Endemic distribution

Figure 22.3 Percentage (vertical scale) of endemic and cosmopolitan athyridid genera during Phanero-zoic endemics, distributed in one area genera of limited distribution (in 2-3 listed areas) genera of wide distribution (in 4-9 listed areas) cosmopolitan genera (present in more than 9 areas). Areas I, North Europe (Britain, Baltic, Norway) 2, Central Europe (Bohemia, Germany, Poland) 3, South Europe (France, Italy, Spain) 4, North Africa (Morocco, Mauritania) 5, Iran 6, Urals 7, Siberia 8, Kazakhstan 9, Central Asia 10, North China II, South China 12, Greenland 13, North America 14, South America 15, Australia, New Zealand. Abbreviations of unit names as in Fig. 22.1.

Are certain morphologies or morphological traits related to cosmopolitan or endemic distributions ... 

A detailed study of the flavonoid chemistry of the island endemics, the closely related G. tinctoria, and live additional species from the mainland provided additional evidence pointing toward G. tinctoria as the ancestral species (Pacheco et al., 1993). The flavonoid profiles of all species consisted of flavonol glycosides as major components with an unidentified flavone glycoside and several unidentified phenolic compounds (presumably not flavonoids). The pattern of distribution of the flavonol glycosides and unidentified flavones within the set of nine species proved to be extremely informative. (The phenols were ubiquitous and are not considered further.) Kaempferol glycosides were seen in neither the island species nor G. tinctoria, but were present, in several combinations, in the rest of the mainland taxa. The isorhamnetin glycosides showed the reverse pattern, with one exception the island endemics and G. tinctoria exhibited these compounds, whereas four of the other mainland species did not. The sole exception is G. boliviari, which exhibited one of the isorhamnetin derivatives. 

Phyletic links of apparent endemic species of the central Ebro valley with easternmost species were revealed after studying the insect communities at the Monegros region. These have a pre-Pleistocene origin of their relict distributions, associated with the persistence of steppe habitats over gypsiferous soils in the area since the Late Tertiary. Distributions of phytophages and their parasitoids on plants such as Krascheninnikovia ceratoides or Juniperus thurifera supported the continuity of their presence in the central Ebro valley through the Quaternary [14]. 

The Ebro catchment has the highest richness of autochthonous limnetic species in the Iberian Peninsula [51]. Salaria (blennius) fluviatilis, is common at the main channel and tributaries, and Chondrostoma toxostoma only occurs at the tributaries. Leuciscus cephalus is a fish of narrow distribution, found only at the Ebro river basin and other small catchments of NE Spain. Salmonids are common at the headwaters one species is native Salmo trutta and two introduced others, Salmo gairdneri and Salvelinus fontinalis. Part of the autocthonous species are endemic, for example the cyprinids Barbus graellsii and Barbus haasi, the cobitid C. calderoni with scattered and scarce populations [52] and A. iberus. 

Chemical elements Distribution of sub-regions and biogeochemical provinces Content of elements in biogeochemical food webs Biological reactions of organisms and endemic diseases... 

The distribution of both endemic diseases has been found to relate to selenium content in the soils. The two diseases are distributed mainly in a distinct wide belt, usually referred to as the disease belt, running from the northeast to southeast of China and located in the middle transition belt from the southern coast to the northwest inland region (Figures 3 and 4). 

In B.C. they are usually separated distributionally, but intermediate forms occur in intermediate localities. In Japan they may be temporally separated.The allocation of Gymnodinium breve to Ptychodiscus depends on the presence of a pellicle. Although not seen with TEM it can be seen with light microscopy. Geographic distribution is closely linked to taxonomy for, although some toxin producers appear to be endemic in a restricted sense, closely similar forms occur elsewhere (e.g.p, brevis) or the same species may be known by different names in different regions ( Gyrodinium aureolum ). 

DISTRIBUTION Endemic to the Mazatec zone of the Sierra Madre Oriental of the Mexican state of Oaxaca. 

Ostreopsis sp. have been suspected to be a source of palytoxin in cases of clupeotoxism (Yasumoto 1998 Onuma et al. 1999), and the Southwest Indian Ocean is a known clupeotoxism endemic zone (Hansen et al. 2001). It is therefore highly possible that O. mascarenensis, which is largely distributed in the western Indian Ocean, is involved in regional clupeotoxism incidents. 

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