On the identity of Aporcelinus granuliferus (Cobb, 1893) Andrássy, 2009 and its taxonomic consequences

Abstract

The intricate taxonomical history of Aporcelinus granuliferus, the most often recorded species of its genus, is reviewed and discussed. A new concept, based on its original description, is proposed for it as type material is apparently lost although available data provide enough information to complete and update its diagnosis: 1.20-1.70 mm long body, lip region 15-16 μm broad, odontostyle 17-21 μm long, neck 309-403 μm long, pharyngeal expansion 155-214 μm long, dorsal cell mass present at pharyngo-intestinal junction, uterus simple and up to one body diam. long, V = 47-55, female tail conical with acute tip and occasionally somewhat recurved dorsad (46-55 μm; c = 24-37; c′ = 1.4-1.9), and male absent. The population studied by Thorne & Swanger (1936) is certainly not conspecific with Cobb’s original one due to significant differences in lip region breadth and odontostyle length, and belongs to a non-described species, herein characterised and named as A. brasiliensis sp. n.: 1.5-1.6 mm long body, lip region offset by constriction and 24-27 μm wide, odontostyle 25-28 μm long, neck 345-370 μm long, V = 48, tail conical (46-55 μm; c = 29-32; c′ = 1.3-1.4) with very finely rounded or acute tip and barely recurved dorsad, spicules 54-72 μm long and nine irregularly spaced ventromedian supplements with no hiatus. The three females deposited with USDANC are not identical either to those studied by Cobb or by Thorne & Swanger, and also belong to a non-described species, herein characterised as named as A. neogranuliferus sp. n.: 1.25-1.31 mm long body, lip region offset by constriction and 17.5-18.0 μm broad, odontostyle 18 μm at its ventral side, neck 312-337 μm long, pharyngeal expansion 136-168 μm long, dorsal cell mass present at level of pharyngo-intestinal junction, uterus simple and 41-48 μm long or 0.6 times corresponding body diam., V = 49-53, female tail conical (28-35 μm; c = 36-46; c′ = 0.8-1.0) with finely rounded terminus and no hyaline region. Both Dorylaimus reynecki and D. yucatanensis, hitherto considered to be identical to A. granuliferus, are valid species, being transferred to Aporcelinus as A. reynecki comb. n. and A. yucatanensis comb. n. The available information on D. micrurus and D. menzeli lacks sufficient relevant detail to characterise these species, which are therefore regarded as species inquirendae within Aporcelinus and are transferred as A. micrurus comb. n. and A. menzeli comb. n. The true identity of other records of A. granuliferus is analysed and discussed in the light of the new concept of the taxon.