Development inCladonia Ochrochlora

Phenotypical plasticity and homoplasy complicate species delimitation in the Cladonia gracilis group (Cladoniaceae, Ascomycota)

“…The morphological differences used to distinguish the two species are as follows: 1) the podetium basal cortex is longer and thicker in C. ochrochlora; 2) the presence of discrete soralia between cortex patches in C. ochrochlora, while C. coniocraea has diffuse soralia; 3) soredia are larger in C. ochrochlora than in C. coniocraea; 4) presence of broad cups in C. ochrochlora, while these are rare in C. coniocraea, and narrow when present. Further, in C. coniocraea the primary thallus squamules show deep incisions, while in C. ochrochlora the squamules are in general undivided (Hammer 1991(Hammer , 1993(Hammer , 1995Ahti 2000;Ahti and Hammer 2002). However, the PCA analysis does not show different groups among the specimens of C. coniocraea and C. ochrochlora.…”

Thallus Organization and Development in the Fruticose Lichen Aspicilia Californica, with Comparisons to other Taxa

“…According to the interpretation supported most recently by the work of Jahns (1970) and adopted by Ahti (1982), the podetium of Cladonia is homologous with an apothecial stalk, and thus fundamentally ascocarpic in nature. Hammer (1993) rejected this view, citing the anachronistic appearance of ascogonia on top of already formed podetia in some species, and challenging assertions of sexual function in the podetium.…”

New Species and Combinations in The Lichen Flora of Great Britain and Ireland

“…The definition of the term ' generative tissue ' has recently been discussed (Hammer 1993;Jahns et al 1995). In the present paper it is used in the sense of Jahns (1970).…”

“…summarized in Henssen & Jahns 1973;Henssen et al 1981;Letrouit-Galinou & Bellemere 1989) helped to circumscribe natural entities, and the ontogeny played a major role in the classification proposed by Henssen & Jahns (1973), ontogenetic studies are mainly undertaken by these schools and this character set is rarely used by other authors. Furthermore, the use of ontogenetic characters in systematics was recently criticized (Hammer 1993; but see Jahns et al 1995) or its limited use in some cases emphasized (Letrouit-Galinou & Bellemere 1989).…”