J. Hattori Bot. Lab. No. 85 : 245- 265 (Nov. 1998) ON THE IDENTITY AND POSITION OF PENTAGENELLA FRAGILLIMA, ROCCELLODEA NIGERRIMA, AND SOME RELATED SPECIES (ROCCELLACEAE, OPEGRAPHALES)1 2 3 2 GERHARD FOLLMANN , MARGOT SCHULZ , AND BIRGIT WERNER INTRODUCTION Pentagenella fragillima was described from Chile by Darbishire (1897) and Roccellodea nigerrima from the Galapagos Islands by the same author ( 1932). Because of apparently missing type material, both Roccellaceae were excluded from a cladistical treatment of the family as critical taxa of uncertain position by Tehler (1990), and Weber (1986) listed the second one under "Rejected reports, synonyms, and misapplied names" in his catalogue of Galapagos lichens. On the other side, lichen samples corresponding largely to Darbishire's descriptions of P. fragillima and R. nigerrima growing close to their supposed type localities were repeatedly used for chemo­ taxonomical studies by Huneck & Follmann (1967), Follmann & Huneck (1969), Follmann et al. (1993), etc. and cited in floral inventories and sociological registers (i.a., Follmann 1962, 1964, 1967, 1995, 1997). Meanwhile, the type specimens were located in the herbaria of the National Museum of Natural History at Paris (PC) and of the Department of Botany of the University of Bristol (BRIST), respectively. The following revision, which includes some related taxa, was carried out to bring this unsatisfactory and impeding situation to an end. MATERIAL AND METHODS For the present check-up, specimens of Roccellaceae preserved in the public herbaria at Boulder (COLO), Bristol (BRIST), Geneva (G), Helsinki (H), London (BM), Lund (LD), Paris (PC), Santa Cruz de Tenerife (TFMC), Stockholm (S), Uppsala (UPS), Vienna (W), and Washington (US) were used. In addition, supplementary field 1 In memory of Otto Vernon Darbishire (1870- 1934) on occasion of the IOOth anm­ versary of the publication of his "Monographia Roccelleorum" (1898) which - despite some misunderstandings and shortcomings concerning the state of knowledge of the period - laid the foundations for many directive biosystematical and geobotanical studies on one of the most peculiar lichen families. 2 Botanical Institute, University of Cologne, Gyrhofstr. 15, D-50931 Cologne, Germany. 3 Institute for Agricultural Botany, University of Bonn, Meckenheimer Allee, D-53115 Bonn, Germany. 246 J. Ha1tori Bot. Lab. No. 85 I 9 9 8 studies were carried out in the Atacama Desert (Chile) and on the Galapagos Islands (Ecuador) by the authors at regular intervals from 1989 to 1997. All lichen samples were subjected to the conventional spot-tests (ST), anatomical (LM), microcrystallographical (MC), thin layer chromatographical (TLC), and high performance liquid chromatographical (HPLC) analyses, if necessary completed by UV spectroscopy (UVS) and melting point determinations (MP). For the anatomical descriptions, freezing microtome sections were used, the corresponding measurements being made with preparations in water. The standard methods for colour reactions, extraction procedures, MC, TLC, and MP described by Huneck & Yoshimura (1996) were followed, but to allow direct comparisons with former results HPLC and UVS were performed according to Follmann et al. ( 1994) with the aid of Beckman's "System Gold" and auxiliary equipment. For co-chromatographical verifications (TLC, HPLC), the Roccellaceae analysed by Follmann et al. (1993) were available, each treatment being repeated at least five times. Finally, all morphological and chemical data were evaluated numerically and confirmed statistically (Forey et al. 1994, Pankhurst 1991 ). R ESULTS ANO DISCUSSION Pentagenella fragillima Darbishire ( 1897) Roccella fragilissima Montagne in herb. (s.a.). Roccella fragillima (Darbishire) Choisy, comb. inval. ( 1957). As already noted by Darbishire (1898 a), the type collection of Pentagenella fragillima (Herb. C. Montagne, s.a., s.n., PC, actually on loan at KOELN) un­ fortunately consists of a few fragments of a fruticose thallus only, the largest being 35 mm long and in places 5 mm wide, but the others being much smaller. Except Darbishire's revision slip of 1897, there are two labels of Montagne's hand which read as follows: 1. " Rocce/la fragilissima Mont. an R. gracilis Bory?, Coquimbo, Chili, M. Webb" and 2. " Roccellafragilissima Mont. ined. ou a R. taeniata Mont. ined. diversa? Coquimbo in Chile, corn. am. Webb" . R. gracilis Bory is known to be a synonym of R. phycopsis Ach. , and R. taeniata Mont. in herb. belongs to R. portentosa (Mont.) Darb. Consequently, both alternatives can be neglected in virtue of various deviating ch aracters. Deduced from the dimensions of the fragments, the thallus of Pentagenella fragi/lima Darb. might have been 10 to 15 cm high , and the fragile and rigid consistence of the sections points to an upright growth. To judge from a computer simulation, the habit came nearer to that of the African Roccella hypomecha (Ach.) Bory (see Follmann et al. 1994, Fig. 3) than that of the South American Roccel/a portentosa (Mont.) Darb. as insinuated by Darbishire (1898 a). Nevertheless, it should be taken into account that no trace of a holdfast or protothallus could be found, characters included in the generic protologue by the same author (I.e.), but he was certainly right to conclude from the few references at hand that the taxon occurred on rocky ground. Beyond that, the detection of sea salt on the cortex points to a halophytic behaviour typical for most Roccellaceae. G. FOLLMANN et al. : Pentagenella and Roccellodea 247 Fig. I. Type material of Pentagenel/a fragil/ima Darb. with (A) part of largest fragment, note crateriform pycnidia (diam. of branch 1.5 mm) and (B) plate-shaped pseudocarps (diam. of largest one 1.3 mm [phot. B. Werner]). Wherever possible, the following abbreviated description, focused on essential characters, combines Darbishire's (1897, 1898 a, b) with our own observations: Thallus fruticose, podetia terete (mean diam. 1.2 mm) to applanate (about 0. 7 x 3.0 mm), ash-grey, rough and pruinose, without isidia or soralia, dichotomously branched, extremely fragile (Fig. I); cortex (mean diam. 75 µm) with anticlinally arranged, smooth hyphae (mean diam. 4 µm), in the light outer part more loosely packed, in the darker inner part compact, anastomosing, and interspersed by different types of crystals including calcium oxalate, brownish, granular surface gel only in the inner part; algal laY.er continuous (mean diam. 50 µm), trentepohliaceous phycobionts often deformed, solitary (mean diam. 12 µm) or in short fi laments, covered by hyphal appressoria; medulla light (mean diam. 70 µm), hypomedulla brown, both formed by more or less periclinal strands of conglutinate, verrucose, thick-walled, anastomosing hyphae difficult to distinguish, hypomedullary strands interspersed by brownish, granular, 248 J. Hattori Bot. Lab. No. 85 I 9 9 8 Fig. 2. Type material of Pentagenella fragillima Darb. with discothecia on pseudopodetium-like excrescences, droplets consisting of glue used to fix fragment on herbarium sheet (diam. of ascocarp below droplet 0.4mm [phot. B. Werner]). crystalliferous thallus gel; cortex, medulla, and thalline margin of pseudothecia C+ pink (fugitive), K+ ochre, P+ orange-red, containing erythrin and protocetraric acid (Fig. 3A). Lateral and lamina) ascomata apparently numerous, but supposed larger, thallus-coloured "discocarps" (Fig. 1) in reality plate-shaped vegetative excrescences (mean diam. 1.2 mm) normally bearing several lecanorine pseudothecia (Fig. 2): Roundish, sessile, base barely constricted, plane to subconvex (mean diam. 0.4mm), disk blackish, pruinose, thalline margin relatively thick, crenated, corticate, algiferous; epithecium brown, granular (mean diam. 30 µm), hyphae cylindrical, branched, intertwined; proper exciple a parathecium, dark-brown (mean diam. 45 µm), hyphae slightly clavate; hypothecium brown, not extending down into the medulla (mean diam. 90 µm), hyphae densely covered by crystalloids and granula; hymenium with multiascal locules, pluricarpocentral, hyaline (mean diam. 75 µm), subhymenium G. FOLLMANN et al.: Pentagenella and Rocce/lodea 249 0,20 2 A 0,15 ~ ~ 0,10 .0 0 rJJ .0 "' 0,05 0,00 0 10 20 30 40 50 60 70 0' 20 .----rr-..----,--..----,--..----,--..----,--..----,--~--,--.---~ 4 B 0, 15 ~ ~ 0,10 .0 0 rJJ 3 .0 "' 0,05 0,00 0 10 20 30 40 50 60 70 retention time [min] Fig. 3. HPLC-profiles (reversed phase) of acetone extracts of type material of (A) Pentagenella fragillima Darb. and (B) lngaderia friabillima Follm. & M. Schulz (I = erythrin, 2 = protocetraric acid, 3 = conpsoromic acid, 4 = psoromic acid [prep. B. Werner]). distinct, light-brown (mean diam. 25 µm), hamathecium paraphysoidal, paraphysoids septate, branched, anastomosing, asci clavate (about 18 x 60 µm), apical cap com­ paratively inconspicuous, amyloid (Kl + blue), eight-spored, ascospores biseriate,. colourless, fusiform, straight, relatively thin-walled, three-septate (about 6 x 19 µm); pycnidia numerous, externally crateriform (ostiole about 50 µm in diam.), corpus globular, black (mean diam. 90 µm), pynoconidia "exobasidial", filiform, curved (about 0.8 x 21 µm). 250 J. Hattori Bot. Lab. No. 85 I 9 9 8 The exceptional brittleness of the dry branches of Pentagenella fragillima Darb. is undoubtedly related to the deposition of unusual quantities of crystalloids and granules in virtually all layers. The first are largely consisting of protocetraric acid determined in situ by crystal form, colour reactions, and solubility in various solvents.