A taxonometric investigation of the Alluroididae (Oligochaeta)
Journal of Zoology
155(1): 55-86
Publication
Annelidabase
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By computation of coefficients of similarity and construction of dendrograms by the highest single linkage, average linkage and complete linkage methods, the interrelationships of five members of the Alluroididae have been assessed together with their affinities with Syngenodrilus lamuensis Smith & Green (1919) and Drawida grandis (Bourne), 1894 (Monili-gastridae). The latter two species were included in the study because Syngenodrilus was placed in the Moniligastridae by its authors and was made the basis of an elaborate hypothesis of moniligastrid evolution by Stephenson (1930) while Gates (1945) argued cogently for its inclusion in the Alluroididae. To assist in “calibrating” phenon levels in terms of taxonomic ranks, species from other families were included in the taxonometric comparisons, namely Pygmaeodrilus affinis and Eukerria saltensis (Ocnerodrilidae), Digaster armifera (Megascolecidae) and an unnamed species of the Tubificidae. The three linkage methods reveal the same interrelationships within the five alluroidids and justify the following taxonomic changes*. Alluroides tanganyikae s. Brinkhurst (1964), from Mt Elgon, is removed from A. tanganyikae Beddard (1906) and made the nominal subspecies of a new species, A. brinkhursti; new material, from Ethiopia, is placed in this species as the new subspecies A. brinkhursti abyssinicus; Alluroides americanus Brinkhurst (1964), from Argentina, is made the type of a new monotypic genus Brinkhurstia; a new species from the Transvaal is placed in a new monotypic genus, as Standeria transvaalensis; Alluroides, Brinkhurstia and Standeria are placed in the subfamily Alluroidinae, while the Syngenodrilinae, which show in all dendrograms a very low phenetic affinity with the Moniligastridae, are transferred to the Alluroididae. Descriptions drawn from the author's examination of type material are given for all the new taxa together with an emended description of A. pordagei Beddard (1894), the type species of the genus, and a synopsis of descriptions of Syngenodrilus lamuensis. A key to species of the Alluroidinae is given in conjunction with a discussion of the comparative morphology of all species of the subfamily. The highest linkage dendrogram, and less certainly, the average and complete linkage dendrograms suggest that the Ocnerodrilidae and Megascolecidae s. Gates (1959) are only distinct at the subfamily level and the author reiterates earlier doubts (Lee, 1959; Jamieson, 1963) that the Octochaetidae and Acanthodrilidae, which are distinguished from each other by their nephridia (Gates, 1959), are valid groups or that they should be excluded from the Megascolecidae s. lat