A phylogenetic classification of jumping spiders (Araneae: Salticidae)

The state of knowledge of Salticidae, after 250 years of taxonomic studies, is highly unsatisfactory. The World Spider Catalog lists now 5934 scientific names of Salticidae considered available, that is published in accordance with the International Code of Zoological Nomenclature. How many of them have biological meaning? According to Prószynski (2016b) out of these names only 2172 can be assigned to any recognizable biological species, that is having diagnostic drawings of genitalic characters for both sexes, additional 2204 species are incompletely known, having drawings for one sex only. Of the remaining names, there is a chance that some of 925 names may become revalidated by eventual taxonomic revisions, because their type specimens are preserved and located in known collections (Prószynski 1971, 2016b). 572 names have no types specimens located (that is presumably lost) and no diagnostic drawings, so they are in fact useless ballast on species records. Prószynski (op. cit.) quotes also 5092 junior synonymic names, many of them probably mismatched. The number of recognizable genera amounts to 573. The exact figures in this statistic keep changing with every new publication, but we understand that only fraction of really existing species has been ever described and there may be twice as much species in the nature pending discovery and description, a lot of which will be whipped out, together with their environments, before even collected.

Management of data pertaining to thousands of species require development of a system permitting storage, easy retrieval and exchange of information of all sorts. To be able to move among thousands of species, they should be arranged into uniform (more or less) groups of several hundreds species each, recognizable and distinctly different from other groups of the same rank. These smaller groups should be again subdivided into even smaller groups, named genera, containing up to several dozens of species. Groups, of each rank, should fulfill basic condition - be clearly defined, documented and thus recognizable. From the point of view of a person identifying spiders it is irrelevant how the diagnostic characters are selected and which philosophical comments are assigned to them, they must be easily noticeable, characterize all species.

In the taxonomic practice, species are always defined (sufficiently or insufficiently) by their description, although individual variation are often misinterpreted, mismatched sexes hamper further syntheses. Genera consist of species closely related - that is looking similar, and authors usually follow that principle, unfortunately have various ideas by which characters genera could be defined, not to mention authors´ experience as well as abilities to recognize and document species and genera. All that leads to delimiting heterogeneous genera, or to their excessive splitting.

International Code on Zoological Nomenclature contains various rules on handling genera, splitting them, or merging, all made on assumption that genera are coherent groups of related species. However, in Salticidae, many genera are still incoherent, incidental groups of species, and applying ICZN rules (for instance on transferring unknown species together with their incidental type species) without preliminary revision become senseless wastage of time. Speaking simply, genera (that is ALL assigned species) must be revised, before further rearranged.

Taxa of higher rank, above genus level, containing several hundreds of species, are even more difficult to delimit. They should fulfill criterion of affinity of included genera, which means finding out characters mutual to included genera, and at the same time sufficiently different from other groups of the same rank. At present, knowledge of Salticidae is too insufficient, to be sure of any grouping of species, created by various methods for different purposes (identification, establishing phylogenies, and various sundry purposes). Creating groups is stimulating, providing their provisional character is remembered. Classification of species of unknown faunae starts from supergeneric characters, but if these characters are derived from heterogeneous group, then their application may be limited to some members of the group only, which will derail the whole classification process. It is better to realize purposes of delimitation of particular groups, mixing up purely identificatory purposes with phylogeny influences negatively both directions of research. I propose therefore to create provisional system of pragmatic classification of genera, parallel to more theoretical system of affinities and phylogeny.

© MADDISON (2015): A phylogenetic classification of jumping spiders (Araneae: Salticidae). Journal of Arachnology 43(3): 231-292.

Genera not mentioned in MADDISON´s classification:
Ancepitilobus, Padillothorax, Paramaevia, Spadera, Urogelides,