Mycologia ISSN: 0027-5514 (Print) 1557-2536 (Online) Journal homepage: https://www.tandfonline.com/loi/umyc20 A new species of Rhexoampullifera from leaf litter from Brazil Rafael F. Castañeda-Ruíz, Josepa Gené & Josep Guarro To cite this article: Rafael F. Castañeda-Ruíz, Josepa Gené & Josep Guarro (2001) A new species of Rhexoampullifera from leaf litter from Brazil, Mycologia, 93:1, 168-170, DOI: 10.1080/00275514.2001.12061287 To link to this article: https://doi.org/10.1080/00275514.2001.12061287 Published online: 04 Jun 2019. Submit your article to this journal View related articles Citing articles: 1 View citing articles Full Terms & Conditions of access and use can be found at https://www.tandfonline.com/action/journalInformation?journalCode=umyc20 Mycologia, 93(1), 2001, pp. 168-170. © 2001 by The Mycological Society of America, Lawrence, KS 66044-8897 A new species of Rhexoampullifera from leaf litter from Brazil Rafael F. Castafieda-Rufz natural substratum revealed that its conidial ontogeny and secession strongly resemble to those of R Jagi (M.B. Ellis) P.M. Kirk (1982), although the two taxa clearly present quite different morphological characteristics. Rhexoampullifera Jagi has micronematous conidiophores supported by brown hyphae with stipitate, cylindrical, globose or hemispherical to clavate, sometimes curved, pale brown to brown hyphopodia, while in the new species the conidiophores are macronematous and hyphopodia are not present. In addition, R Jagi has 1-4-septate, cylindrical to doliiform, 24-26 X 7-10 JLm, dark brown conidia, and those of the new species are subglobose, turbinate or cylindrical to navicular, 12-24 X 10-13 JLm, 0-2-sep- /nstituto de Investigaciones Fundarrumtales en Agricultura Tropical "Alejandro de Humboldt" (IN/FAT) calle 1, esq. 2, Santiago de Las ltegas, Ciudad de La Habana, Cuba, C.P.17200 Josepa Gene 1 Josep Guarro Unitat de Microbiologia, Facultat de Medicina i Ciencies de la Salut, and Institut d'Estudis Avant:ats, Universitat Riroira i Virgili, 43201-Reus, Tarragona, spain Abstract: Rhexoampullifera subglobosa anam. sp. nov., characterized by subglobose, turbinate, navicular to irregular, septate, two-colored (dark brown to black and pale brown) conidia emerging from conspicuous, repeatedly branched conidiophores, is described and illustrated. It was collected on decaying leaves of an unidentified member of the Myrtaceae in Brazil. Key Worth: hyphomycetes, plant debris During studies of microfungi collected on different substrata and habitats in Brazil, an interesting dematiaceous hyphomycete was found on decaying leaves of an unidentified member of the Myrtaceae. The fungus ultimately proved to belong to the genus Rhexoampullifera P.M. Kirk. The genus Rhexoampullifera (Kirk 1982) is distinguished by micronematous conidiophores and determinate, monoblastic or polyblastic conidiogenous cells. The acropetally elongating chains of conidia, its basipetally maturation and the rhexolytic secession of the conidia were used as criteria to separate Ampulliferinafagi M.B. Ellis (1976) from the genus Ampulliferina B. Sutton (1969) to erect the new genus Rhexoampullifera. The combination of such characteristics, considered as unique in the dematiaceous hyphomycetes with holoblastic catenate conidia, justified this proposal (Kirk 1982). Despite repeated efforts, we were not able to obtain growth of the new species in axenic cultures. A careful examination of the fungus growing on the '' 'Itt• FIG. 1. Rhexoampullifera subglobosa, MUCL 40709. Conidiophores and conidia. Bar = 25 IJ.ID. Accepted for publication July 3, 2000. 1 Corresponding author, e-mail: umb@fmcs.urv.es 168 Published online 04 Jun 2019 CAsTANEDA-RUiZ ET AL: R. SUBGLOBOSA SP. NOV. 169 FIGS. 2-9. Rhexoampullifera subglobosa, MUCL 40709. 2. Branched conodiophore. 3-7. Conidial chains. 8, 9. Conidia showing rests of the conidiogenous cell after the rhexolytic secession. Bars: 2 = 20 JJ.m; 3-9 = 10 JJ.m. tate, with one cell dark brown to black and the rest subhyaline to pale brown. In both species the fragmentation of the conidial chains occurs in the paler pigmented separating cell between conidia, and the liberated conidia always show evidence of this at one or two poles. Furthermore, in the new species the conidia, when mature, remain attached to the conidiogenous cells forming chains. Another peculiarity of this species is that intercalary cells of the conidiophore stalk become pigmented and thick-walled, suggesting the possibility that more conidia might develop from them, although this could not be proven. Rhexoampullifera subglobosa R. F. Castaneda, Gene et Guarro, anam. sp. nov. FIGS. 1-9 Coloniae in substrato naturali effusae, amphigenae, granulo-racemosae, nigrae. Mycelium partim superficiale et partim in substratum immersum, ex hyphis septatis, laevibus, ramosis, brunneis, 1.5-3 JJ.m diam., compositum. Conidiophora conspicua, mononematosa, fasciculata, septata, erecta, levia, itero ramosa, inflata usque subglobosa ad basim, 120-270 X 8-10 JJ.m, primo brunnea tarde brunnea infra, atrobrunnea supra, interdum alterno pigmentata in parte intermediis cum nonnullis celluli brunneis et alter atrobrunneis alterno disposita. Cellulae conidiogenae holoblasticae, terminales, intercalares, determinatae, discretae. Con- 170 MYCOLOGIA idiorum secessio rhexolytica. Conidia in catenis, simplicibus vel ramosis, acrogena, sicca, levia, 0-2-septata, subglobosa usque ad turbinata, 12-24 X 10-13 JLm, inaequiseptata et bicoloria, cum cellula centralis magna, 10-20 X 10-13 JLm, atrobrunnea vel nigra, cellula apicali minor, 3-5 X 6.5-9 JLm, subhyalina, et cellula basali irregularia, subhyalina, 412 X 5-6 JLm; conidia interdum cylindrica usque ad navicularia, atrobrunnea, 19-21 X 9-14 JLm, reliquia 2-15 X 55.5 JLm, ad basim vel utrimque conidia plerumque adhesa. Plerumque omnia conidia in maturitate persistentia catenata et in loco conidiogeno. Teleomorphosis ignota. Colonies on the natural substratum effuse, amphigenous, granulose, black. Mycelium superficial and immersed. Hyphae septate, smooth-walled, branched, brown, 1.5-3 J.Lm diam. Conidiophores macronematous, mononematous, fasciculate, septate, erect, smooth-walled, repeatedly branched, inflated to subglobose acthe base, 120-270 X 8-10 J.Lm, at first brown, later brown below and dark brown above, sometimes in the intermediate part light brown cells are alternately arranged with dark brown cells. Conidiogenous cells holoblastic, terminal and intercalary, determinate. Conidial secession rhexolytic. Conidia formed in simple or branched acropetal chains, dry, smooth-walled, subglobose to turbinate, 12-24 X 1013 J.Lm, 0-2-septate, asymmetrical, two-colored, with a central cell dark brown to black, 10-20 X 10-13 J.Lm, larger than the other cells, an apical cell subhyaline, 3-5 X 6.5-9 J.Lm, and a basal cell irregular, pale brown, 4-12 X 5-6 J.Lm; conidia sometimes cy- lindrical to navicular, dark brown, 19-21 X 9-14 J.Lm; always with remnants of the conidiogenous cell attached at the base or ends of the conidia, 2-15 X 55.5 J.Lm. Frequently all conidia remaining attached to the conidiogenous cells at maturity. Teleomorph unknown. specimen examined. BRAZIL. Mata Avenca-Santa Rita, on fallen decaying leaves of an unidentified member of the Myrtaceae, 10 Sep 1997, J Guarro (HOLOTYPE: MUCL 40709; ISOTYPE: IMI 380272). Etymology. From the Latin subglobosa, referred to conidial shape. Known distribution. Brazil. Habitat. Saprobic on plant debris. Acknowledgments.-We are deeply indebted to Dr. M. Vmcent (Miami University) for his helpful comments on the fungus described above. We thank the Cuban Ministry of Agriculture for facilities. This work was supported in part by the Fundaci6 Ciencia i Salut, Reus (Spain), and CITMA (Cuba) through the project 20-11. UTERATURE CITED Ellis MB. 1976. More dematiaceous hyphomycetes. Kew: Commonwealth Mycological Institute. 507 p. Kirk PM. 1982. New or interesting microfungi. V. Microfungi colonizing Laurus nobilis leaf litter. Trans Br Mycol Soc 78:293-303. Sutton BC. 1969. Forest microfungi. I. Ampulliferina persimplex n. gen., n. sp. on leaves of labrador tea. Can J Bot 47:609-616.