The distribution of species is expressed by their occurrence in local faunal lists often compiled by non-taxonomists. In the case of rare or cryptic species, this can pose a severe limitation on the validity and thus the application of the resulting biodiversity data. Here, we show an example of a shallow-water echinoid to illustrate problematic distribution data based on misidentification. This species, Arbaciella elegans, was established on the basis of Central African material and later reported from various places in the Mediterranean and the Northern Atlantic. Morphological comparison with the type material casts considerable doubt on the validity of these records. Genetical characterization of material from the Azores clearly shows that the dark Arbaciella phenotype reported to the Mediterranean and north-east Atlantic in fact represents juveniles of another species, namely Arbacia lixula. |
