Chthonius C. L. Koch 1843
Creators: name: Gardini, Giulio
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Pseudoscorpiones
Chthoniidae
Chthonius

description: Key to adults of the Chthonius -related genera (coxae II and III with coxal spines)
[modified from Zaragoza (2017)]
1 Intercoxal tubercle absent............................................................................... 2
1’ Intercoxal tubercle present, bisetose....................................................................... 4
2 Trichobothrium sb of movable chelal finger placed approximately halfway between trichobothria b and st ............... 3
2’ Trichobothrium sb of movable chelal finger distinctly closer to st than to b, forming with st and t a separate group with respect to b ........................................................................ Spelyngochthonius Beier, 1955
3 Chela not lagyniform, fixed finger sigmoid in lateral view. Distal marginal seta on pedipalpal coxa distinctly longer than distal marginal seta on coxa I........................................................... Microchthonius Hadži, 1933
3’ Chela lagyniform, fixed finger straight in lateral view. Distal marginal seta on pedipalpal coxa markedly shorter than the distal marginal seta on coxa I...................................................... Cantabrochthonius Zaragoza, 2017
4 Male genitalia without median hiatus dividing each row of internal guard-setae.................................... 5
4’ Male genitalia with median hiatus dividing each row of internal guard-setae into two groups of two setae........................................................................................ Hesperochthonius Browning, 1970
5 Coxal spines of coxa II irregularly arranged in a rounded patch................................................. 6
5’ Coxal spines of coxa II arranged in a transverse row................................. Neochthonius Chamberlin, 1929
6 Chela not lagyniform, hand fusiform; chelal fingers usually with more or less close-set teeth, distinctly reclined backwards. Apodeme of movable chelal finger usually absent, rarely well developed......................................... 7
6’ Chela lagyniform; chelal fingers mostly with large, upright and well-spaced teeth. Apodeme of movable chelal finger usually well developed and strongly sclerotized.................................................................... 8
7 Apodeme of movable chelal finger absent. Antiaxial tooth (td) on tip of fixed chelal finger absent.................................................................................................... Chthonius C.L. Koch, 1843
7’ Apodeme of movable chelal finger well developed and strongly sclerotized. Antiaxial tooth (td) on tip of fixed chelal finger present.......................................................................... Zaragozachthonius n. gen.
8 Proximal portion of chelal hand with 4 setae in adults and tritonymphs, seta hp 3 present. Tip of fixed chelal finger of male, tritonymph and deutonymph usually without a deep hollow on paraxial face and subapical protuberance (sp) (sometimes present in Globochthonius); without a medial protuberance (ip) between chelal condyles................................ 9
8’ Proximal portion of chelal hand with 3 setae in adults and tritonymphs, seta hp 3 absent. Tip of fixed chelal finger of male, tritonymph and deutonymph with a deep hollow on paraxial face and subapical protuberance (sp); medial protuberance (ip) present between chelal condyles................................................. Ephippiochthonius Beier, 1930
9 Chelal hand distad of trichobothria ib-isb with a rounded hump and a marked hollow before base of movable finger; base of chelal hand without a pronounced hump dorso-paraxially; third tooth of normal row (mt) of fixed chelal finger modified in shape and deviated in orientation with respect to the other teeth; movable chelal finger lacking lyrifissures ma 1 and ma 2 ............................................................................. Occidenchthonius Zaragoza, 2017
9’ Chelal hand without a hump distad of trichobothria ib-isb, gradually constricted distad of trichobothria ib-isb and without hollow before base of movable finger; base of chelal hand with a pronounced hump dorso-paraxially; third tooth of normal row (mt) of fixed chelal finger neither modified in shape nor deviated in orientation with respect to the other teeth; lyrifissures ma 1 and ma 2 present on movable chelal finger......................................... Globochthonius Finnegan, 1932
description: Published as part of Gardini, Giulio, 2020, Zaragozachthonius (Pseudoscorpiones, Chthoniidae), a new genus with species in Italy and the Balkan peninsula, pp. 535-548 in Zootaxa 4894 (4) on page 537, DOI: 10.11646/zootaxa.4894.4.3, http://zenodo.org/record/4316705