摘要:

Phylogenetic relationships among genera of African colubrids were evaluated using estimates of divergence among serum albumins compared by microcomplement fixation. Representatives of about half of the extant genera of African colubrids, as well as the Elapidae,Atractaspisand the Madagascan colubridLeioheterodon,were analysed. The tree of best fit to the data has an unresolved basal polychotomy comprising at least five lineages of colubrids, as well as Elapidae andAtractaspis; thus, colubrids were not demonstrably monophyletic with these data. Two cosmopolitan clades, colubrines and natricines, are represented in Africa by series of closely related genera, but divergence among other genera is relatively great. Rate tests show that this is apparently not due to higher rates of albumin evolution in these, relative to other colubrids. Among the other associations supported by the immunological data are: (1)Psammophis‐(Rhamphiophis‐Dipsina)‐Malpolon‐Psammophylax; (2)Amblyodipsas‐Macrelaps; (3) (Lycodonomorphus‐Lamprophis)‐Mehelya; and (4) Colubrinae‐Natricinae.Grayiais questionably associated with the colubrine‐natricine lineage.ProsymnaandLycodonare clearly members of the colubrine clade, andAmplorhinuspossibly associates withLeioheterodon. Gonionotophis, Duherria, LycophidionandPseudaspisshow no strong association with any other genera, and represent other basal or near‐basal clades within the colubrid/elapid radiation. The immunological data do not support a clade comprising the Elapidae,Atractaspisand some ‘aparallactines’ relative to Viperidae and other colubrids. The basal colubrid‐elapid‐Atractaspisdivergence occurred more than 30 Myr ago, and the fossil record of colubrids in Africa greatly underestimates both the age and clade diversity of this group. In contrast to the pattern of radiation in the neotropics, where most colubrids belong to one of three major clades, in Africa only the colubrine lineage comprises a substantial portion of the extant generic diversity; most other genera stem from relatively ancient cladogenetic events and have

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1994.tb01473.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Morphology and schmelzmuster of rootless cheek teeth of 25 extant rodent genera were studied in relation to jaw movement. A differentiation between leading and trailing edges is observed regularly in enamel thickness and schmelzmuster. Similarities between antagonists are interpreted as ‘functional symmetries’. Differences in the enamel thickness, the schmelzmuster and orientation of cutting edges are controlled by functional and phylogenetic constraints. The heterogenous sample allows discrimination between these two constraints. The most obvious functional constraint leads to the almost regular occurrence of radial enamel on the push sides of cutting edges. The degree of functional symmetry seems to be determined by phylogenetic limitati

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1994.tb01474.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

The weevilRhinocyllu conicusdevelops only in the flowerheads of thistles {Asteracea; Carduineae) and therefore it is used as a biocontrol agent against thistle weed species. Populations out of 14 regions within its natural distribution area (from the Atlantic coast in the west to Israel in the east) were analysed by means of allozymes and morphometries. In both analyses the 14 populations were grouped into two concordant units. Based on nine scored loci (six of them polymorphic), mean Nei's genetic distance between the two groups was 0.073. In a reclassification test following DFA of morphometric data, 93.2% of all individuals were grouped back into the correct group. The two groups were considered to belong to a temperate and a Mediterranean subspecies respectively, the latter probably identical to the formerly describedRhinocyllus oblongus.

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1994.tb01475.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Brachionus africanus sp. nov.andItura symmetrica sp. nov.are described from Kenya. The Ituridae are revised, a key to the species is provided and a cladistic analysis performed. Some remarks on rotifer endemism in Africa are given.

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1994.tb01476.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY