Genus Leiobunum C.L. Koch, 1839

Type species

Designation by Thorell, 1876: Opilio fasciatus Herbst, 1798 = Leiobunum rotundum (Latreille, 1798) .

Remark

Of the representative material investigated, we found the four hypothesized species well separable upon a number of somatic and male genital morphological characters, which are summarized in Table 1 for convenient use. Species appear largely allopatric, except for L. subalpinum, which is firmly nested within the area of L. rupestre . In addition, parapatric and locally sympatric occurrences of two species under discussion in East-Central Europe cannot be excluded, especially in South Poland, the central Alps and close to the Czech/Slovak border area (Fig. 2).

Leiobunum subalpinum Komposch, 1998 is considered most closely related to L. rupestre (Komposch 1998) and, as such, is also regarded as a member of the L. rupestre species group. As it is easily discriminated from all discussed forms by its dark coxal markings and, apart from L. rupestre, by its restricted alpine range, it is not featured here (see Komposch 1998; Komposch & Gruber 2004 for

details) except for general remarks; its geographic range is indicated in Fig. 2. In addition, the poorly known Leiobunum nigripalpe Simon, 1889, described from the western Alps (France), was reinvestigated. However, the type series represents a composite collection of at least two different small Nelima Roewer species, both unaffiliated to the L. rupestre species group. This holds true, too, for the specimen depicted as Leiobunum nigripalpe in Martens (1978), representing a yet to be identified Leiobunum species.