Verrucaria Schrad.

Lichens Pan-Z (2007) - Flora of New Zealand Lichens - Revised Second Edition Pan-Z

VERRUCARIA Schrad., 1794, nom. cons.

Type : Verrucaria rupestris Schrad.

Descriptions : Flora (1985: 604). See also McCarthy (2001j: 176).

Key

Not parasitic on other lichens

Parasitic on species of Lecidea

* cramba

Thallus growing on aquatic or seashore rocks

Thallus not growing on aquatic or seashore rocks

Thallus growing on aquatic (freshwater) rocks

Thallus growing on seashore rocks

Ascospores 6–15 μm long

Ascospores (12–)15–25(–35) μm long

Ascospores broadly ellipsoidal to subglobose, 6–11 × 4.5–7 μm; thallus 20–50 μm thick, gelatinous when moist, dark-green to blackish, not black-punctate; perithecia prominent, 0.13- 0.26 mm diam.

aquatilis

Ascospores elongate-ellipsoidal, 8.5–15 × 4.5–7 μm; thallus 60–120 μm thick, somewhat gelatinous when moist, grey-brown to greenish black, often black-punctate; perithecia usually immersed, 0.16–0.26 mm diam.

rheitrophila

Thallus pale pink-grey to pale grey-green

Thallus medium to dark grey-green or almost black

Involucrellum contiguous with hyaline exciple; ascospores 15–24 × 6.5–9.5 μm; perithecia 0.18–0.3 mm diam., immersed; thallus rimose to areolate, usually with a brown-black basal layer

praetermissa

Involucrellum lacking; exciple brown-black; ascospores 19–30 × 6–12.5 μm; perithecia 0.23–0.32 mm diam., immersed; thallus ±continuous, without a black basal layer

fiordlandica

Perithecia (0.16–)0.24(–0.4) mm diam.

Perithecia (0.2–)0.4(–0.64) mm diam.

Ascospores 12–24 × 5–10.5 μm

Ascospores 18–35 × 8–14 μm; perithecia 0.18–0.3 mm diam., ±immersed; thallus mid-brown, mostly continuous, with a black basal layer; photobiont 5–10 × 3–6 μm

austroschisticola

Involucrellum 40–50 μm thick; perithecia 0.16–0.27 mm diam.; thallus lacking a black basal layer; photobiont 7–20 × 7–16 μm

phaeoderma

Involucrellum 60–120 μm thick; perithecia 0.18–0.35(–0.4) mm diam.; thallus usually with a black basal layer; photobiont 4–11 × 4–8 μm

inconstans

Ascospores 12–27 μm long

Ascospores 19–34 × 9.5–18.5 μm; perithecia (0.25–)0.4(–0.65) mm diam., usually prominent; involucrellum black usually contiguous with exciple, sometimes with a thin thalline covering; thallus grey-green to greenish black, continuous

margacea

Ascospores mostly ellipsoidal, 6.5–19(–12) μm wide; perithecia (0.2–)0.35(–0.5) mm diam., usually prominent; involucrellum black, spreading, sometimes with a thin, thalline covering; thallus grey-green to dark-green, continuous to rimose

hydrela

Ascospores mostly subglobose, (9–)12(–15) μm wide; perithecia 0.22–0.44(–0.5) mm diam.; thallus dark greenish brown to green-black, continuous

amnica

Thallus epilithic and conspicuous grey-brown to greenish brown, medium-green, olive-green, green-black or black

Thallus whitish to pale-grey, often poorly developed; perithecia semi-immersed to superficial, solitary to 2–3-together, 0.4–0.8 mm diam.; involucrellum thick and well-developed

prominula

Thallus not submerged

Thallus submerged, jet-black; involucrellum well-developed; ascospores broadly ellipsoidal, 15–17.5 × 8–9.5 μm

serpuloides

Thallus with prominent, glossy, branched and swollen ridges (jugae)

Thallus without prominent black ridges (jugae)

Thallus brownish

striatula ssp. australis

Thallus grass-green to dark-green

striatula

Thallus continuous to sparingly rimose; lower to mid-littoral species

Thallus strongly rimose to areolate; upper littoral to supralittoral species

Ascospores 7–13 μm long

Ascospores 10–16(–18) μm long

microsporoides

Perithecia immersed, to 0.15 mm diam.; exciple colourless

mucosa

Perithecia superficial, 0.2–0.34 mm diam., exciple medium-grey to brown-black

halizoa

Thallus foliose, margins placodioid

durietzii

Thallus crustose, margins not placodioid

Ascospores 8–15 × 4–7 μm

Ascospores 12–26 × 6–15 μm

Thallus black, effuse or in blotches

Thallus grey-brown to olive-green or greenish black, not effuse or in blotches

Perithecia sessile, to 0.25 mm diam.

adguttata

Perithecia immersed, 0.1–0.16 mm diam.

ceuthocarpa

Thallus grey-brown to mid-greenish brown; perithecia 0.22–0.45 mm diam

aucklandica

Thallus dark olive-green to green-black; perithecia 0.12–0.22 mm diam.

subdiscreta

Thallus pale-buff to grey-brown

Thallus olive-brown, greenish grey, dark grey-brown to dark greenish black

Thallus pale-buff with conspicuous black cracks; perithecia 0.1–0.2 mm diam., not radially ridged; exciple colourless; ascospores 10–15 × 6–9 μm

tessellatula

Thallus buff-brown, grey-brown or green-grey, without prominent black cracks; perithecia 0.2–0.3 mm diam., often radially ridged; exciple brown to brown-black; ascospores 14.5–23.5 × 7–11 μm

bubalina

Ascospores 9–16(–17) μm long

Ascospores 16–26 μm long; thallus olive-brownish, greenish grey to dark-brown; prothallus distinct; exciple brown-black

fusconigrescens

Thallus effuse, dull medium-green to greenish black, areolate only around perithecia; exciple brown-black, 25–32 μm thick; ascospores 9–12(–16) × 6–7(–8.2) μm

sessilis

Thallus strongly rimose to areolate, dark grey-green to greenish black; exciple 10–20 μm thick, hyaline to brown-black; ascospores 12–20(–22) × 6–8(–9) μm

maura

Thallus endolithic, inconspicuous, continuous, whitish or pale-grey

Thallus epilithic, conspicuous, rimose-areolate, grey, greenish, brown or blackish

Involucrellum present

Involucrellum absent

calciseda

Perithecia ⅓–½ immersed; ascospores 12–23 × 6–10 μm

dufourii

Perithecia ¾ immersed to sessile; ascospores 17–27 × 8–14 μm

muralis

Ascospores 17–37 μm long

Ascospores 8–18(–20) μm long

Thallus olive-green to greenish black; ascospores 17–30 × 8–14 μm

nigrescens

Thallus pale-brown to olive-green; ascospores 25–37 × 10–20 μm

macrostoma

Perithecia immersed; on limestone

Perithecia semi-immersed to superficial; thallus diffuse, dark-green to olive-brown; on greywacke and calcareous sandstone; ascospores 11–17 × 4–7 μm

dolosa

Perithecia 1–3 per areole; ascospores subglobose to globose, 8–13 × 8–11 μm

compacta

Perithecia 1 per areole; ascospores narrowly to broadly ellipsoidal, 10–18(–23) × 5–8 μm

glaucina

Verrucaria is a genus of crustose pyrenocarpous lichens having a green, unicellular photobiont; discrete, scattered, immersed to superficial perithecia with a variously developed involucrellum, and clavate to cylindroclavate, fissitunicate asci containing eight colourless, simple ascospores. It is included in the family Verrucariaceae (McCarthy 2001j; Eriksson et al. 2004; Pennycook & Galloway 2004; Eriksson 2005) and c. 320 species are known worldwide (Kirk et al. 2001). The paraphyses gelatinise long before maturity though periphyses persist. The genus has no demonstrable chemistry. Most species grow in warm-temperate to alpine-subpolar climates, with all but a few being saxicolous; on calcareous and siliceous rocks, mortar, concrete, compacted sand or soil, including periodically inundated maritime and freshwater species.

Systematic studies in the Southern Hemisphere and Asia were few or non-existent until relatively recently when the work of McCarthy on Australasian taxa, where 34 species are currently known (McCarthy 1991a, 1991b, 1991c, 1991d, 1991e, 1995c, 2001j; McCarthy & Johnson 1995, McCarthy & Kantvilas 2000a; 1998), reawakened interest in the genus. Japanese taxa are discussed by Harada in a series of papers containing much useful information on the genus (Harada 1992b, 1994, 1995a, 1995b, 1996, 2000). Corticolous species are discussed by Breuss (1993b, 1994b, 1994c, 1998c), and lichenicolous taxa by Zehetleitner (1978), Breuss (1998c) and Hoffman & Hafellner (2000).

In the Flora account (Galloway 1985a) 10 species of Verrucaria were recorded from New Zealand. Since then, many aquatic species were collected by Peter Johnson who sent material to Pat McCarthy for identification. After preliminary studies of a range of New Zealand material, McCarthy (1991e: 283) wrote: "In view of the abundance of preferred habitats in New Zealand and a climatic range that would be appear to be ideal for the genus, the total number of taxa may reasonably be expected to approach 70–80." The present treatment discusses 36 taxa, emphasising the fact that undoubtedly many more taxa, from a variety of substrata, are yet to be discovered here. In identifying species of Verrucaria, Hawksworth et al. (1992: 630) point out that it is important to pay attention to the texture of the thallus, immersion of the perithecia, whether any pits are formed in the rock substratum, the nature of any involucrellum and, especially, the size of the ascospores.

Verrucaria Schrad.

Key

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