Lichenodiplis anomalus Etayo & Pérez-Vargas, 2013

Pérez-Vargas, Israel, Etayo, Javier & Hernández-Padrón, C., 2013, New species of lichenicolous fungi from the Canary Islands, Phytotaxa 99 (2), pp. 58-64 : 60-62

Lichenodiplis anomalus Etayo & Pérez-Vargas , sp. nov. ( Fig. 2 ) MycoBank MB 800606

Similar to L. lecanorae but differs in larger lateral conidiogenous cells, with 2-4 widely spaced annellations and growing on Ochrolechia .

Type:— SPAIN. Canary Islands: La Gomera Island, Garajonay National Park, “Inmediaciones de Degollada Fría”, UTM: 266770/3113440, 1150 m, on Ochrolechia pallescens ( L.) A. Massal. on Ilex canariensis Poir. , March 2001, C. Hernández & P. L. Pérez de Paz 12739 (holotype TFC Lich!; isotype TFC Lich, herb. Etayo!).

Conidiomata pycnidial, scattered, on the host ascomata, mainly in the thalline margin, rarely in the disc, first immersed, later erumpent, unilocular, globose or slightly obpyriform, 100–150 µm diam., blackish, opening by an irregular pore. Pycnidial wall hyaline to brown, 10–15 µm thick, composed of paraplectenchymatous cells, 4–5 µm in diam., with walls ca. 1 µm. Conidiophores absent. Conidiogenous cells normally lageniform to cylindrical, lining the whole pycnidial cavity, hyaline to pale brown, discrete, smooth-walled, simple to strongly branched, 5–10 × 2.5–4 µm. In the lateral margin of the cavity, the conidiogenous cells are enlarged, with 2–4 widely spaced annellations 26–40 × 2–3.5 µm, tapering gradually to ca. 2 µm, brownish, but apically always hyaline. Conidia 1-septate, pale olivaceous brown to brown when mature, K –, smooth, ellipsoid or irregular in shape, with truncate base and a persistent marginal frill, 5.5–7 × 2.5–3.5 µm (n=25).

Etymology:— The epithet anomalus refers to the special, very long conidiogenous cells in the margin of the conidioma, which distinguish this new species from others with similar conidial size.

Distribution and ecology:— This species is known from some islands in the Canaries (La Palma and La Gomera). It grows on corticolous species of Ochrolechia in the laurel forest, a relict ecosystem of the Macaronesian Region, characterised by evergreen, glossy-leaved tree species that look alike with leaves of lauroid type. The type specimen of another Lichenodiplis species , L. lecanorae (Vouax) Dyko & D. Hawksw. is known from the Canary Islands too. However, it grows on Caloplaca cerina (Hedw.) Th. Fr.

Outside the Canary Islands, Lichenodiplis anomalus has been found in Navarra, in the north of the Iberian Peninsula, and in Chile, and so this species seems be widely distributed. The similar L. lecanorae has been recorded growing on Ochrolechia by several authors ( Berger & Diederich 1996, Kocourková 2000, Etayo & Sancho 2008). Chilean specimens identified as L. lecanorae have turned out to be the new species.

Additional specimens examined:— CHILE. Navarino, Bosque viejo del lago Róbalo, J. Etayo, A. Gómez-Bolea, U. Søchting & R. Vilches (herb. Etayo 22942); Valdivia, Región de Los Lagos, P.N. Puyehue, J. Etayo (herb. Etayo 23642); SPAIN. Canary Islands: La Gomera Island, “Tajaqué, cerca del mirador” 1300 m, J. Etayo (herb. Etayo 13201); “Hacia Tajona”, J. Etayo (herb. Etayo 2000); La Palma Island: “Los Sauces, barranco de la Herradura”, J. Etayo & P.L. Pérez de Paz (herb. Etayo 17592); Navarra: Isaba, Rincón de Belagua, J. Etayo & F.J. Arbuniés (herb. Etayo 0415); Ibidem, Selva de Aztaparreta, J. Etayo (herb. Etayo 3426)

Discussion:— The genus Lichenodiplis Dyko & D. Hawks. has a worldwide distribution and currently eleven species are accepted ( Diederich 2003, Lawrey & Diederich 2012). Although there are some differences in the complexity of the conidiogenous cells, presence of conidiophores and especially in the structure of the exciple ( Atienza et al. 2009), the distinction of Lichenodiplis from Minutoexcipula V. Atienza & E. Hawksw. is not entirely clear and some authors pointed out that more studies are needed to ascertain if the current circumscription of both genera is accurate ( Diederich 2003, 2004; Atienza et al. 2009). The new species agrees morphologically with other Lichenodiplis spp. , although the conidiogenous cells in the margin of the conidiomata, are longer than those in the centre, an unusual feature for this genus. The basal part of those cells could resemble conidiophores due to the first annellation, but are identical to the upper part with several annellations that are not found in the conidiophores ( Fig. 2 B-C-D). Thus, we consider these structures as conidiogenous cells bearing 2–4 extensions instead of conidiophores. This kind of cells has not yet been described in Lichenodiplis . However, a similar proliferating conidiogenous cell can be observed in the original description of the genus ( Fig. 1 page 54, Hawksworth & Dyko 1979).

Lichenodiplis anomalus differs from other species in the genus with 1-septate conidia mainly in the presence of the marginal conidiogenous cells and seems to be restricted to Ochrolechia species. Two Lichenodiplis species have been described growing on Pertusaria DC. : L. pertusariicola (Nyl.) Diederich and L. hawksworthii F. Berger & Diederich. The former has simple conidia and the latter has cup-shaped pycnidia and larger conidia, 8.5–13 × 4.5–5.5 µm ( Berger & Diederich 1996).

Figures

FIGURE 1. Leightoniomyces canariensis, holotype. A. Habit; scale: 0.25 mm. B. Synnema; scale: 100 µm. C-D. Conidiogenous cells and conidia; scale: 10 µm.

FIGURE 2. Lichenodiplis anomalus, holotype. A. Habit; scale: 125 µm. B. Pycnidial wall and conidiogenuous cells (in water); scale: 10 µm. C–D. Conidiogenous cells and conidia (in Congo Red); scale: 10 µm.