[ref. ID; 6974 (Nemec et al., 1987)]
The historical derivation of the subfamilial classification of the Naididae was discussed by Sperber (1948), who recognized four subfamilies. Two of these subfamilies are monotypic Pristininae: Pristina; Paranaidinae: Paranais, the Chaetogastrinae contains two genera (Chaetogaster, Amphichaeta), and the fourth, the Naidinae, contains all other genera. This classification was uncritically accepted by Brinkhurst (Brinkhurst and Jamieson 1971) but because Sperber's work was completed without access to much worldwide literature predating 1939, and our general knowledge of the taxonomy of aquatic oligochaetes has greatly expanded in the last three decades, it is forth objectively examining the basis for the subfamilial classification of the Naidiae.
A data matrix of 23 generic or subgeneric taxa versus 24 characters and a shorter matrix of 15 characters were analyzed by means of ordination, cluster analyses, parsimony, and compatibility methods (the last two of which are phylogenetic tree reconstruction methods) and the resultes were compared inter alia and with traditional methods.
Taxonomic implications
The clearest overall impression derived from thse analyses is that there are two major groups (subfamilies) within the Naidiae, one of which can be further subdivided. This leads us to the conclusion that we might profitably employ the term tribe for the minor subdivisions of one of the two subfamilies, as summarized below. We have made no attempt to use the results of our analyses to infer the detailed generic relationships beyond the tribe level. We are simply trying to identify monophylies that can be used to investigate the higher order relationships in the future.
Family Naididae
Type Genus: Nais Muller
Subfamily Naidinae Lastockin 1924 emended
Type Genus: Nais Muller
Synapomorphies: Atria without prostates, vascular system complex.
Tribe Naidini trib. nov.
Type Genus: Nais Muller
Included genera: Uncinais Levinsen, Ophidonais Gervais, Specaria Sperber.
Incertae sedis: Neonais Sokolskaya.
Synapomorphy: Prostates on the vas deferens.
Tribe Derini trib. nov.
Type Genus: Dero Oken
Included genera: Branchiodrilus Michaelsen, Haemonais Bretscher, Allonais Sperber.
Incetae sedis: Rhopalonais Dzwillo and Grimm.
Synapomorphies: Stomach absent, vasa deferentia enter the atria apically.
Tribe Pristinini trib. nov.
Type Genus: Pristina Ehr. em. Br.
Included genus: Pristinella Brinkhurst.
Incertae sedis: Bratislavia Kosel.
Synapomorphies: (? Defined by plesiomorphy, dorsal setae begin in II)
Tribe Chaetogastrini trib. nov.
Type Genus: Chaetogaster von Baer.
Included genera: Amphichaeta Tauber, Paranais Czerniavsky, Homochaeta Bretscher.
Synapomorphy: Hair setae absent.
Subfamily Stylarinae subfam. nov.
Type Genus: Stylaria L.
Included genera: Arcteonais Piguet, Ripistes Dujardin, Vejdovskyella Michaelsen, Slavina Vejdovsky (partim).
Incertae sedis: Stephensoniana Cernosvitov, Piguetella Sperber.
Synapomorphies: No nodules on needles, prostomium with a proboscis (most genera) (symplesiomorphy: atria with prostate cells).
Two Slavina species (S. isochaeta Cernosvitov, S. evelinae (Marcus)) are treated as a separate taxon, but are not necessarily related. The analytical results support the contention (Sperber 1948) that these species are unrelated to the type species of Slavina.
Some parallelisms exist in the synapomorphies used to define these taxa. Uncinais and Ophidonais (Naidini) lack hair setae, Pristina may have prostates on the vasa deferentia, but the atria are tubular and the distinction between arium and vas may be obscured; further study of this feature is called for. Bratislavia lacks a stomach, as in the Derini, and the apical position of the vas on the atrium is assumed for Dero, and is probably plesiomorphic in Allonais but apomorphic in three genera outside the Derini. The needles lack nodulae in Branchiodrilus, and dorsal setae begin in II in Homochaeta and Stephensoniana, parallelisms with the Stylarinae and Pristinini, respectively.