Wednesday, November 17, 2021

[Arachnida • 2021] Chthonius kirghisicus • A New Cave-dwelling Species (Pseudoscorpiones, Chthoniidae) from Kyrgyzstan


Chthonius kirghisicus 
Prado, Viana, Milko & Ferreira, 2021


Abstract
A new pseudoscorpion species, Chthonius kirghisicus sp. nov., is described. It can be distinguished from the other species of the genus mainly by the number and shape of chelal teeth, the number of coxae setae, the arrangement of carapacal setae, and its measurements. This new species represents the first record for the genus in Kyrgyzstan. We also provide recommendations for future research on this species.

Keywords: Cave-dwelling, pseudoscorpion, taxonomy


Figure 6. Type locality and habitat of Chthonius kirghisicus sp. nov.
A Kyrgyzstan karst landscape B general area where the cave is located with the lower entrance featured C detail of the lower cave entrance D cave interior E live holotype.

Family Chthoniidae Daday, 1888
Genus Chthonius C.L. Koch, 1843

Chthonius kirghisicus sp. nov.
 
Etymology: The epithet kirghisicus is an adjective that refers to the country where the specimens were collected, Kyrgyzstan.

Diagnosis: Chthonius kirghisicus sp. nov. differs from other members of the subgenus by the following combination of characters: one pair of eyes (C. tadzhikistanicus with four feebly small eyes, C. aquasanctae with two eyespots, C. pagus and C. submontanus bearing two anterior well-developed eyes and two posterior eyespots, C. shelkovnikovi, C. carinthiacus, C. delmastroi and C. tenuis with four well developed eyes, C. azerbaidzhanus and C. satapliaensis lack eyes or eye spots) (Redikorzev 1930; Schawaller and Dashdamirov 1988; Dashdamirov and Schawaller 1992; Gardini 2009; Christophoryová et al. 2011; Ćurčić et al. 2011, 2012a); epistome large and heavily dentated (C. azerbaidzhanus, C pagus and C. satapliaensis with small dentated epistome, C. carinthiacus and C. aquasanctae with a distinct but small epistome, C. ponticus, C. delmastroi, C. tenuis and C. submontanus without an epistome) (Beier 1964; Schawaller and Dashdamirov 1988; Gardini 2009; Christophoryová et al. 2011; Ćurčić et al. 2011, 2012a); anterior margin mostly serrated (ranging between seta ame and al) (C. tadzhikistanicus with anterior margin entirely serrated, C. azerbaidzhanus, C. satapliaensis, C. pagus, C. aquasanctae, C. carinthiacus and C. ponticus with only epistome region serrated) (Beier 1964; Schawaller and Dashdamirov 1988; Christophoryová et al. 2011; Ćurčić et al. 2011, 2012a); carapace with 20 setae, chaetotaxy 4: 2: 4: 4: 2: 4 (C. ponticus [4: 4: 2: 4: 2: 2], C. carinthiacus, C. delmastroi, C. tenuis and C. submontanus [4:6:4:2:2] with 18 setae); il located medially (in C. tadzhikistanicus, C. shelkovnikovi and C. azerbaidzhanus il is situated on the lateral margin), pl situated posteriorly to pm (in C. satapliaensis pl is located anteriorly to pm); palpal femur 5.2 times longer than wide (4.5 times in C. tadzhikistanicus, 3.0 times in C. shelkovnikovi, 5.4 times in C. azerbaidzhanus and 6.1 times in C. satapliaensis); chela 5.8 times longer than wide (5.4 times in C. tadzhikistanicus, 5.1 times in C. satapliaensis, 4.0 times in C. shelkovnikovi and 5.1 times in C. ponticus, 4.9 times in C. aquasanctae, 4.4 times in C. delmastroi, 5.3 times in C. tenuis, 4.5 times in C. submontanus and 4.8 times in C. pagus) (Redikorzev 1930; Beier 1964; Dashdamirov and Schawaller 1992; Gardini 2009; Ćurčić et al. 2011, 2012a); fixed chelal finger with 75–77 contiguous, acute and reclined backwards teeth (25 acute and straight teeth in C. azerbaidzhanus, 28 in C. satapliaensis, 33–38 acute, reclined backwards and close-set teeth in C. carinthiacus, 23–25 in C. aquasanctae, 30–33 in C. pagus, 32–36 in C. submontanus, 38 in C. tenuis, and 27–29 in C. delmastroi; 12–13 acute and sparse teeth in C. ponticus and 50 round and small teeth in C. shelkovnikovi); movable finger with 59–60 contiguous acute and retrorse teeth (18 acute and small teeth in C. azerbaidzhanus, 18 acute and straight teeth in C. satapliaensis, 17–20 acute, reclined backwards and close-set teeth in C. carinthiacus, 19–21 in C. aquasanctae, 25–39 in C. pagus, 23–30 in C. submontanus, 34 in C. tenuis, 26–29 in C. delmastroi; 24 flat and small teeth in C. ponticus and 50 round and small teeth in C. shelkovnikovi); absence of a protuberance near ib and isb (found in C. tadzhikistanicus C. tenuis and C. delmastroi); chelal hand long and slender (C. ponticus presents a ventrally round portion of the hand, C. shelkovnikovi exhibits short and robust chela) (Redikorzev 1930; Beier 1964; Schawaller and Dashdamirov 1988; Dashdamirov and Schawaller 1992; Gardini 2009; Christophoryová et al. 2011; Ćurčić et al. 2011, 2012a).


 Guilherme C. Prado, Ana Clara M. Viana, Dmitry A. Milko and Rodrigo L. Ferreira. 2021. Chthonius kirghisicus (Pseudoscorpiones, Chthoniidae), A New Cave-dwelling Species from Kyrgyzstan. Subterranean Biology. 40: 27-41. DOI: 10.3897/subtbiol.40.67303