Dictynidae

Grbić, Gordana, Hänggi, Ambros & Krnjajić, Slobodan, 2021, Spiders (Araneae) Of Subotica Sandland (Serbia): Additional Arguments In Environmental Protection, Acta Zoologica Academiae Scientiarum Hungaricae 67 (1), pp. 15-61 : 23

Family Dictynidae

Argenna patula (Simon, 1874)

Material: 13.06.2014 F 3mm; 13.06.2014 W5 2 mm; 27.06.2014 F 3mm.

Determination: LOCKET & MILLIDGE 1951, WIEHLE 1953, ROBERTS 1985.

Global distribution: Palaearctic.

Habitat: Under detritus ( NENTWIG et al. 2020). Under stones, often in dry habitats with scarce vegetation ( ROBERTS 1985). Saline wetlands (halotolerant) ( FINCH 2008).

Note: There are some problems for distinguishing the species from Argenna subnigra ( O. pickard Cambridge, 1861 ) and, controlling museum collections, one will regularly find miss-matched determinations in the older times. In the males the form of the palpal tibia is a quite good character: short, rather square in subnigra and longer in patula ( WIEHLE 1953) . The conductor has no large bulb on the ventral side ( KUZMIN & ESYUNIN 2016) and in A. subnigra there is a tuft of thick hair in the dorsal side of the tibia that is missing in A. patula ( Fig. 4 ). The published information about the ecology of the species is somewhat confusing since it can be found from wet to dry habitats, mostly seashores ( WIEHLE 1953, ROBERTS 1985, FINCH 2008). In our study, we found it in the very wet (groundwater) field of Carex spp . (habitat F). An important environmental factor for the species could be the sandy soil rather than the saline impact ( WIEHLE 1953). The species is critically endangered in the Czech Republic, vulnerable in Slovakia, near threatened in Finland and least concern in Sweden.

Figures

Fig. 4. Argenna patula, male palp: A = conductor of the right, expanded palp, B = left palp, retrolateral. Scale bars: 0.1 mm for A, 0.5 mm for B