Notes on Graphidaceae in Macaronesia, with Descriptions of Four New Species

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Introduction
An extensive field study of lichens and lichenicolous fungi in Macaronesia, in particular the Azores and Madeira (Figure 1), by the first author showed that the lichen diversity of these islands is still incompletely known [1][2][3]. Here we present results for the family Graphidaceae. The presence of this conspicuous family in Macaronesia has already received considerable attention. Records are summarized in various checklists [4][5][6]. Lücking & Breuss [7] published a key for the thelotremoid species in Macaronesia and accepted nine species. Our new fieldwork contributed in particular to the genera Fissurina, Graphis, and Topeliopsis and the results are presented here. For each species the presence on the Azores archipelago (A), the Madeira archipelago (M) and the Canary Islands (C) is indicated.

Introduction
An extensive field study of lichens and lichenicolous fungi in Macaronesia, in particular the Azores and Madeira (Figure 1), by the first author showed that the lichen diversity of these islands is still incompletely known [1][2][3]. Here we present results for the family Graphidaceae. The presence of this conspicuous family in Macaronesia has already received considerable attention. Records are summarized in various checklists [4][5][6]. Lücking & Breuss [7] published a key for the thelotremoid species in Macaronesia and accepted nine species. Our new fieldwork contributed in particular to the genera Fissurina, Graphis, and Topeliopsis and the results are presented here. For each species the presence on the Azores archipelago (A), the Madeira archipelago (M) and the Canary Islands (C) is indicated.  Diagnosis: Most similar to Fissurina deficiens but different in the whitish vs. brownish thallus, the often slightly gaping vs. concealed disc, and the smaller ascospores.
Holotype: Portugal Etymology: The epithet refers to the habitus of the apothecia, especially the always black-colored labia.
Thallus epiperidermal, corticate, smooth, whitish; Ascomata lirelline, labia apically distinctly carbonized, apically blackened when seen from above, with short, smooth pe- Diagnosis: Most similar to Fissurina deficiens but different in the whitish vs. brownish thallus, the often slightly gaping vs. concealed disc, and the smaller ascospores.
Holotype: Portugal Etymology: The epithet refers to the habitus of the apothecia, especially the always black-colored labia.

Notes:
The name Fissurina dumastii was mentioned from Terceira [12], without any detail about its morphology. In the literature, descriptions are rather confusing. In [13], the species has immersed lirellae of 1-3 × 0.05-0.1 mm and ascospores of 18-20 × 8-10 µm, but in [9] sessile lirellae (especially visible in Figure 217) of 1-5 × 0.2-0.3 mm and ascospores of 11-18 × 5-6 µm. According to the rather depauperate type material from South America, the species is characterized by mostly immersed lirellae with thin labia (fissurinoid) and a somewhat gaping disc, apically spinulose paraphyses, and weakly amyloid ascospores [9]. As a consequence, much of the material identified with that name may not represent that species. Thus far, only two other species have been described with similar morphology but smooth paraphyses, F. amazonica M. Cáceres, Aptroot & Lücking from Brazil and F. coarctata Makhija & Adaw. from India, both with rather short lirellae [14,15]. We have several specimens that might belong to F. dumastii, but most of them are not well developed, with degenerated hymenia. Only one shows properly developed paraphyses and ascospores. It has lirellae 0.5-5 mm long, curved and often branched, a hymenium 90-110 µm high, and ascospores 12-15 × 8-9 µm in size. The original description [16] gives the type as "Habitat in America, ad corticem Cinchonae lanceolatae (Mutis.)". This indicates that the type is from South America, collected by Mutis; Mutis lived in Colombia, so the type specimen is most probably from Colombia, not USA as indicated in the Index Fungorum.  Notes: This material comes close to Fissurina instabilis in having lirellae with thickened labia (hemithecioid) and muriform ascospores about 20-30 × 9-12 µm. The latter differs, however, in the whitish lirellae contrasting with the olive-green thallus. According to [9], psoromic acid is supposed to be sometimes present in F. instabilis; however, this likely refers to two other species with similar morphology and psoromic acid chemistry,  Notes: This material comes close to Fissurina instabilis in having lirellae with thickened labia (hemithecioid) and muriform ascospores about 20-30 × 9-12 µm. The latter differs, however, in the whitish lirellae contrasting with the olive-green thallus. According to [9], psoromic acid is supposed to be sometimes present in F. instabilis; however, this likely refers to two other species with similar morphology and psoromic acid chemistry, namely F. globulifica (Nyl.) Staiger     Notes: The present material is quite unique in combining hemithecioid lirellae with apical carbonization with three-septate ascospores and a stictic acid chemistry. It is somewhat similar to Fissurina consentanea, but differs in the apically carbonized labia. Only two species in the genus share these features: F. inquinata C. Knight & Mitt. from New Zealand (synonym: F. comparilis var. nigririmis Nyl.) and F. khasiana Makhija & Adaw. from India. Morphologically, the present material is close to F. khasiana in the labia being largely covered by thallus and with a slightly gaping disc, but we have been unable to obtain authentic material of the latter to confirm this identification. Fissurina quadrispora Kalb A−, C−, M+. Earlier reports: [9,17]. A distinctive species by the content of psoromic acid, the four-spored asci and the ascospores three-septate, 22-28 × 10-13 µm, known from a single specimen from Madeira so far, and not present among our Macaronesian material.

Allographa and Graphis
In the checklist of [6], four species currently considered to belong to Graphis (including Allographa) are listed: Graphina anguina from Madeira [18], Graphis elegans (Borrer ex Sm.) Ach. from all three island groups, Graphis lineola from Madeira [18], given as doubtful, and Graphis scripta (L.) Ach. from all three island groups. Graphis elegans and Graphis scripta are also recorded from the Azores by [4]. The report of G. anguina most likely follows the common misinterpretation of this species by European lichenologists during the 20th century. This was corrected by [9] to Graphis britannica Staiger and subsequently to G. inustuloides Lücking [19]. The report of G. lineola by [11] was published with hesitation. Therefore, the species is included below provisionally, awaiting confirmation. This makes it so that only three species of Graphis can be considered as known so far from Macaronesia. They are the same species as reported elsewhere in Western Europe and it can be assumed that this reflects the experience of the European lichenologists who visited the islands. However, ref. [20] have shown that the number of Graphis species in SW Europe is underestimated. The same might well be the case for Macaronesia, and this was confirmed by the examination of numerous Macaronesian Graphis specimens from the herbarium of the first author. Besides G. elegans and G. scripta, G. chlorotica, G. furcata, G. lineola, G. longissima, as well as Allographa ruiziana and A. verminosa are present. Short descriptions of all taxa are given below.
The identification of Graphis species is somewhat tricky because the ascocarps show considerable changes during their development, and well-developed specimens in good condition are needed for easy identification. Initially the ascocarps develop in the host bark. They therefore have a lateral thalline margin when they emerge. This thalline margin may be permanent and cover the lirellae more or less when fully developed, or it may disappear in an early stage. Another age-dependent character is the striation of the exciple. It is seemingly caused by a regeneration of the excipulum, and accordingly still absent in young lirellae. The character of ascospore color can also be misleading. In species of Graphis the ascospores are colorless, while in, e.g., Phaeographis, the spores assume a pale gray color after a colorless juvenile stage. However, in Graphis, overripe and degenerating spores may also become gray. Notably in European samples, the ascocarps tend to contain many such gray, more or less shriveled spores, while colorless, well-developed spores may be scarce. Unfortunately, Graphis samples are often without well-developed ascospores, and for a considerable part of our available material the identification remains provisional. See [21] for more details on Graphis. ascospores, and for a considerable part of our available material the identification remains provisional. See [21] for more details on Graphis.
Notes: This is the first report from Macaronesia of this pantropical species [21]. The specimen deviates slightly because the striae on the excipulum are scarce and the central parts of the lirellae are not swollen and rather scarcely striate.  Thallus with norstictic acid; ascocarps sessile, without thalline margin except when young, about 0.3 mm wide without thalline margin, with entire or in older lirellae striate, laterally to (almost) completely carbonized excipulum, and with a concealed disc; hymenium clear; ascospores bacillar, ca. 60-75 × 15-17 µm, ca. 12-loculate, with thick lateral wall and rounded lumina. Thallus without lichen substances; ascocarps erumpent with lateral thalline margin, with striate, apically carbonized excipulum, and with a concealed disc; hymenium clear; ascospores bacillar, ca. 45 × 12 µm, 10-loculate, with lenticular lumina and a thin outer wall.
Notes: This is the first report from Macaronesia of this pantropical species [21]. The specimen deviates slightly because the striae on the excipulum are scarce and the central parts of the lirellae are not swollen and rather scarcely striate. Thallus without lichen substances; ascocarps erumpent with lateral thalline margin, with striate, apically carbonized excipulum, and with a concealed disc; hymenium clear; ascospores bacillar, ca. 45 × 12 µm, 10-loculate, with lenticular lumina and a thin outer wall.
Notes: This is the first report from Macaronesia of this pantropical species [21]. The specimen deviates slightly because the striae on the excipulum are scarce and the central parts of the lirellae are not swollen and rather scarcely striate.  Thallus with norstictic acid; ascocarps sessile, without thalline margin except when young, about 0.3 mm wide without thalline margin, with entire or in older lirellae striate, laterally to (almost) completely carbonized excipulum, and with a concealed disc; hymenium clear; ascospores bacillar, ca. 60-75 × 15-17 µm, ca. 12-loculate, with thick lateral wall and rounded lumina. Thallus with norstictic acid; ascocarps sessile, without thalline margin except when young, about 0.3 mm wide without thalline margin, with entire or in older lirellae striate, laterally to (almost) completely carbonized excipulum, and with a concealed disc; hyme-nium clear; ascospores bacillar, ca. 60-75 × 15-17 µm, ca. 12-loculate, with thick lateral wall and rounded lumina.
Notes: For earlier reports see [6,11]. The presence of norstictic acid is best demonstrated by adding K to a (thick) section. Under the microscope, yellow clouds will develop, which condensate into numerous small red crystals. A K-reaction directly on the thallus often remains uncertain.  Notes: For earlier reports see [6,11]. The presence of norstictic acid is best demonstrated by adding K to a (thick) section. Under the microscope, yellow clouds will develop, which condensate into numerous small red crystals. A K-reaction directly on the thallus often remains uncertain.
Notes: A widespread tropical species, which is reported here for the first time from  Thallus without lichen substances; ascocarps erumpent, about 0.2 mm wide including the thalline margin, slightly sinuous, with gradually raising, lateral thalline margin and the exposed part of the exciple narrow, black, with entire, laterally carbonized excipulum, and with a concealed disc; hymenium clear; ascospores bacillar, ca. eight per ascus, 25 × 8 µm, 6-8-loculate, with lenticular lumina.
Notes: A widespread tropical species, which is reported here for the first time from Macaronesia. Earlier reports: [32]. This species was published after the key of [7]. It is said to be similar to T. lepadinum from which it differs by a yellow, K+ red medulla.
This new Topeliopsis is easily overlooked for T. azorica, especially in the field. Therefore, differences about ascospores and chemistry should be checked. T. azorica is known from the same island (Pico) Macaronesia   1  Thallus corticolous  2  1 Thallus saxicolous, terricolous, or lichenicolous 24 2

Conclusions
The islands of Macaronesia are popular among Western European naturalists and seemingly everywhere lichens were collected. However, these were published rather incidentally, and no thorough revision was ever made for most of the lichen groups. We revised the family Graphidaceae, excluding the thelotremoid species, and found that the most diverse genus of the family, Graphis, is represented by seven species, three not known from the region before, and none endemic. Two species of the recently segregated genus Allographa are also new records. The inconspicuous genus Fissurina was evidently much undercollected, and we recognized eight species, several are additional, not known before, and all present in our own collections. Three of the Fissurina species were undescribed and endemic to the Azores. The genus Topeliopsis was known from the Azores with one endemic species, Topeliopsis azorica, and we recognized a further endemic species. Altogether the family Graphidaceae is now known to be represented by 44 species, recorded from all three archipelagos, but mainly the Azores.