Taxonomic study on the lichen genus coccocarpia (lecanorales, ascomycota) in South Korea.

Three species of Coccocarpia have been reported from Korean Peninsular. However, there was no revisional study on this genus before. After careful examination of the specimens deposited in the Korean Lichen Research Institute (KoLRI) and collected from main mountain areas of Korea, two species of Coccocarpia, C. palmicola and C. erythroxyli, have been revealed to occur and confirmed in South Korea. The presence and absence of isidia and apothecia are the most important characters for the South Korean species. We provide the detailed description and illustration of the available two species. A key to the species is also provided.

The lichen genus Coccocarpia Pers. belongs to the family Coccocarpiaceae Henssen. The genus was first recognized by Person in 1826. In the end of 19th century, most taxa of Coccocarpia were described. Several new species were added in 20th century. The important work in the history of Coccocarpia was done by Henssen (1963). After the detailed investigation of the ascocarps, he separated it from Pannariaceae. The family contains only one genus and 21 species, widely distributed in tropical and temperate regions. It has the foliose thallus composed of a prominent cortex and white medulla, and most of them have the distinctly foliose and lobate thallus. Most of the species can be distinguished by the presence of the isidia, apothecia and the shape of the isidia. Although there were many reports on the study of Coccocarpia (Arvidsson, 1983, 1992; Brodo et al., 2001; Hessen, 1963), almost no expert study on Coccocarpia had been conducted in Korea until the macrolichen flora of South Korea was published (Park, 1990). In her paper, 3 species of Coccocarpia were reported with brief description of each species and a key to the species. The aim of this study is to evaluate the importance of the taxonomic characters, and to do detailed phenotypic and phylogenetic investigation on the species which have not been done in Korea so far.

Materials and Methods

Morphological and anatomical examination

Fifty-one lichen specimens of Coccocarpia from South Korea were examined and are deposited in KoLRI (Korean Lichen Research Institute) (Table 1). External morphologic descriptions were based on the air-dried materials, all of them were observed under the stereomicroscope (Nikon SMZ1500). Sections were made with a razor blade under the stereomicroscope. Samples were mounted with the GAW (glycerol : ethanol : water = 1 : 1 : 1), and observed using compound microscope (Olympus BX50). The chemical characters were examined by medullar color reaction (KOH, CaCl2O2, and P-phenylenediamine) and thin layer chromatography (Culberson, 1972).

Table 1

Specimens used for taxonomical study of South Korean Coccocarpia in this study

aMt. Baekwoon, Mt. Cheonchuk, Mt. Cheontae, Mt. Dukyoo, Mt. Halla, Mt. Hukseok, Mt. Jiri, Mt. Jogae, mt. Jorung, Mt. Jumbong, Mt. Juwang, Mt. Naejang, Mt. Odae, Mt. Sobaek, Mt. Sorak, Mt. Wolchul, Mt. Wolak.

*Specimens used for DNA sequencing analysis.

DNA extraction and nrDNA amplification

Ten representative specimens were used for ITS sequence analysis. Lichen thalli were fractioned with cryo-tissue-crasher (SK200, Tokken, Japan). Total DNA was extracted directly from whole thalli according to Ekman (1999) with DNeasy Plant Mini Kit (QIAGEN, Germany), then purified by PCRquick-spin™ PCR Product Purification Kit (iNtRON Biotechnology, INC.). The nrDNA ITS region (ITS1-5.8S-ITS2) was amplified by PCR. Primers for amplification were: ITS1F (5'-CTTGGTCATTTACAGGAAGTAA-3'; Gardes and Bruns, 1993) and ITS4A (5'-ATTTGAGCTCTTCCCGCTTCA-3'; White et al., 1990). Previously described conditions by Arup (2002) have been used for PCR amplification and cycle sequencing.

Sequencing and phylogenetic analysis

PCR products were sequenced by ABI 3700 automated DNA Sequencer in NICEM at Seoul National University. The software Mega3.1 (Kumar et al., 2004) was used to do the sequence analyzing. Neighbor-joining was chosen to construct the phylogenetic tree: Gaps data was pairwise deletion, and model was kimura 2-parameter, test of inferred phylogeny was 1000 times of boostrap. Leptogium lichenoides (GenBank accession number: DQ466041) and Pannaria rubiginosa (AF429280) were chosen as the outgroups.

Results and Discussion

Among the 3 species of Coccocarpia previously reported in South Korea, only C. palmicola (Spreng.) Arv. & D. J. Galloway and C. erythroxyli (Spreng.) Swinscow & Krog were confirmed in this study. The main character of C. palmicola is the presence of cylindrical isidia, which easily distinguished it from C. erythroxyli having no isidia. Presence of apothecia can be an additional character to separate them. Black and biatorine apothecia present in most of C. erythroxyli specimens, but absent in C. palmicola. The NJ consensus tree constructed by Mega3.1 is shown in Fig. 1. According to the tree, each species finely assembled together and this proved that isidia is the key character to separate the two species.

Fig. 1

NJ consensus tree based on nrDNA ITS sequence, numbers in each bootstrap support value. Nucleotide: Kimura 2-parameter, pairwise: deletion, bootstrap = 1000.

Taxonomic treatment of the genus

According to the above analysis, a key to the species was made.

Key to Coccocarpia species in South Korea

Isidia present, cylindrical to globose...C. palmicola (Maehwagiwajieu)

Isidia absent, biatorine apothecia usually present...C. erythroxyli (Giwajieu)

Taxonomy

1. (Spreng.) Arv. & D.J. Galloway, Bot. Notiser 132: 242 (1979). Fig. 2A, Fig. 3.

External Morphology

Thallus foliose, about 2~8 cm in diameter, color of the thallus include leaden grey, pale grey, bluish grey, and dark brown, darker when wet, color of the marginal parts usually lighter, sometimes even white (Fig. 2A). Thallus usually loosely attached to the substance. Lobes overlapping and epruinose, most of the lobes flabelliform, sometimes cuneate, very rare linear, 0.1~0.6 cm wide. The surface of the lobes canaliculated frequently, forming radiating lines, seldom flat. The margin of the lobes is deflexed. Sometimes lobe margins laciniate, apices of the lobes rounded. Second lobes often present. Lobules are rare on the marginal part of the lobes, and more frequently exist in the central parts, among the isidium (Fig. 3-5).

Fig. 2

Habitat of C. palmicola (HUR 040427) (A) and C. erythroxyli (HUR 030609) (B). Isidia (more dense and dark part) are present at the center of upper surface of C. palmicola. Black and biotrorin apothecia are clearly shown on the supper surface of C. erythroxyli.

Fig. 3

1. Globose isidia of C. palmicola 030437. 2. Cylindrical isidia of C. palmicola 030609. 3. Marginal lobules of C. erythroxyli 040005. 4. Apothecia of C. erythroxyli 040743. 5. Flabelliform lobules of C. palmicola 040255. 6. Rhizines forming concentric lines, C. palmicola 040006. 7. Vertical section of apothecia of C. erthroxyli 040743. 8. Fusiform spores of C. erythroxyli 040743. Scales: 1: 0.1 mm, 2: 0.5 mm, 3: 0.5 mm, 4: 1 mm, 5: 0.2 mm, 6: 1 mm, 7: 25 µm, 8: 12.5 µm.

Cortices present. Upper surface with very clear concentric ridges, sometimes glossy, pycnidia sometimes presents on the upper surface. Lower surface with thick hair-like rhizines, usually bluish dark, brown or white, sometimes formed concentric lines (Fig. 3-6), sometimes scattered and forming a dense hypothallus, rhizines often stretched beyond the margins.

Isidia present, with darker color than the thallus or concolorous with thallus, cylindrical and usually coralloid branched (Fig. 3-2), sometimes globose (Fig. 3-1). Soredia absent. Medulla present and the color are always white. Apothecia are nearly not seen.

Chemistry

Thallus K-, P-, C-. KC-; no lichen substance detected.

Habitat

On bark, usually bark of Quercus, sometimes on rock.

Distribution in Korea

Mt. Baekwoon, Mt. Dukyoo, Mt. Halla, Mt. Hugseok, Mt. Jiri, Mt. Jogae, Mt. Naehang, Mt. Wolak, Mt. Wulchul, Mt. Sobaek, Mt. Odae, Mt. Sorak (Fig. 4).

Fig. 4

Distribution of Coccocarpia species in South Korean. Circles (•) and squares (▪) represent the localities previously (Park, 1990) and newly reported in this study, respectively. The previous records confirmed by newly collected specimens in this survey were indicated as stars (⋆).

Remarks

This species could be characterized by its cylindrical to globose isidia. Rhzines in the lower surface usually are denser, shorter and thicker, rarely forming concentric lines, than the C. erythroxyli. Apothecia are not seen.

Representatives of the 33 Specimens examined

Mt. Jiri, N35°17'43.0" E127°33'00.7"alt. 1380 m, on Quercus bark, Jae-Seoun Hur 060238. Mt. Dukyoo, N35°51'27.5" E127°46'13.3"alt. 895 m, on Quercus bark, Jae-Seoun Hur 060450. Mt. Baekwoon, N35°37'08.4" E127°38'06.1", alt. 1165 m, on bark, Jae-Seoun Hur 060621. Mt. Jogae, N34°59'27.9" E127°20'01.8", alt. 201 m, on rock, Jae-Seoun Hur 040005. Mt. Sorak, N38°07'14.5" E128°23'03.5", alt. 1355 m, on bark + moss + soil, Jae-Seoun Hur 041489. Mt. Wolak, N36°51'37.6" E128°06'13.2", alt. 340 m, on rock, Jae-Seoun Hur 041174. Mt. Hugseok, N34°41'21.4" E126°40'51.4", alt. 203 m, on rock, Jae-Seoun Hur 050456. Mt. Naejang, N35°29'46.9" E126°53'40.7", alt. 700 m, on rock, Jae-Seoun Hur 030437.

2. (Spreng.) Swinscow & Krog, Norw. Jl Bot. 23: 254 (1976). Fig. 2B, Fig. 3.

Thallus foliose, 2~9 cm in diameter, color varies from brown to grey, usually lead-grey, sometimes pale, dark or bluish grey, colors darker when the thallus is wet (Fig. 2B). Thallus closely adnate, sometimes loosely attached to the substance. Lobes epruinose and usually weakly branched, secondary lobes often present. Lobes usually narrow cuneate, sometimes overlapping and flabelliform, with round apices, 0.1~0.8 cm wide. Surface of the lobes canaliculated, with or without radiating lines, sometimes flat and even shining. Margins of the lobes are always deflexed. Some of the lobe margins laciniate. Lobules often present, usually round and overlapping in the old parts of the thallus with scalelike shape, sometimes on the edge parts of the lobes (Fig. 3-3), less than 0.1 cm wide.

Cortices present. Upper surface with unclear concentric ridges. Lower surface with hair-like rhizines, color varies from bluish-black to bluish-white. Rhizines usually form concentric lines. Medulla always present and the colors are white. Isidia and soredia absent. Pycnidia present sometimes.

Apothecia (Fig. 3-7) mostly present, biatorine, usually black (Fig. 3-4), sometimes ball-shape and sometimes strongly convex or slightly rose over the surface. Usually with white hairs stretched from the bottom part of the apothecia. Spores fusiform, hyaline, thin-walled and simple, the length is usually about 10~14 × 3~5 µm (Fig. 3-8).

Thallus K-, P-, C-. KC-; no lichen substance detected.

On the rock surface or bark.

Mt. Baekwoon, Mt. Chentae, Mt. Dukyoo, Mt. Halla, Mt. Jiri, Mt. Jogae, Mt. Juwang. Mt. Sobaek, Mt. Sorak (Fig. 4).

The species is similar to C. palmicola, but without any isidia, having biatorine apothecia on the upper surface. Rhizines usually sparse, and forming concentric lines. Papilliform pycnidia sometimes present on the upper surface, usually smaller than the apothecia.

Representatives of the 18 Specimens examined

Mt. Jiri, 35°17'45.1" N, 127°33'38.5" E, alt. 1202 m, on Quercus bark, Jae-Seoun Hur 060772. Mt. Baekwoon, 35°04'17.4" N, 127°39'27.1" E, alt. 840 m, on rock, Jea-Seoun Hur 041267. Mt. Halla, 33.23'18.1N, 126.29'45.1E, alt. 1280m, on bark. Jae-Seoun Hur 040727. Mt. Sorak, N38°11'16.4'' E128°21'42.7'', alt. 450 m, on rock, Jae-Seoun Hur 041516.

The species not found in this time

Coccocarpia pellita (Ach.) Müll. Arg. was previously recorded in South Korea (Park, 1990; Hur et al., 2005). C. pellita is currently treated as Umbilicaria polyrrhiza (L.) Fr. (www.indexfungorum.org). According to her, this species was not common and most abundant on Mt. Jiri. The only difference between C. pellita and C. palmicola was the shape of isidia. C. pellita had flattened isidia, instead of cylindrical one. There was no chemical difference between two species. C. palmicola was also most abundant on Mt. Jiri in her collections which have been deposited in Duke University, USA. However, we have seen no corresponding specimens during our expeditions and, possibly, they are under threaten of extinction.