Family delimitation

Buck, W. R. (1988) Another view of familial delimitation in the Hookeriales. Journal of the Hattori Botanical Laboratory, 64 29-36. 

Order An arbitrarily delimited grade or category of biological classification intermediate between classes and families, and composed of related families. 

Problems with generic delimitation and evolutionary trends in the family Brassicaceae are complex (Al-Shehbaz, 1973). Glucosinolates, however, often exhibit species-specific arrays of compounds that are of value for the study of systematics and evolutionary studies in this group (Chew, 1988). 

Cottrell, M. and Kock, J.L.F. (1989) The yeast family Lipomycetaceae and the genus Myxozyma 1. A historical account of its delimitation and 2. The taxonomic relevance of cellular long-chain fatty acid composition and other phenotypic characters. Syst. Appl Microbiol. 12, 291-305. 

Still hampers — the delimitation of separate groups of species within Ihe family and the determination of their mutual evolutionary relationships. That is actually what can be seen there was no consensus among bryologists on the classification of the Hypopterygiaceae up to about 1990 (e.g.. Table 4.2). 

Circumscriptions of the Meteoriaceae in Some Classifications of Mosses and New Delimitations for the Family Based on Phylogenetic Analyses... 

Monkemeyer, W. (1927) Die Laubmoose Europas. IV. Band, Erganzungsband. Andreaeales-Bryales. Leipzig. Nishimura, N., Higuchi, M., Seki, T. and Ando, H. (1984) Delimitation and subdivision of the moss family Hypnaceae. Journal of the Hattori Botanical Laboratory, 27 20-46. 

Preperistome plates adhere to the outer face of the exostome and are formed by deposition in the cell layer external to the OPT. These plates were previously used to delimit Mesonodon (Buck, 1980 Gradstein et al., 2001). However, these structures have been found to occur sporadically in a range of species in both Entodon and Erythrodontium and to be lacking in many specimens of Mesonodon (Figure 12.2D). They appear to be an occasional by-product of peristome reduction and of no taxonomic significance in this family. 

The all-inclusive character stroma can be employed for the definition of genera, subgeneric taxa, and sometimes only species, as, for example, in Pertusaria, where stromata are found in only some of the species and then usually just weakly delimited. It is remarkable that reproductive stromata are predominantly of tropical origin. The tendency to develop stromata may serve as a family-specific character in theTrypetheliaceae and Laureraceae. 

The families grouped under the Arthoniales below in our proposed classification also seem to represent an evolutionary line wholly dominated by lichenized fungi with a number of species occurring as parasites on lichens. The boundary with nonlichenized forms is of course harder to draw (0/ egm/ /z 3[-Hysteriales ) and satisfactory delimitations will require much more study. One should consult the discussions of the Arthoniaceae by Muller and von Arx (1962, p. 223). 

Genera Byssocaulon Mont. (6), Chrysothrix Mont. (1), Temnospora Mass. ( 1) consisting of very densely branched, thick-walled, anastomosing hyphae. The delimitation of this family is unsettled. 

The family is still not homogeneous even with this delimitation. 

Other groups long assigned to the Lecideaceae might belong to this recently narrowly delimited family. 

These more complex phenylalanine-derived alkaloids, benzylisoquinolines and others, are also found in ca. 40 families the exact number depends on how the various families are delimited. In about 12 of them the occurrence of the alkaloids is rare. The main distribution in the subclass Magnoliidae, Dictoyledons (Dahlgren 1980), is as follows ... 

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