Leucogeorgia, Verhoeff, 1930

Antić, Dragan Ž. & Reip, Hans S., 2020, The millipede genus Leucogeorgia Verhoeff, 1930 in the Caucasus, with descriptions of eleven new species, erection of a new monotypic genus and notes on the tribe Leucogeorgiini (Diplopoda: Julida: Julidae), European Journal of Taxonomy 713, pp. 1-106 : 85-89

Additional Leucogeorgia material examined

We have also examined some females and juveniles of the genus Leucogeorgia from several other caves, but we do not dare assign them to any of the species treated above ( Figs 57–58 ). Species with modified mouthparts were found in Mchishta (= Akshasha) Cave (43.24° N, 40.51° E) and Kelasurskaya Cave (43.02° N, 41.14° E). Species with normal mouthparts were found in Nizhnyaya Shakuranskaya Cave (43.03° N, 41.33° E), Tkibula-Dzevrula Cave (42.34° N, 42.99° E), Nikortsminda Cave (42.46° N, 43.07° E), Bolshaya Kazachebrodskaya (= Verkhnyaya Mzymtinskaya = Akhshtyrskaya) Cave (43.52° N, 39.99° E), Zamshevaya Cave and Tsotne Dadiani Cave (42.75° N, 42.13° E) at the bottom of funnel 1 and at the bottom of funnel 2. These samples are deposited in the ZMUM collection.

Species richness estimation

Of our 16 Caucasian Leucogeorgiini species, L. prometheus sp. nov. and L. abchasica are the most widespread ones, with nine cave locations each. Four new species are known from only one cave (see Table 1 ). In most cases each species is represented by only a few specimens in each cave (except L. prometheus ). In total, we have 58 species-cave (locality) records, where caves with two species are counted twice.

The species richness estimation revealed a mean CHAO1-estimator of 18, with lower and upper 95% boundaries of confidence intervals of 16 and 32, respectively. This means that we could expect from 16 to 32 species of Leucogeorgiini in the western Caucasus, most likely 18 species. Thus, most probably only two species are yet to be discovered. Based on this species richness estimation, our revision has captured the species diversity of the Leucogeorginii almost completely.

It is discouraging that, according to the estimation, in order to locate these two missing species, probably another 41 localities inhabited by Leucogeorgiini species (in addition to the 58 already known locations) need to be investigated ( Fig. 52 ).

Figures

Fig. 57. Distribution of the northwestern group of the genus Leucogeorgia Verhoeff, 1930.

Fig. 58. Distribution of the southeastern group of the genus Leucogeorgia Verhoeff, 1930 and the species Martvilia parva gen. et sp. nov.

Fig. 52. Species estimation–extrapolated rarefaction curve. X-axis: cave location with species of Leucogeorgiini (each cave–species record counts separately); Y-axis: estimated number of species.