Vulcanochloris symbiotica Vančurová, Peksa, Němcová et Škaloud, 2015

Vančurová, Lucie, Peksa, Ondřej, Němcová, Yvonne & Škaloud, Pavel, 2015, Vulcanochloris (Trebouxiales, Trebouxiophyceae), a new genus of lichen photobiont from La Palma, Canary Islands, Spain, Phytotaxa 219 (2), pp. 118-132 : 125

Vulcanochloris symbiotica Vančurová, Peksa, Němcová et Škaloud , sp. nov.

Vegetative cells usually spherical, occasionally oval and oviform, up to 18 μm in diameter ( Figs. 4J, K, N ). Cell wall thin, seldom a flat local thickening of the cell wall (up to 3 μm thick) can be distinguished ( Fig. 4J ). Very rarely, the cell wall is slightly thickened along its entire surface. Chloroplast in young cells assumes the central position with several lobes spreading towards the cell’s periphery ( Fig. 4J ). Mature cells exhibit a broad range of chloroplast types, with a deeply lobed form being the mostly frequently observed ( Figs. 4K–M ). In addition, the shallowly lobed ( Figs. 4N, O ), crenulate ( Figs. 4P, Q ) and echinate chloroplast ( Fig. 4R ) is observed as well. Lobes of the deeply lobed chloroplast are not simply terminated, but extended to either irregular plates ( Fig. 4L ) or branched projections ( Fig. 4M ). The chloroplast contains one distinct pyrenoid located in its centre ( Figs. 4K, N, P ). The pyrenoid occasionally contains one to several spherical incisions ( Fig. 4N ). A number of small starch grains are distributed around the pyrenoid ( Fig. 4K ). Asexual reproduction by 32 aplanospores or 128 zoospores produced in spherical or ellipsoidal sporangia with diameters up to 22 μm ( Figs. 4S, T ). Zoospores drop-shaped, naked, with two apical flagella and a simple basal chloroplast, 7.0–7.5 μm long and 3–4 μm wide ( Fig. 4U ).

Type:— SPAIN. Santa Cruz de Tenerife: La Palma, top of Volcán de San Antonio, 28.485500º N, 17.849917º W, 589 m a.s.l., L. Vančurová & J. Malíček, 17 May 2013 (holotype: CAUP!, cryopreserved photobiont cells isolated from the specimen A 72, deposited in the Culture Collection of Algae of the Charles University in Prague as the item TYPE-H 1017). Reference strain: CAUP H 1017

Habitat:—In thalli of Stereocaulon vesuvianum growing on basalt lava stones and rocks. Etymology:—The specific epitheton reflects symbiotic lifestyle of this alga.

Figures

FIGURE 4. Vulcanochloris, gen. nov. Morphology in a light or a confocal microscope. A–I. Vulcanochloris canariensis, sp. nov. A– C. Spherical or oval vegetative cells. B–E. Crenulate chloroplast. F−G. Shallowly lobed chloroplast. A−C, H. One distinct, centrally positioned pyrenoid, frequently containing one to several spherical incisions. I. Asexual reproduction by 16–64 aplanospores formed in spherical or ellipsoidal sporangia. J−U. Vulcanochloris symbiotica sp. nov. J, K, N. Spherical, oval and oviform vegetative cells. K−M. Deeply lobed chloroplast. N, O. Shallowly lobed chloroplast. P, Q. Crenulate chloroplast. R. Echinate chloroplast. K, N, P. One distinct pyrenoid located in its centre. N. One to several spherical incisions in pyrenoid. S, T. Asexual reproduction by 32 aplanospores or 128 zoospores produced in spherical or ellipsoidal sporangia. U. Zoospores drop-shaped, naked, with two apical flagella and a simple basal chloroplast. V−DD. Vulcanochloris guanchorum, sp. nov. V, W. Spherical, occasionally oval vegetative cells. V. Chloroplast in young cells in the central position with several lobes spreading towards the cells periphery. W−Y. Deeply lobed chloroplast. Z−AA. Shallowly lobed chloroplast. BB. One distinct, centrally positioned pyrenoid, often containing one to several spherical incisions. CC, DD. Asexual reproduction by 16−32 aplanospores or 64−128 zoospores produced in spherical or ellipsoidal sporangia. Scale bars = 5 μm.