New record of Chaetophiloscia hastata Verhoeff, 1928 for Georgia (Isopoda, Oniscidea, Philosciidae)

Chaetophiloscia hastata Verhoeff, 1928 is recorded from Saskhori limestone quarry (Mtskheta municipality, eastern Georgia). This is the first confirmed record of the genus and species for the Georgian isopod fauna. The species is fully illustrated to facilitate its identification


Introduction
Caucasian isopod fauna is poorly investigated and only 35 species of Oniscidea in 19 genera and 8 families are recorded from Georgia (Schmalfuss 2003;Kuznetsova and Gongalsky 2012;Khisametdinova and Schmalfuss 2012;Barjadze et al. 2015Barjadze et al. , 2019;;Turbanov et al. 2016;Arsenashvili et al. 2022).To date, no species in the family Philosciidae have been recorded from the country.Recent investigations in the area of the Saskhori limestone quarry (Mtskheta municipality, Georgia) revealed the presence of Chaetophiloscia hastata Verhoeff, 1928 which was already recorded in other Caucasian countries.

Materials and methods
Specimens were sampled using pitfall traps containing formalin and stored in 70% alcohol.Species identification followed the descriptions and figures provided by various authors (Verhoeff 1929;Radu 1959Radu , 1960;;Dalens 1973;Schmalfuss 1990;Giurginca and Vănoaica 2002).The species is here illustrated with the aid of a camera lucida mounted on Wild M5 and Wild M20 microscopes.Figures were digitally drawn with the program Microsoft powerpoint 2013, Irfanview and Adobe Photoshop CS6.The specimens examined are deposited in the collections of the Institute of Zoology at Ilia State University, Tbilisi, Georgia (ISUIZ) and the Museum of Natural History, Zoology Section "La Specola", of the University of Florence, Italy (MZUF).

Discussion
The genus Chaetophiloscia comprises with certainty 17 species mainly distributed in the countries bordering the Mediterranean and Black Sea (Schmalfuss 2003) (Table 1).Only a few species have been introduced into other parts of the world, e.g., C. sicula Verhoeff, 1908 in USA (Hornung and Szlávecz 2003) and in greenhouses in England (Gregory 2014).Other five species presently included in the genus certainly do not belong to Chaetophiloscia but their re-examination is necessary for placement in a correct genus: C. frontalis Lemos de Castro, 1967 from Brazil, C. gatunensis (Van Name, 1926) from Costa Rica, Panama and supposed- C. illyrica (Verhoeff, 1901) Croatia 10 C. kinzelbachi Schmalfuss, 1986 Turkey; Syria 11 C. lagoi (Arcangeli, 1934) Greece; Cyprus 12 C. leucadia Strouhal, 1936 Greece 13 C. penteliconensis (Verhoeff, 1901) Greece 14 C. sicula Verhoeff, 1908 Canary Is; Spain; France; Italy; Romania; Greece; Crimea; USA; England 15 C. splitensis Verhoeff, 1930 Croatia 16 C. warburgi Schmalfuss, 1991 Israel 17 C. weisi Schmölzer, 1965 Spain Even if Chaetophiloscia hastata is well characterized from the descriptions and figures given by previous authors, it is fully illustrated here (Figs.1-5) to provide a comparison with all the other species in the genus.The species is readily distinguishable by the enlarged carpus of the male pereopod 1 (Fig. 4A) and, to a lesser extent, 2, and the extreme elongation of the male pleopod 2 endopod (Fig. 5A) and male pleopod 5 exopod (Fig. 5D).These characters of C. hastata might suggest its inclusion in a distinct genus but all the other characters present in the type-species Chaetophiloscia elongata (Dollfus, 1984) and in the other species of the ge-nus seem to confirm its belonging to the genus Chaetophiloscia.These characters are the position of the noduli laterales (Fig. 2A) with the d/c coordinates showing a maximum on pereonite 4, the cephalon (Fig. 2B) with suprantennal line and no frontal line, the pleon (Fig. 1A, B) narrower than pereon with epimera reduced, the mandibles (Fig. 3A,B) with molar penicil dichotomized, the maxillula (Fig. 3C) with the inner set of teeth apically cleft, and the maxilliped (Fig. 3E) endite without penicil.
In the Caucasus area, Chaetophiloscia hastata was previously recorded only from Azerbaijan by Schmalfuss (1990) and from southern Russia (Abrau Peninsula and Sochi) by Verhoeff (1933) and Gongalsky and Kutznetsova (2011).Furthermore, C. hastata was reported from the     Batumi (Georgia) area on April 8, 2022, according to the iNaturalist website (https://www.inaturalist.org/observations/110758777).However, this record should be considered doubtful, because it was determined just based on photos, where the main characters to identify the species cannot be visible.Hence, the Saskhori limestone quarry represents the first confirmed record of both the genus and species for Georgia.Given the high similarity of specimens photographed in Batumi's surroundings to C. hastata, we believe the species may also occur along Georgia's Black Sea coast and may be more widespread throughout the country.

Table 1 .
List of species of Chaetophiloscia with their distributions.