laevia, 0-septata, 8–15 × 0.8–1 μm. Teleomorphosis ignota.

Colonies on the natural substratum effuse, brown. Mycelium partly superficial, partly immersed in the substratum. Conidiophores macronematous, mononematous, prostrate, extensively branched, dark brown, smooth, septate, up to 1.75 mm long, 3–4 μm wide. Conidiogenous cells polytretic, integrated, terminal or intercalary, cylindrical, brown and smooth. Conidia in short chains, dry, acropleurogenous, obovoides or cylindrical, pale brown to middle brown, concolorous, smooth, 0-3-septate, usually slightly constricted at the septa, 13–22 × 5–6 μm; sometimes also produced on Selenosporella conidiophores. Selenosporella synanamorph: Conidiophores macronematous, mononematous, erect from hyphae or as branches from Diplococcium conidiophores, simple or branched, brown at the base, paler at the apex, smooth. Conidiogenous cells polyblastic, integrated or discrete, arranged in whorls, mostly terminal, with narrow sympodial denticulate apices, lageniform, dark brown at the base, lighter towards the apices, 8–24 × 2.5–4 μm. Conidia solitary, often accumulated in slimy heads, falcate or filiform, hyaline, smooth, 0-septate, 8–15 × 0.8–1 μm. Teleomorph unknown.

Holotype. IMI 398788, Spain, Aragón, Ordesa y Monte Perdido National Park, Bielsa valley, 42°38′47″ N, 0°09′2,18″ E, 1195 masl., on dead wood, 18/06/2009, M. Hernández-Restrepo, J. Mena Portales & J. Cano (Isotype: FMR 10787).

Cultures. In spite of the attempts using different techniques, the fungus did not grow in vitro.

Comments. Diplococcium dimorphosporum can be distinguished from other species of the genus because its conidia are not banded, it produces very short conidial chains and its conidiophores are smooth and branched. It is morphologically close to D. clarkii M.B. Ellis, D. pandani B. Huguenin, D. pulneyense Subram. & Sekar and D. stoveri (M.B. Ellis) R.C. Sinclair, Eicker & Bhat, especially in the size of conidia (Goh and Hyde 1998). However, the conidia of D. clarkii are wider (5.6–9 μm) and banded at the septa, in D. pandani they are predominantly non septate, D. pulneyense has long and dendroid conidial chains, and the conidia of D. stoveri are 1-7-septate and wider (14–33 × 6–9 μm), and the conidiophores are unbranched. In D. hugesii, the other species of the genus that produces a Selenosporella-like synanamorph, conidial size of the synanamorph resembles that of the current species, but the Diplococcium state conidia are unicellular and smaller (7–12 × 5–7 μm) (Wang and Sutton 1998). Diplococcium stoveri was described with an in vitro synanamorph, but it has monophialidic conidiogenous cells and the conidia are cylindrical, setulate and 0-4-septate (Shirouzu and Harada 2008).

Diplococcium racemosum Silvera, Mercado, Gené & Guarro sp. nov. (Fig. 2 a-c, Fig. 4g-k)

Mycobank. MB 518556

Etymology. Latin, racemosum, referring to the presence of branched conidiophores and branched chains of conidia.

Coloniae in substrato naturali effusae, brunneae vel atrobrunneae. Mycelium partim superficiale, partim in substrato immersum. Conidiophora macronematosa, mononematosa, erecta, ramosa, brunnea, verrucosa, septata, usque ad 750 μm longa, 3–4.5 μm crassa; rami usque ad 225 μm longi, 3–3.5 μm crassi. Cellulae conidiogenae polytreticae, terminales vel intercalares. Conidia catenulata, sicca, acropleurogena, ellipsoidea vel cylindrica, brunnea, concoloria, crassitunicata, verrucosa, 1-4-septata (plerumque 1-2-septata), ad septa non tenuiora vel leviter tenuiora, septis cum crassis et atrioribus, 11–36 × 5–7 μm. Teleomorphosis ignota.

Colonies on the natural substratum effuse, brown or dark brown. Mycelium partly superficial partly immersed in the substratum. Conidiophores macronematous, mononematous, erect, branched, brown, distinctly verrucose, septate, up to 750 μm long, 3–4.5 μm thick; branches up to 225 μm long, 3–3.5 μm thick. Conidiogenous cells polytretic, terminal or intercalary. Conidia in long and often branched chains, dry, acropleurogenous, ellipsoidal or cylindrical, brown, concolorous, thick-walled, mostly verrucose with conspicuous warts, 1-4-septate (mostly 1-2-septate), not narrower or slightly narrower at the septa, septa thick and dark,11–36 × 5–7 μm. Teleomorph unknown.

Holotype. IMI 396972, Spain, Asturias, Picos de Europa National Park, Covadonga, 43°18′15,71″ N, 5°03′1,99″ W, 311 masl., on dead wood, 15/10/2006, A. Mercado-Sierra & C. Silvera (Isotype: FMR 9294).

Cultures. On PCA at 25°C, colonies attained a diameter of 63 mm at 14 days, composed of olive grey (4/E2) and densely cottony mycelial tuffs at the centre, with paler and scarce aerial mycelium towards the periphery; reverse olive grey (4/E2) at the centre, colourless towards the periphery. Colonies on OA at 25°C slow-growing, attaining 22–23 mm at 14 days, umbonate, lanose and dark olive grey (3/F3) at the centre, with scarce pale grey (3/D1) aerial mycelium towards the periphery, margin white, regular and fimbriate; reverse colourless. Sporulation was observed after two weeks. The conidia were larger (14–48 × 5–7 μm, 1-6-septate) than those from the natural substratum.

Comments. Diplococcium racemosum shows similarities with D. asperum Piroz., D. varieseptatum Goh & Hyde (Goh and Hyde 1998) and D. verruculosum Cruz, Gusmao & Castañeda (Cruz et al. 2007) on the basis of conidial morphology. Additionally, D. asperum and D. verruculosum also produce verrucose conidia. However, D. racemosum mainly differs from the mentioned species in having branched conidiophores and branched conidial chains.

Diplococcium singulare M. Hern.-Rest., J. Mena, Gené & Guarro, sp. nov. (Fig.3a-d, Fig. 5a-g)

Fig. 5
figure 5

a-g Diplococcium singulare, IMI 398787: a-e, conidiophores with cylindrical and spherical (arrows) conidiogenous cells, and conidia from the natural substratum; f, g, Selenosporella synanamorph from culture. h-j Diplococcium. pulneyense, CBS 127864: a branched conidiophore and conidial chains from the natural substratum. Scale bars: a-g, i, j = 10 μm, h = 20 μm

Full size image

Mycobank. MB 518551

Etymology. Latin, singulare, referred to the presence of discrete spherical conidiogenous cells a feature not common in other species of the genus.

Coloniae in substrato naturale effusae, brunneae. Mycelium partim superficiale partim in substrato immersum. Conidiophora macronematosa, mononematosa vel aggregata, erecta, recta, simplicia, cylindrica, brunnea, laevia, septata, usque 460 μm longa, 2.5–4 μm lata. Cellulae conidiogenae polytreticae, terminales vel intercalares, in conidiophoris incorporatae, cylindricae ad clavatae, sed statu discreto sphaericae, 6–7 μm latae. Conidia breviter blastocatenulata, sicca, acropleurogena, cylindrica, subcylindrica vel obovoidea, brunnea, laevia, concoloria, 1-4-septata, praecipue 3-septata, ad septa non tenuiora, 12.5–40 × 5–9 μm. Selenosporellae synanamorphe in vitro: Conidiophora semi-macronematosa, mononematosa, pallide brunnea, laevia. Cellulae conidiogenae polyblasticae, discretae ex verticillis, vel in conidia Diplococcium interdum procedentia, sympodiales, lageniformes, pallide brunneae, laevia, 12.5–32.5 × 2.5–3.75 μm. Conidia solitaria, in massis mucosis aggregata, falcata vel filiformia, hyaline, laevia, 0-septata, 6–13 × 1 μm. Teleomorphosis ignota.

Colonies on the natural substratum effuse, dark brown. Mycelium partly superficial, partly immersed in the substratum. Conidiophores macronematous, mononematous or in small groups, erect, straight, unbranched, cylindrical, brown and smooth, up to 460 μm long, 2.5–4 μm wide. Conidiogenous cells polytretic, integrated or discrete, terminal or intercalary, cylindrical to clavate, when discrete spherical, 6–7 μm wide. Conidia in short chains, dry, acropleurogenous, cylindrical with rounded ends, subcylindrical to obovoid, brown, concolorous, smooth, 1-4-septate, mainly 3-septate, not narrower at the septa, 12.5–40 × 5–9 μm. Teleomorph unknown.

Holotype. IMI 398787, Spain, Aragón, Ordesa y Monte Perdido National Park, Fanlo, Añisclo canyon, 42°35′34″ N, 0°01′34″ W, 1315 masl., on dead wood, 19/06/2009, M. Hernández-Restrepo, J. Mena Portales & J. Cano (Isotype: FMR 10752; Culture ex-type: CBS 126091).

Cultures. Colonies at 25°C after 14 days growing slowly, attaining a diameter of 15–18 mm on PCA and 20–25 mm on OA, cottony, glabrous towards the periphery, dark brown (4E2), margin fimbriate; reverse black. Sporulation was observed after 5 weeks. The conidia were 1-3-septate, 15–25 × 5.5–7.5 μm. At this period the fungus developed a Selenosporella synanamorph not previously observed on the natural substratum. Selenosporella synanamorph: Conidiophores semi-macronematous, mononematous, bearing whorls of conidiogenous cells, pale brown, smooth. Conidiogenous cells polyblastic, discrete arranged in whorls, or growing on Diplococcium conidia, or solitary directly from mycelia, sympodial, with a long and denticulated neck, lageniform, pale brown, smooth, 12.5–32.5 × 2.5–3.75 μm. Conidia solitary, often accumulated in slimy heads, falcate or filiform, hyaline, smooth, 0-septate, 6–13 × 1 μm.

Comment. Diplococcium singulare resembles D. clarkii and D. variseptatum Goh & K.D. Hyde in conidial morphology. However, in D. clarkii they are smaller (16–32 × 5.6–9 μm) and with the septa thicker, while those of D. variseptatum are larger (11–55 × 5–15 μm) and with more septa (up to 5-septate) (Goh and Hyde 1998). Diplococcium singulare is also distinguished by narrow and unbranched conidiophores and especially by the presence of discrete and spherical conidiogenous cells. The Selenosporella synanamorph observed in D. singulare is very similar to the synanamorphs described in D. dimorphosporum and in D. hugesii, but differs only in having conidiophores not well differentiated and conidiogenous cells with a slightly longer neck.

Diplococcium pulneyense Subram. & Sekar, Kavaka 15(1-2): 91 (1987) (Fig. 5h-j)

Colonies on the natural substratum effuse, velvety, brown to dark brown. Mycelium partly superficial, partly immersed in the substratum. Conidiophores macronematous, mononematous, extensively branched, dark brown, smooth, up to 360 μm long, 3 μm wide, 3.5–5 μm at the apex, 5 μm at the base. Conidiogenous cells polytretic, pores inconspicuous after conidial secession, integrated, terminal and intercalary, cylindrical, brown and smooth. Conidia in branched chains, dry, acropleurogenous, cylindrical, pale brown to mid brown, concolorous, smooth, (0-)1-septate, 7.5–8.5 × 4–4.2 μm (0-septate), 9–15.5 (-17) × 4–5 μm (1-septate).

Cultures. On OA and PCA at 25°C colonies growing slowly, attaining a diameter of 15 mm at 14 days, cottony, convex and olive brown (4/E4), margin regular to fimbriate; reverse sepia brown (4/F4). Sporulation was obtained after 2 week. Conidia in long and often branched chains, (0-)1(-2)- septate, 6–9.5 × 4–5 μm (0-septate), 9–32 × 4–6 μm (1-2-septate).

Specimen examined. Spain, Valencia, Chera, Chera-Sot Natural Park, Pantano de Buseo, 39°35′40″ N, 0°56′22″ W, 481 masl., on dead wood, 15/03/2010, M. Hernández-Restrepo & K. Rodríguez (FMR 10959, CBS 127864).

Comment. This species only had been isolated from dead wood in Tamil Nadu, India, and considered the anamorphic state of Otthia pulneyensis Subram. & Sekar. The original description of D. pulneyense is based only on its development in pure culture. The Spanish specimen on the natural substratum produces smaller and 0-1-septate conidia, but the morphology of the conidia on both OA and PCA fits with that of the protologue (Subramanian and Sekar 1987). A feature not mentioned in the original description of the species is the presence, both in culture and on natural substratum, of aseptate conidia occurring in an intercalary position in the conidial chains.

Key to accepted species of Diplococcium

  1. 1.

    Conidia verrucose or verruculose............................................................2

  2. 1*.

    Conidia smooth........................................................................................4

  3. 2.

    Conidiophores branched...................................................D. racemosum

  4. 2*.

    Conidiophores unbranched.......................................................................3

  5. 3.

    Conidia oblong to cylindrical, 1-4-septate, 9–25 × 4.5–6 μm......................D. verruculosum

  6. 3*.

    Conidia ellipsoidal to obcIavate, 1-septate, 15–20 × 6–7 μm.....................D. asperum

  7. 4.

    Conidia often produced on terminal or lateral spherical conidiogenous cells, 1-4-septate (mostly 3-septate)......................................D. singulare

  8. 4*.

    Spherical conidiogenous cells absent........................................................5

  9. 5.

    Conidia versicolored, with one or more cells distinctly darker than the other..................................6

  10. 5*.

    Conidia concolorous, with all the cells of the same color........................14

  11. 6.

    Conidiophores branched...........................................................................7

  12. 6*.

    Conidiophores unbranched.................................................................... 10

  13. 7.

    Conidia 0-septate, ovate to obpyriform, 8.5–13 × 5.5–8 μm................D. parcum

  14. 7*.

    Conidia 1-septate, ellipsoidal, clavate, obclavate or lageniform, 4–6 μm wide...........8

  15. 8.

    Conidiophores dichotomously branched; conidia ellipsoidal, obovoid or clavate, 9–16.5 × 4.5–6 μm.........D. lawrencei

  16. 8*.

    Conidiophores irregularly branched; conidia pyriform, obclavate or lageniform........................9

  17. 9.

    Conidia obclavate to lageniform, septum closer to the apex, not constricted at the septum, basal cell darker than apical cell, 11–20 × 4.5–5 μm..................D. bicolor

  18. 9*.

    Conidia pyriform to ellipsoidal, septum closer to the base, constricted at the septum, apical cell darker than the basal cell, 5–13 × 4–5 μm......................D. aquaticum

  19. 10.

    Conidia 1-septate, 11–15 × 3–4.5 μm; on dead grass culms.....................D. graminearum

  20. 10*.

    Conidia 2- or 3-septate, 9.5–40 μm long, 7–13 μm wide; on dead leaves or rotten wood........................11

  21. 11.

    Conidia 2-septate, constricted at septa, subellipsoidal, central cell larger and darker than end cells, 17–25 × 7–9 μm, borne in acropetal chains; occurring on dead leaves....................D. laxusporum

  22. 11*.

    Conidia 2- or 3-septate, of other shapes or combination of conidial characters not as above; occurring on rotten wood.................12

  23. 12.

    Conidia 2-septate, usually with the base broader than the apex, 9.5–22 × 8–11 μm................D. insolitum

  24. 12*.

    Conidia mostly 3-septate, apex broader than the base................13

  25. 13.

    Conidia 20–40 × 8–10 μm, constricted at the septa.............D. constrictum

  26. 13*.

    Conidia 16–26 × 8–13 μm, not constricted or rarely slightly constricted at the septa.................D. grovei

  27. 14.

    Conidiophores branched................................................15

  28. 14*.

    Conidiophores unbranched............................................23

  29. 15.

    Conidia clavate, obclavate, ellipsoidal or subcylindrical, 5.5–15 μm wide; occurring on fruit bodies of basidiomycetes..........16

  30. 15*.

    Conidia subglobose, oblong, obovoid or cylindrical, 3–7.5 μm wide; occurring on wood or leaves.........................18

  31. 16.

    Conidia 0-1-septate, 13–29 × 6–9 μm; overgrowing carpophores of Clavariaceae................D. clavariarum

  32. 16*.

    Conidia with 2-3 or more septa; overgrowing carpophores of Corticiaceae........................17

  33. 17.

    Conidia (11-)19–42(-55) × (5-)7–11(-15) μm, with 1-5 septa, cylindrical to ellipsoidal........................D. varieseptatum

  34. 17*.

    Conidia 16–32 × 5.5–9 μm, mostly 3-septate, ellipsoidal, obclavate or subcylindrical........................D. clarkii

  35. 18.

    Selenosporella synanamorph present................................19

  36. 18*.

    Selenosporella synanamorph not observed...............................20

  37. 19.

    Conidia subglobose, oval to oblong, 0-septate, 7–12 × 5–7 μm.......................D. hughesii

  38. 19*.

    Conidia obovoid or cylindrical, 0-3-septate, 13–22 × 5–6 μm...................D. dimorphosporum

  39. 20.

    Conidia mostly 1-septate; occurring on rotten wood.................21

  40. 20*.

    Conidia mostly 0-septate.............................................22

  41. 21.

    Conidia 6–9 × 3–4 μm..............................................D. spicatum

  42. 21*.

    Conidia 7.5–17 × 4–5 (in vitro 6–32 × 4–6 μm)...................D. pulneyense

  43. 22.

    Conidia 8–40 × 4.5–6 μm, occasionally 1-3-septate; occurring on living leaves of Pandanus................................D. pandani

  44. 22*.

    Conidia 8–23 × 4–7 μm, occasionally 1-septate; on spikelets of Scleria levis...........................D. atrovelutinum

  45. 23.

    Occurring on stromata of Diatrype; conidiophores 3–3.5 μm wide; conidia 0-1-septate, 4.5–10 × 2.5–4 μm...................D. heterosporum

  46. 23*.

    Occurring on bamboo culms or palm material; conidiophores wider; conidia larger........................24

  47. 24.

    Conidia 0-septate, 7.5–12 × 2.5–5.5 μm; conidiophores 3.5–4 μm wide, with conidiogenous pores confined to swollen terminal cell..................D. capitatum

  48. 24*.

    Conidia 1-7-septate, 12–34 × 6–10.5 μm; conidiogenous pores not as above....................25

  49. 25.

    Conidia (1-2-)3-7-septate, constricted, not darkly pigmented at the septa, cylindro-obclavate, 14–33 × 6–9 μm................D. stoveri

  50. 25*.

    Conidia 1(-2)-septate, not constricted, darkly pigmented at the septa, oblong, ellipsoidal, broadly fusiform or ovate.............................26

  51. 26.

    Conidia oblong or ellipsoidal, 12–22 × 6–9 μm; conidiophores 7.5–12 μm wide; occurring on decaying bamboo culms...................D. dendrocalami

  52. 26*.

    Conidia broadly fusiform or ovate, 12–34 × 7–10.5 μm; conidiophores 4–6 μm wide; occurring on rotten palm petioles....................D. peruamazonicum