FOLIICOLOUS LICHENS OF THE FIJI ISLANDS*

Eighteen species of foliicolous lichens have been mentioned earlier from the Fiji Islands in various literature sources and based on collections since 1860. Current records originate from the collections of Göran Thor from 1985 and Sarolta and Tamás Pócs from 2003. G. Thor visited lowland rainforests of Island Viti Levu, S. and T. Pócs collected also in higher elevations (up to ca 1,000 m) in submontane, montane and montane mossy (cloud) forests on Kadavu, Taveuni and Viti Levu Islands. These relatively small collections (of ca 300 and 150 leaves, respectively) resulted in 78 species of the 85 lichen species known today, among them 67 species are new for the foliicolous lichen flora of the area in this publication. New taxa described are Phylloblastia taveuniensis Farkas, Porina kadavuensis Farkas, furthermore the genus Tamasia Far-kas (Ramalinaceae) and species Tamasia fijiensis Farkas containing cyanobacterial photobiont.


INTRODUCTION
The remote Fiji Islands involves more than 330 islands in the South Pacific Ocean.About 110 of them are permanently inhabited.The majority, 87% of the Fijians live on the two major islands, Viti Levu and Vanua Levu.Taveuni and Kadavu are the third and fourth largest islands.Half of the area of the mountainous islands is covered by tropical rainforests with about 60% endemic plants.The highest peaks are around 1,300 m.Bottled water and sugar export and growing tourism are the most important for the economy of Fiji (http://en.wikipedia.org/wiki/Fiji).Therefore the exploration of the biodiversity of the Fiji Islands is maybe in the last minute before increasing human impact would have a damaging effect on its unique natural biota.Polynesia-Micronesia hotspot -including the Fiji Islands -is considered as one of the 35 global biodiversity hotspots (Mittelmeier et al. 2005).
Lichens, just as other cryptogams of Fiji are insufficiently known (Konrat et al. 2011, Lücking et al. 2000), though their better knowledge is highly required due to their importance for nature conservancy or bioindication value.
Foliicolous lichens are sensitive organisms to climate change and disturbance, excellent indicators of various types of rainforests (Lücking 1997c(Lücking , 2008b)).
Lichen floristical data are compiled by Elix andMcCarthy (1998, 2008).Further records were published by Lumbsch et al. (2009Lumbsch et al. ( , 2011)).A poster was presented on preliminary results based on foliicolous lichen collections studied below and a short abstract without list of species was published (Farkas 2008).In 2008, 79 species known by that time were reported.However, this number had to be revised due to the subsequent publications (Lücking 2008a, Lumbsch et al. 2011).
These relatively small collections (of about 300 and 150 leaves, respectively) resulted in 78 foliicolous lichen species.Among them 67 species are new today for the foliicolous lichen flora of the area of the Fiji Islands.Three species and a genus are new for science.Farkas,spec. nova (Fig. 2) MycoBank No.: MB 847541

Phylloblastia taveuniensis
It differs from P. dolichospora by the considerably smaller perithecia and ascospores and the fewer septa of ascospores.Thallus epiphyllous, formed by small round thallus patches, partly becoming continuous, ca 2 cm wide, pale green.The round scales of ca 0.10-0.15mm diam.serve as isidia (schizidia) (see Fig. 2A, B).The outline of the thallus is irregular, a dark prothallus is seen around it.
Perithecia 0.10-0.25 mm, reddish brown, brown, hemispherical to cylindrical, slightly constricted at base.The dark, brownish black involucrellum is entirely surrounding the hymenium, the exciple and involucrellum cannot be separated completely.A thalline layer covering the involucrellum is so thin (ca 10-15 µm) that the perithecium is still seen dark from above, only the constriction at base appears in the colour of the thallus (Fig. 2C).Ascospores colourless, 65-75 × 6-7 µm, pointed at both ends, 25-33-septate with few longitudinal septa (Fig. 2D).
Distribution and ecology.Known from the Fiji Islands only, growing on leaves of a vascular plant.
Distribution and ecology.Known from the Fiji Islands, growing on leaves of vascular plants.

THE NEW GENUS AND SPECIES
Tamasia Farkas,gen. nov. MycoBank No.: MB 804957 The new genus belongs to the family Ramalinaceae.It differs from Bacidina by the wider 1-septate ascospores, characteristic Tamasia type ascus apex, closest to Lecidella type and the usually unbranched, but seldom near to apex slightly branching paraphyses.It differs from Megalaria by different pigmentation of the hymenium, the structure of the exciple and the slightly constricted, thin-walled ascospores.
Etymology.The generic name is derived from the first name of Tamás Pócs Hungarian academician, worldwide known expert of tropical plants, researcher of cryptogamic organisms, and who is especially fond of cyanobacteria.
Conidiomata not observed.Chemistry: no substances detected by HPTLC.Distribution and ecology.So far with Palaeotropical distribution as known only from the Fiji Islands, characterised by foliicolous growth.
Discussion.Similarly looking species are Bacidina mirabilis (Vězda) Vězda (Vězda 1991: 432) and Fellhanera parvula (Vězda) Vězda (Vězda 1986: 214), however both species differ in various characters and combination of characters.Both species have paraplectenchymatous exciple, ascospores of similar size, but max.2.5 µm wide according to the original descriptions.Nevertheless, the original illustrations by Vězda (Catillaria parvula Vězda -Vězda 1974: 176 and Catillaria mirabilis Vězda -Vězda 1980: 80) at both species show some wider, shorter ascospores too, which have similar shape with those of ascospores of the here described lichen.Both species have simple (to slightly branched) paraphyses.However, at the Fellhanera species there is no thickening at the apex of paraphyses and they are characterised by Byssoloma type ascus apex (sensu Hafellner 1984) and the paraphyses at Bacidina are more-orless evenly thick and has no branching, also the ascus apex is different (tholus with conical axial mass).The size of apothecia is different too, at F. parvula it is slightly smaller and at B. mirabilis slightly bigger than those of the new species.The features of thalli are not comparable due to the different photobionts.The thallus of T. fijiensis is violet due to the colour of the cyanobacteria and thus different from the earlier described Bacidina simplex f. cyanophila Lücking (2008a: 603) which has aerugineus thallus consisting of Rhizonema goniocystangia (cf.Lücking et al. 2009).Ascospores of the new species seldom seem to be 3-septate at lower magnification, but it is only due to a surface ornamentation.Exclusively 1-septate ascospores were found at large (100×) magnification.A free-living filamentous scytonematoid cyanobacterium of (5-)7.5-8.3 × 3.7-5 µm cells and the lichenised Cyphellostereum cf.phyllogenum (containing Rhizonema sp.) was also present on the same leaf (cf.Lücking 2008a: 783).

CHECKLIST OF THE FOLIICOLOUS LICHEN SPECIES OF THE FIJI ISLANDS
Based on literature sources and collections studied so far, a checklist of 85 species currently known from the Fiji Islands is compiled.

DISCUSSION
Nine species of foliicolous lichens have been known from the Fiji Islands since 1860 until the beginning of this century (Santesson 1952, Santesson andTibell 1988).Then, according to the poster presentation by Farkas (2008) 70 species were new for the foliicolous lichen flora of the Islands.It was followed by the monograph of Lücking (2008a) mentioning one additional species and a paper of Lumbsch et al. (2011), which contained 8 foliicolous lichen species from their own collections.Four of those were overlapping with the species listed on the poster and 4 were newly reported.Since the published abstract of the poster did not contain the list of species, the results had to be re-evaluated according to the subsequent publications.
Though the knowledge on the foliicolous lichen flora of the Fiji Islands increased considerably due to these collections, further species are expected to be described in the future.Some lichens were impossible to be identified due to the amount occurred in the collections studied here.A more detailed systematic investigation is necessary to reveal the entire number of foliicolous lichen species living on the islands of Fiji.For a comparison of its foliicolous lichen biota, data from the neighbouring major lichenogeographical regions can be considered.The larger Malesian region holds 290 foliicolous lichen species, the also larger Polynesian region is characterised by only 36 species, while the smaller Neocaledonian region is richer (111) in species (cf.Lücking 2003 andFig. 42 in Lücking 2008a).A further biogeographical assessment of the species known from Fiji is necessary in a following compilation.*