Sclerodermaceae of New Zealand.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 62, 1931-32, Page 115

Sclerodermaceae of New Zealand. By G. H. Cunningham, Mycologist, Plant Research Station, Palmerston North. [Received by Editor, 19th November, 1930; issued separately, 30th September, 1931.] The Sclerodermaceae is a small family of fungi placed by taxonomists under the sub-class Gasteromycetes. The family is limited to the genera Scleroderma and Pisolithus, and is characterised by the method of development, simple peridium and absence of a definite capillitium. In Scleroderma the mature plant consists of a simple, one-layered, tough and (usually) leathery peridium composed of intricately interwoven hyphae and projected basally into a short rooting base from which arise abundant rhizoids which attach the plant firmly to the substratum. The peridium encloses the gleba, which at maturity is pulverulent and composed of spores mixed with scattered hyphal fragments. Dehiscence is effected by the peridium rupturing irregularly into lobes at the apex, exposing the powdery spore mass, which is ultimately dispersed by wind. In some species, as the plant ages the lobes become revolute, giving to old specimens a stellate appearance; and in one, dehiscence is effected by an irregular apical mouth. During the course of development, numerous tramal plates are formed, which are so arranged that the gleba presents a distinctly cellular appearance. As the plant develops these become absorbed gradually, until at maturity little remains but scattered fragments, save in individual plants of one or two species, where the plates partially persist and give to the gleba a veined appearance. In Pisolithus the peridium is similarly organised, but the tissues become infiltrated and so altered as to become carbonous and brittle at maturity. The tramal plates therefore persist and form the feature separating the genus from Scleroderma. And dehiscence is effected by irregular breaking away of the peridium from the apex downwards, which exposes the persistent cells of the gleba and the enclosed spore masses which fill each cell. Scleroderma Persoon ex Fries, Syst. Myc., vol. 3, p. 44, 1829. Scleroderma Pers., Syn. Meth. Fung., p. 150, 1801, pro parte. Solerangium Lev., Ann. Sci. Nat., ser. 3, vol. 9, p. 132, 1843. Stella Mass., Jour. Myc., vol. 5, p. 185, 1890. Plant consisting of a firm, simple peridium which encloses the gleba, and is projected basally into a short rooting base from which arise numerous rooting rhizoids. Peridium of a single tough and pliable membrane, dehiscing by apical rupture into several lobes, which in old specimens often become revolute, or less frequently by an irregular apical stoma. Gleba pulverulent, of spores mixed with a few hyphal fragments. Spores globose, coloured, continuous. Basidia bearing from 1 to 5 spores, which are sessile or produced on short sterigmata.

Type Species: Scleroderma aurantium Pers. Distribution: World-wide. The number of species recorded is large, upwards of 60 being listed in the numerous volumes of Saccardo's Sylloge Fungorum; but as few earlier workers appeared to have had any clear idea as to the specific characters of the genus, it is improbable that there are more than about 10 valid species, the many others being synonyms of these or of species of Mycenastrum or Pisolithus. In New Zealand the genus is apparently represented by two species only, judging from the numerous collections I have examined. The genus has proved a difficult one for the systematist, as most species have been based on characters now known to be too variable for specific delimitation. After an examination of some 95 collections from Australia and New Zealand I have come to the conclusion that the method of dehiscence, colour of the peridium and gleba, and nature of the surface of the peridium (characters commonly used in specific diagnosis) are alone specifically valueless, though, when considered in conjunction with other features, are useful aids in diagnosis; whereas the size and markings of the spores are much more reliable features. But the spores cannot be examined readily unless mounted in a suitable medium. I find a useful mountant to be a 50 per cent. solution of lactic acid in water, to which has been added 0.1 per cent. aqueous solution of analine blue; for if spores are mounted in this and heated to boiling point, their markings are rendered free from obscuring matter and may then be examined critically. Most of the European species were erected by Persoon or Fries; but as they were based on variable characters, and spores were not considered, an interpretation of these species in the light of spore characters is possible only by reference to the work of Hollos (1904), where the spores were first accurately described. Consequently modern workers rely upon Hollos's interpretation of species erected by these earlier workers. The two species present in New Zealand may be separated readily upon the following spore characters:— Spores strongly reticulated 1. S. Bovista. Spores covered with spines 2. S. flavidum. 1. Scleroderma Bovista Fries, Syst. Myc., vol. 3, p. 48, 1829; emend. Hollos, Gast. Ungarns, p. 132, 1904. Figs. 1, 5. S. texense Berk., in Hook. Jour. Bot., vol. 4, p. 308. 1845. Plants solitary or gregarious, to 4 cm. diameter, compressed globose, firm, somewhat plicate below, with a short rooting base and attached firmly to the substratum by numerous rhizoids. Peridium when dry tough, firm, to 0.5 mm. thick, dehiscing by irregular rupture of the apex, externally furfuraceous, or less frequently finely areolate apically, sulphur-yellow or more often bay brown or pallid umber, often somewhat vinaceous. Gleba at first violaceous, becoming umber;

tramal plates often partially persistent, yellow, hyphae with distinct clamp connections. Spores strongly reticulated, globose, 11–16 mmm., deep umber tinted with chocolate, reticulations to 3 mmm. tall. Habitat: Growing amongst grass on sandy or cultivated soil. Type Locality: Germany. Distribution: Europe; North America; New Zealand. Auckland: Buried Village, Wairoa, 2/27, J. B. Cleland, G.H.C.; Whakarewarewa State Forest Nursery, 5/28, G.H.C. Taranaki: Botanical Gardens, New Plymouth, 2/27, G.H.C. Wellington: Wanganui, 4/25, D. W. McKenzie; Palmerston North, 5/30, G.H.C.; Weraroa, 3/25, J. C. Neill. The characters of the species are the strongly reticulated spores, thin but firm, externally smooth peridium, and frequent persistence of portions of the tramal plates, the hyphaeof which possess abundant clamp connections. In the thermal regions specimens are more lax and yellow than those from other localities, but are otherwise identical. The species is often found growing associated with healthy roots of Pinus radiata in the State Forest Nursery at Rotorua, and has been found similarly with strawberry plants at Palmerston North. It is probable therefore that it forms a mycorrhiza with the former (and possibly too, the latter) host, since Peyronel (1922) found “S. vulgare” formed mycorrhiza with roots of Larix decidua and Quercus robur in Italy. 2. Scleroderma flavidum Ellis and Everhart, Jour. Myc., vol. 1, p. 88, 1875. Figs. 2, 6, 7. S. caespitosum Lloyd, Myc. Notes, p. 1159, 1922. Plants solitary or gregarious, sometimes caespitose, growing half buried until maturity, to 5 cm. diameter, firm, pyriform or subturbinate, often lobed, usually plicate below, contracting into a short rooting base, which is attached to the substratum by numerous rhizoids, or sometimes compacted into a conspicuous, stem-like structure. Peridium when dry tough, leathery and seldom brittle, to 1 mm. thick, dehiscing by irregular rupture into several lobes, which in weathered plants frequently become recurved and stellate; pallid or bright yellow, or as often dingy brown, sometimes vinaceous, finally areolate above, sometimes almost smooth. Gleba at first violaceous, becoming ferruginous or umber brown; tramal plates sometimes partially persistent, when yellow. Spores globose, 10–14 mmm., coarsely and densely echinulate; spines acuminately pointed, somewhat narrow at their bases, to 1.5 mmm. long. Habitat: Growing on sandy soil, or partially buried in clay or rock cuttings. Type Locality: New Jersey, North America. Distribution: North America; Africa; Australia; New Zealand. Wellington, 5/22, J. B. Cleland. forma macrosporum. Spores large, commonly 14–16 mmm., sometimes attaining a diameter of 19 mmm., and more coarsely echinulate, spines often appearing in the form of soldered warts. Otherwise identical with the typical form.

Distribution: Australia; New Zealand. Auckland: Waitakere Ranges, 9/21, D. Miller; Rotorua, 7/23, G.H.C. Wellington: Botanical Gardens (9 collections), G.H.C. Nelson: Mapua, 2/20, G.H.C. Otago: Deborah Bay, 9/26, Miss H. K. Dalrymple; Dunedin, 5/22, 9/22, 7/23, Miss H. K. Dalrymple. The characters of the species are the firm, areolate, leathery and relatively thick peridium, and the echinulate spores. Two types of spores are present in the collections examined. In the typical form the spores are commonly 10–14 mmm. in diameter, and the spines to 1.5 mmm. long; whereas in the other the spores are commonly 14–16 mmm., and in extreme cases may attain a diameter of 19 mmm., and the spines are larger, and often aggregated into the form of soldered warts. The latter is the common form in New Zealand, and is about equally distributed with the typical form in Australia. The typical plant agrees closely with the description of the species published by Coker and Couch (1928, p. 162), who have examined authentic specimens of S. flavidum. Excluded Species. Lloyd (Letter 8, p. 2, 1905; Letter 67, p. 2, 1918; and Myc. Notes, p. 1160, 1922) has recorded Scleroderma cepa Pers., S. Geaster Fr. (Myc. Notes, p. 1186, 1923) and S. verrucosum Pers. (Lyc. Aus., p. 15, 1905) from New Zealand. But from specimens at hand, and Australian collections named by him, I am convinced these records are based on misdeterminations of S. flavidum. Lloyd ignored the spore characters, and therefore was unable to distinguish (as the numerous Australian collections he misnamed show) between S. flavidum, S. cepa, S. Bovista, S. Geaster, and S. aurantium. Pisolithus Albertini and Schweinitz, Consp. fung. Lusatiae sup. Nisk crescent., p. 82, 1805. Scleroderma Pers., Syn. Meth. Fung., p. 151, 1801, pro parte. Polysaccum DC. et Desp., Rapp. Voy. bot. l'Ouest Fr., vol. 1, p. 8, 1807. Pisocarpium Link, Mag. Ges. nat. Freunde Berlin, vol. 3, p. 33, 1809. Plant consisting of a peridium supported upon a (usually) strongly developed, persistent rooting base. Peridium a single, thin, brittle and membranous layer, flaking away irregularly from the apex downwards. Gleba divided into polygonal cells by the persistent tramal plates; cells filled with the pulverulent spore mass, capillitium absent. Spores coloured, globose, verrucose. Basidia bearing 4–6 spores on short sterigmata. Habitat: Growing half buried in the ground in sandy soils. Type Species: Scleroderma tinctorium (Mich.) Pers. Distribution: Europe; North America; Africa; East Indies; Australia; New Zealand. The persistent, carbonous and brittle tramal plates and the brittle membranous peridium, which flakes away irregularly at maturity, are the characters of the genus separating it from Scleroderma. The usually persistent and well developed sterile base

Fig. 1—Scleroderma Bovista Fr. Natural size. Gregarious plants on the right. Note the almost smooth exterior of these specimens. Fig. 2.—Scleroderma flavidum E. et E. Natural size. Plant in the centre typical form, on lett weathered specimen showing stellate method of dehiscence, and on right a plant with areolate peridium.

Fig. 3.—Pisolithus tinctorius (Pers.) C. et C. Natural size. Plant on right sectioned to show the persistent glebal chambers filled with spores. Note the stout rooting base.

Fig. 4.—Pisolithus tinctorius. Reduced one-third. A plant from which the greater part of the gleba has been dissipated. Note the persistent carbonous dissepiments of the gleba and the stout, persistent rooting base. Fig. 5.—Scleroderma Bovista. Spores showing reticulations. Fig. 6.—Scleroderma flavidum. Spores showing echinulate processes. Fig. 7.—Scleroderma flavidum forma macrosporum. Spores showing their larger size and the coarse nature of the spines. Fig. 8.—Pisolithus tinctorius. Spores showing the echinulate processes. (Original) Spores × 1000.

is also a characteristic feature, as it often persists in the soil long after the gleba has been dispersed. The genus contains two, or possibly three valid species, and is represented in New Zealand by the widely distributed species described below. Pisolithus tinctorius (Micheli ex Persoon) Coker and Couch, Gast. East. United States and Canada, p. 170, 1928. Figs. 3, 4, 8. Scleroderma tinctorium (Mich.) Pers., Syn. Meth. Fung., p. 152. 1801. Pisolithus arenarius Alb. et Schw., Conspectus, p. 82, 1805. Polysaccum crassipes DC. et Desp., Rapp. Voy., vol. 1, p. 8, 1807. P. Pisocarpium Fries, Syst. Myc., vol. 3, p. 34. 1829. P. australe Lev., Ann. Sci. Nat., ser. 3, vol. 9, p. 136, 1848. P. marmoratum Berk., Jour. Linn. Soc., vol. 13, p. 133, 1872. P. album Cke. et Mass., Grev., vol. 20, p 36, 1891. Plant decidedly variable in size and shape, from 3 to 18 cm. tall, to 10 cm. diameter, with (seldom without) a firm, carbonous, well developed rooting base. Peridium a single layer, at first smooth, shining and pallid white or ochraceous, becoming brown or black, finally breaking away irregularly from the apex. Gleba divided into numerous polygonal or lenticular chambers, which are larger above and peripherally, unequal in size and shape, dissepiments carbonous, firm but brittle; chambers occupied with the pulverulent spore masses, ranging in colour from ochraceous to umber brown, sometimes tinged purple. Spores globose, 7–12 mmm. (commonly 7–9 mmm.), epispore thin, 0.5 mmm., ferruginous, covered with fine spines, which may attain a length of 1 mmm. Type Locality: Europe. Distribution: That of the genus. Auckland: Whakarewarewa, 2/27, J. B. Cleland, G.H.C.; Geyser Valley. Wairakei, 8/30, G.H.C. In New Zealand the species appears to be confined to the thermal regions of the North Island, but is abundant throughout Australia, and apparently equally common in Africa, North America, and Europe. Specimens differ greatly in size, shape, colour of the exterior, size and shape of the glebal cavities and nature of the rooting base, the only constant feature, in fact, being the spores. Most of these variants have been named at one time or another, usually from collections of single specimens; but examination of dozens of collections from Australia has led me to the opinion that it is not possible to separate any form as there are so many known intermediates as to make specific delimitation impossible. The specific name is derived from the fact that water extracts from the plant a yellow pigment which in Europe has been used by the peasants as a dye. Literature Cited. Coker, W. C. and Couch, J. N., 1928. The Gasteromycetes of the Eastern United States and Canada, 201 pp. Hollos, L. 1904. Die Gastromyceten Ungarns, 278 pp. Peyronel, B., 1922. Nuovi casi di rapporti micorizici tra Basidiomiceti e Fanerogame arboree. Bull. Soc. Bot. Ital., vol. 1, pp. 7–14.