[269 ] PERISPORIALES BY M. J. THIRUMALACHAR. (With Plate 6 and 7 figures in the te.xt)

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1 [269 ] ASTOMELLA, A NEW MEMBER OF THE PERISPORIALES BY M. J. THIRUMALACHAR (With Plate 6 and 7 figures in the te.xt) An ascomycetous fungus collected on the leaves of Neolitsea zeylanica in Nandi Hills, Mysore, proved on examination to be of unusual interest, having characters quite different from those of any other fungus so far described. The fungus is hypophyllous and superficial, the closely interwoven cinnamon-yellow hyphae (PL 6, fig. i) forming a dense woolly mass of covering on the surface of the leaves. In early stages of infection, the fungus forms small cinnamon-brown patches on the lower surface of the leaves, and as development proceeds these coalesce with one another. In later stages the perithecia are seen embedded within the hyphal mass, appearing as tiny reddish black specks. After the completion of the production of the perithecia the felt of mycelium begins to peel off as thin crusts. Sections through the leaves indicate that the fungus forms a basal substratum of creeping hyphae, from which erect circinate branches are formed in large numbers, thus producing a heterotrichous habit. The epidermal cells of the host are penetrated by haustorial processes formed by the hyphal strands. The felt of mycelium is so delicately attached to the host that it is very difficult to demonstrate the penetration of the fungus within the host, especially in later stages, when the entire felt of mycelium begins to peel away from the host. In very early stages, when the mycelium is arachnoid creeping on the leaf surface, the penetration into the epidermal cells and the consequent depletion of their cell contents have been observed. In fact, the presence of the fungal patches on the lower surface of the leaves is clearly indicated by the discoloration of the host in corresponding places on the upper surface. This confirms the parasitic nature of the fungus, which in its mode of parasitism resembles to a very great extent the ectoparasitic alga, Cephaleuros mycoidea Karst. The mycelium is septate, cinnamon-yellow, creeping on the surface of the leaves and sending in haustorial processes into the epidermis. There are no hyphopodia so characteristic of many of the Perisporiaceae, but circinate erect branches which could be compared morphologically with setae are present in large numbers. The hyphae are not uniformly broad, but develop here and there numerous nodular or hemispherical bulges (Text-fig. 2). The perithecia are found embedded within the hyphal felt, appearing macroscopically as tiny globular bodies. They can be collected in abundance in the months between November and February, after which they are either absent or completely empty. Mature perithecia are reddish brown, subglobose to spherical, /x in diameter and smooth. They do not possess any appendages, nor have they any ostiole or any similar structure for the escape of the ascospores. The perithecia are therefore astomous and cleistocarpous. The wall of the perithecium is composed of two distinct layers. The outer one is reddish brown, one-layered, hard and circumcissile. It appears to be composed of septate meandering hyphae (Text-fig. 4). The inner wall is also one-layered

2 270 M. J. THIRUM.\LACHAR though in optical sectional view it appears to be two- to three-layered (Text-fig. 4), and is composed of polygonal cells. This inner hyaline layer is comparable both in structure and development with the peridial layer described by Gaumann (1922) in Lanomyces tjibodensis Gaiim. from Java. Ttxt-hg. I. Showinj^ the niycelium with perithecia. x 200. Text-iie. 2. Septate h>'phae with heniispherical bulges. ^ Text-fig. 3. Sho\\ing the unibcuate cluster of asci. x 400. Text-tig. 4. Dchiscence of the peritheciuni. x 400. Text-rtg. 5. Aseus show ing the biseriate arrangement of the spores. X 800. Text-fig. 6. Portion of the inner hyaline wall layer showing the parenchyniatous cells. X 800. Text-fig. 7. Mature ascospore showing i-septate condition, x The asci are from four to ten in number, developed in a basal umbellate cluster. Consequently in the development and disposition of the asci it diiters considerably from the members of the Eurotiaceae where the asci are scattered irregularly and very rarely

Astomella, a new member of the Perisporiales 271 grouped in corymboid clusters. Mature asci are clavate to obovate, hyaline, and are attached at the base.

3 Astomella, a new member of the Perisporiales 271 grouped in corymboid clusters. Mature asci are clavate to obovate, hyaline, and are attached at the base. The ascospores are eight in number, pale cinnamon-yellow in colour and uniseptate. They are rounded at both ends, slightly constricted at the septa, smooth (Text-fig. 7) and measuring x ii-14/x. The spores within the ascus are arranged biseriately. Considerable difficulty was experienced in securing mature perithecia with fully developed ascospores, as most of the perithecia were found to be either empty or containing only immature asci. Consequently, large collections of the material with perithecia in all stages of development were examined carefully from time to time. It became evident that as the perithecia approached maturity the asci and ascospores along with the inner wall layer were forcibly ejected after a bivalvular cracking of the perithecium. Some ripe perithecia that were examined under the low power of the microscope suddenly ejected the asci with the ascospores, all of which were still enclosed within the inner wall when just teased with a needle (Text-Bg. 4). The ascospores at this stage are still in the process of development, the septation within them not having taken place. It therefore seems probable that the dispersal of the asci with the ascospores takes place just before the complete ripening of the latter. This probably explains the scarcity of the mature ascospores. The superficial mycelia forming a woolly felt-like covering on the surface of the leaves with perithecia embedded within them, recalls the condition present in the genera Cryptothecium Penz. & Sacc. and Lanomyces Gaum. In Cryptothecium javanicum Penz. & Sacc. (Penzig & Saccardo, 1897), described from Java on Ekttaria, the perithecia were found on decaying leaves and were stated to be astomous and possessing amerospores which were 6- to 8-guttulate. The fungus was collected again in the same locality by von Hohnel in Java on the same substratum, which, however, was identified as Amomum and not Ekttaria. The perithecia, according to v. Hohnel (1909), are not, however, astomous, but possess a small ostiole with distinct radiating periphyses. v. Hohnel concluded, therefore, that it was a member of the Nectriaceae. The plasma of the ascospores showed slender divisions into four or sometimes six parts, and he regarded the species as belonging to the genus Calonectria. Since no definite septations were noticed in the ascospores and to meet correct descriptions of the i-celled state, he also named the fungus as Byssonectria javanica (Benz. & Sacc.) Hohnel. Since Cryptothecium is now regarded as a synonym of Byssonectria or Calonectria (according to Clements & Shear (1931)), the present fungus on Neolitsea zeylanica cannot be identified with that genus. Lanomyces tjibodensis, described by Gaiimann (1922) in Java, possesses similar felt-like mycelium with erect, circinate branches. The mycelium, however, is intramatrical to start with, emerging and becoming superficial later. The perithecia are borne on the superficial mycelium which is simple and exhyphopodiate. They are astomous, but each possesses a single ascus containing numerous (more than eight) i-celled ascospores. In the present fungus, however, there are 6-10 asci with 2-celled ascospores. As the fungus under study differs in essential features from all other genera of fungi so far known, the writer proposes to accommodate it in a new genus under the Perisporiales. The name Astomella is proposed. Astomella Thirumalachar gen. nov. Mycelium superficial, processibus haustoriis in epidermate praeditum, lanosum, cinnamomeo-brunneum. Perithecia superficialia, in hypharum massa insidentia, globosa, luteo-brunnea, astomata; integumentum duplex, pariete exteriore rubro-brunneo ex

4 272 M. J. THIRUMALACHAR hyphis vagantibus composito, interiore vero hyalino, parenchymatico. Asci 6-10, aparaphysati, 8-spori; sporae uniseptatae; asci cum pariete interiore in maturitate vehementer e.xpelluntur. Species typica Astomella Neolitseae Thirumalachar. Mycehum superficial with haustorial processes within the epidermis, woolly, cinnamonbrown. Perithecia superficial, buried in the hyphal mass, globose, yellowish brown, astomous, with two distinct wall layers; outer reddish brown, formed by septate meandering hyphae, inner hyaline, i-layered and parenchymatous. Asci 6-10, aparaphysate, S-spored; spores i-septate; asci along with inner wall forcibly ejected at maturity. Type species Astomella Neolitseae Thirumalachar. Astomella Neolitseae Thirumalachar sp.nov. Fungus hypophyllus, pallide luteus, maculas in facie superiore foliorum efficiens; mycelium superficial, initio arachnoideum, postea cinnamomeo-brunneum atque lanuginosum, haustoriis in epidermate evolutis, ramis circinatis setae simihbus. Perithecia superficialia, globosa ad subglobosa, luteo-brunnea, astomata atque cleistocarpa, ju, diam.; perithecii integumentum duplex, pariete exteriore rubro-brunneo, ex hyphis septatis vagantibus composito, duro, in maturitate fissione bivalvata dehiscente; pariete interiore hyalino, parenchymatico, cellulis rectangularibus vel polygonalibus. Asci 6-10, clavati vel obovales, in acervo umbellato dispositi, aparaphysati, 8-spori, magnitudinis x35-45/11. Sporae ovatae, uniseriatae, biseriatim dispositae, cinnamomeo-luteae, utrinque rotundatae, ad septa paullo constrictae, laeves, magnitudinis 22-30x11-14/*. Asci atque sporae simul cum pariete interiore in maturitate vehementer expelluntur. Habitat in foliis Neolitseae sevlanicae, Nandi Hills, Mysore, 14. x. 1944, leg. M. J. Thirumalachar. Typus positus in Herb. Crypt. Ind. Orient., New Delhi, et in Herb. I.M.I., Kew, Anglia. Hypophyllous, causing pale yellowish patches on the upper surface, mycelium superficial, arachnoid in the beginning and cinnamon-brown and woolly later on, developing haustoria within the epidermis, with circinate setae-like branches. Perithecia superficial globose to subglobose, yellowish brown, astomate and cleistocarpous, /^ in diameter with two-layered wall; outer reddish brown, formed by the septate meandering hyphae, hard, opening at maturity by bivalvular split; inner hyaline, one-layered and parenchymatous, cells rectangular to polygonal. Asci 6-10, clavate to obovate, arranged in umbellate cluster, aparaphysate measuring x 35-45/u, 8-spored. Spores ovate, I-septate, biseriately arranged, cinnamon-yellow, rounded at both ends, slightly constricted at the septa, smooth and measuring x n-14/n. Asci and spores along with the inner wall layer ejected forcibly at maturity. Habitat on the leaves of Neolitsea zevlaiiica, Nandi Hills, Mysore, 14. x. 1944, leg. M. J. Thirumalachar. Type deposited in the Herb. Crypt. Ind. Orient., New Delhi, and in Herb. I.M.I., Kew, England. In the possession of superficial mycelia bearing globose astomous perithecia, the genus Astomella has characters in common with the members of Eurotiaceae, Krysiphaceae, and

$THE NEW PHYTOLOGIST, 46, 2 PLATE 6 Fig. I. Photograph of the icni oi Xcohtsfd zeylanica..>. '\ nat. sv/.v. Fig. 2. Photomicrograph showing the dehisccnce of the ptnthcciuni.$

5 THE NEW PHYTOLOGIST, 46, 2 PLATE 6 Fig. I. Photograph of the icni oi Xcohtsfd zeylanica..>. '\ nat. sv/.v. Fig. 2. Photomicrograph showing the dehisccnce of the ptnthcciuni. x about 400. THIRUMALACHAR. i5ro.v 'LL.-J, A NEW MEMBER OV THE PERISPORIALES

6 Astomella, a new member of the Perisporiales 273 Perisporiaceae of Clements & Shear (1931), who group all the three families under Perisporiales. In Eurotiaceae most of the members are saprophytic, the asci being formed irregularly or in corymboid clusters. In both Erysiphaceae and Perisporiaceae, on the other hand, the asci are basal in umbellate clusters, a character found in the present genus also. The genus Astomella might therefore be placed either under Erysiphaceae or Perisporiaceae. In this connexion it might be pointed out that Lanomyces Gaumm., which has coloured mycelium unlike most of the other genera of Erysiphaceae, is placed by Gaumann between Erysiphaceae and Perisporiaceae and under Erysiphaceae by Clements & Shear. The genus Astomella might also be placed along with Lanomvces as an aberrant genus under Erysiphaceae, having perithecia with many asci and once septate spores. The coloured mycelium and the bright reddish brown perithecia recall the characters of the Nectriaceae. However, the type of dehiscence of the perithecia is quite unique and differs from the methods of dehiscence so far known in the related groups. In conclusion, the writer wishes to acknowledge his deep sense of gratitude to Mr C. G. Hansford, Kampala, Uganda, for carrying out most of the preliminary work on the fungus and for pointing out to the writer the systematic position of the genus. Grateful thanks are due to Dr S. P. Wiltshire and Mr E. W. Mason of the Imperial Mycological Institute, Kew, England, for going through the manuscript and for giving literature about Cryptothecium. Rev. Dr H. Santapau, Professor of Botany, St Xavier's College, Bombay, very kindly prepared the Latin diagnosis of the genus and species. REFERENCES CLEMENTS, F. E. & SHEAR, C. L. (1931)- The Genera of Fungi. Pp New York: H. VV. Wilson Co. GAUMANN, E. (1922). Ober die Entwicklungsgeschichte von Lanomyces. Ann. Jard. hot. Buitenz. 32, HoHNEL, F. VON (1909). Fragmente zur Mykologie, VIII. No S.B..Akad. IViss. U'ien (Math. nat. Kl.). Abt i, pp PENZIG, O. & SACCARDO, P. A. (1897). Malphigia, (original not seen).

Fungi from palms. XXXIX. Asymmetricospora sp. nov. (Melanommataceae)

Fungi from palms. XXXIX. Asymmetricospora sp. nov. (Melanommataceae) gen. et Jane Fröhlich 1 & Kevin D. Hyde 2 1 Manaaki Whenua, Landcare Research New Zealand Ltd, Private Bag 92170, Auckland, New Zealand