Two New Species of Hypotrachyna (Lichenes) from India

Abstract

Two new species of Hypotrachyna are described from the Western Ghats region of India. Hypotrachyna awasthii Hale & Patwardhan, sp. nov. (FIG. 1) Thallus corticola, laxe adnatus, 6-10 cm diametro, albido-cinereus, lobis latis, subirregularibus, apice rotundatus, usque ad 1 cm latis, isidiatis, isidiis densis, simplicibus vel ramosis, cylindricis, 0.1-0.2 mm diametro, 0.5 mm altis; superne planus, nitidus, cortex superior 12-14 /m crassus, stratum gonidiale 16-18 /m crassum, medulla alba, 90-110 [tm crassa, cortex inferior 16-18 p/m crassus; subtus niger, modice rhizinosus, rhizinis sparse dichotome ramosis. Apothecia (ex coll. Hale & Patwardhan 40070) rara, adnata, 1.0-2.5 mm diametro; hymenium 50-60 /m altum, sporis octonis, simplicibus, 8 X 10 p/m. Holotype: India. Wilson Point, Mahabaleshwar, Maharashtra, elevation 1580 m, Awasthi 4041, 14 October 1959 (AWASTHI HERBARIUM; isotype in us). Chemistry: Atranorin, norstictic acid, salazinic acid (at times trace only). Additional specimens examined. India, Mahabaleshwar, Maharashtra, Degelius As-48 (DEGELIUS HERBARIUM), Hale & Patwardhan 40070 (us and M.A.C.S. HERBARIUM, POONA). This species was initially identified as Parmelia wallichiana Taylor, which has simple rhizines, marginal cilia, and salazinic acid alone. Careful examination of ample material from Mahabaleshwar, however, showed that the rhizines are dichotomously branched, placing the species in the genus Hypotrachyna (Vainio) Hale. The combination of acids is typical of Old World members of the genus. Comparable New World species would have usnic acid instead of atranorin in the cortex. The one exception, H. rhabdiformis (Kurok.) Hale, has dense rhizines and sublinear lobes. Parmelia wallichiana also occurs rather widely in India and care should be taken to separate it from Hypotrachyna awasthii. This new species grows abundantly on trunks of small trees, both planted and naturally growing, in open areas on the Mahabaleshwar plateau, a region of low but dense rain forest. Hypotrachyna dodapetta Hale & Patwardhan, sp. nov. (FIG. 2) Thallus corticola, laxe adnatus, ad 12 cm diametro, cinereo-albus, lobis subirregularibus, apice rotundatis, 0.5-1.0 cm latis; superne planus, nitidus, mox valde pustulatus, pustulis fragilibus, erumptentibus, esorediatis; cortex superior 11-12 [km crassus, stratum gonidiale 22-24 [tm crassum, medulla alba, 90-110 [tm crassa, cortex inferior 8-10 /m crassus; subtus niger vel marginem versus castaneus, modice rhizinosus, rhizinis dense dichotome ramosis. Apothecia ignota. Holotype: India. On roadside Cupressus on road to Dodapetta, elevation about 2600 m, Nilgiri Hills, Tamil Nadu, Hale & Patwardhan 40218, 8 November 1973 (us, holotype; isotypes in AWASTHI HERBARIUM and the M.A.S.C. HERBARIUM, POONA). Chemistry: Atranorin, salazinic acid, and traces of norstictic acid. This robust species of Hypotrachyna has, as do many Old World species, rather broad subirregular lobes, in contrast to the more usual narrow sublinear lobes found in most New World species. The closest relative is another Indian endemic, H. thryptica (Hale) Hale, known only from Kerala. It has a much smaller, more fragile thallus and This content downloaded from 157.55.39.231 on Thu, 06 Oct 2016 04:01:15 UTC All use subject to http://about.jstor.org/terms 638 THE BRYOLOGIST [Volume 77