Chaerilobuthus Lourenço and Beigel, 2011

Xuan, Qiang, Prendini, Lorenzo, Engel, Michael S., Cai, Chenyang & Huang, Diying, 2025, Extinct scorpion family Chaerilobuthidae from Mid-Cretaceous Burmese amber reinterpreted as subfamily of extant family Pseudochactidae (Chelicerata: Scorpiones), Zoological Journal of the Linnean Society 203 (1), pp. 1-60 : 3-5

publication ID	https://doi.org/10.1093/zoolinnean/zlae169
DOI	https://doi.org/10.5281/zenodo.14831468
persistent identifier	https://treatment.plazi.org/id/700187A3-FFD7-FFC5-FCA3-FD7CB1DCF808
treatment provided by	Plazi
scientific name	Chaerilobuthus Lourenço and Beigel, 2011
status

Treatment

Genus Chaerilobuthus Lourenço and Beigel, 2011

( Figs 4–39 View Figure 4 View Figure 5 View Figure 6 View Figure 7 View Figure 8 View Figure 9 View Figure 10 View Figure 11 View Figure 12 View Figure 13 View Figure 14 View Figure 15 View Figure 16 View Figure 17 View Figure 18 View Figure 19 View Figure 20 View Figure 21 View Figure 22 View Figure 23 View Figure 24 View Figure 25 View Figure 26 View Figure 27 View Figure 28 View Figure 29 View Figure 30 View Figure 31 View Figure 32 View Figure 33 View Figure 34 View Figure 35 View Figure 36 View Figure 37 View Figure 38 View Figure 39 )

Chaerilobuthus Lourenço and Beigel, 2011: 635–639 , figs 1–11. Type species: Chaerilobuthus complexus Lourenço and Beigel, 2011: 635–639 , figs 1–11.

Chaeriloiurus Lourenço, 2020: 34–50, figs 13–22, synon. nov. Type species: Chaeriloiurus brigittemuellerae Lourenço, 2020: 34–50 , figs 13–22 [= Chaerilobuthus brigittemuellerae ( Lourenço and Velten, 2020) , comb. nov.].

Serratochaerilobuthus Lourenço, 2024: 1–6. figs 1–12, synon. nov. Type species: Serratochaerilobuthus schmidti Lourenço, 2024: 1–6 . figs 1–12 [= Chaerilobuthus schmidti (Lourenço and Velten, 2024) , comb. nov.].

Diagnosis: The species of Chaerilobuthus share many characters with the extant family Pseudochactidae , notably: sternum pentagonal ( Figs 12B View Figure 12 , 15B View Figure 15 , 20E View Figure 20 , 23B View Figure 23 , 26B View Figure 26 , 28B View Figure 28 , 33B View Figure 33 , 34D View Figure 34 , 37F View Figure 37 ); cheliceral moveable finger basal teeth absent; moveable finger ventral surface with serrula ( Figs 6C View Figure 6 , 12G View Figure 12 , 18F View Figure 18 , 23C View Figure 23 , 29B View Figure 29 , 34B View Figure 34 , 37B View Figure 37 ); median denticle rows of pedipalp chela fingers comprising oblique subrows ( Figs 13C View Figure 13 , 15E View Figure 15 , 29F View Figure 29 , 33C View Figure 33 ); pedipalps with Type D trichobothrial pattern, β configuration; trichobothrium d 2 situated on femur dorsal surface, angle formed by d 1, d 3, and d 4 opening toward prolateral surface ( Figs 7 View Figure 7 , 10 View Figure 10 , 13 View Figure 13 , 16 View Figure 16 , 21 View Figure 21 , 24 View Figure 24 , 26 View Figure 26 , 31 View Figure 31 , 35 View Figure 35 , 38 View Figure 38 ); legs with prolateral and retrolateral pedal spurs present, legs III and IV with tibial spurs absent ( Figs 6I–L View Figure 6 , 7F–I View Figure 7 , 12K, L View Figure 12 , 15G View Figure 15 , 18C View Figure 18 , 20J, K View Figure 20 , 23J, K View Figure 23 , 29G–J View Figure 29 , 33C, D, G, H, K View Figure 33 , 34I–L View Figure 34 , 37D View Figure 37 ), and telotarsi each with two rows of ventrosubmedian spinules ( Figs 6J–L View Figure 6 , 9G, I View Figure 9 , 23J, K View Figure 23 , 29H, J View Figure 29 ); metasomal segment V with paired ventrosubmedian carinae ( Figs 5F View Figure 5 , 9N View Figure 9 , 20L View Figure 20 , 33I, J View Figure 33 , 35I View Figure 35 ); telson without subaculear tubercle ( Figs 5F View Figure 5 , 9N View Figure 9 , 14B View Figure 14 , 18G View Figure 18 , 19B View Figure 19 , 33I, J View Figure 33 , 37I View Figure 37 ).

The extinct genus may be distinguished from other pseudochactid scorpions by the following combination of characters: carapace anterior margin sublinear, anterolateral margins entire, posterolateral margins angular, slanting, posteromedian margin slightly recurved ( Figs 6A View Figure 6 , 9A View Figure 9 , 12A View Figure 12 , 15A View Figure 15 , 20B View Figure 20 , 23A View Figure 23 , 26A View Figure 26 , 28A View Figure 28 , 34A View Figure 34 , 37A View Figure 37 ); carapace circumocular sutures absent ( Figs 6A View Figure 6 , 9A View Figure 9 , 12A View Figure 12 , 15A View Figure 15 , 20B View Figure 20 , 23A View Figure 23 , 26A View Figure 26 , 28A View Figure 28 , 34A View Figure 34 , 37A View Figure 37 ); median ocelli absent and one pair of large posterolateral major lateral ocelli present ( Figs 6A View Figure 6 , 9A View Figure 9 , 12A View Figure 12 , 15A View Figure 15 , 18D View Figure 18 , 20A, B View Figure 20 , 23A View Figure 23 , 26A View Figure 26 , 28A View Figure 28 , 29A View Figure 29 , 33A View Figure 33 , 34A, C View Figure 34 , 37A, C View Figure 37 ); pedipalp femoral trichobothria d 3 and d 4 situated closer to midpoint of segment ( Figs 7A View Figure 7 , 10 View Figure 10 , 13A View Figure 13 , 16 View Figure 16 , 24A View Figure 24 , 26D View Figure 26 , 31 View Figure 31 , 35C, J View Figure 35 ) and d 3 – d 4 axis directed slightly away from retrodorsal carina rather than parallel to it (β configuration) ( Figs 7A View Figure 7 , 10 View Figure 10 , 13A View Figure 13 , 16 View Figure 16 , 24A View Figure 24 , 26D View Figure 26 , 31 View Figure 31 , 35C, J View Figure 35 ); pectines with low tooth counts (five to eight teeth) ( Figs 6D View Figure 6 , 12B View Figure 12 , 15D View Figure 15 , 18I View Figure 18 , 20G View Figure 20 , 23F View Figure 23 , 26B View Figure 26 , 29C View Figure 29 , 33B View Figure 33 , 34G View Figure 34 , 37H View Figure 37 ).

Additionally, two new characters, considered diagnostic for Chaerilobuthus , are shared with the extant pseudochactid, Qianxie solegladi ( Tang, 2022: 7, 11, figs 10 43–46): leg I maxillary lobes (coxapophyses) anterior margins with serrula ( Fig. 38 View Figure 38 ); leg basitarsi with pair of spinule rows distally ( Figs 6I–L View Figure 6 , 9F–I View Figure 9 , 12H, L View Figure 12 , 15G View Figure 15 , 18C View Figure 18 , 20J, K View Figure 20 , 23K View Figure 23 , 29G–J View Figure 29 , 33G, H View Figure 33 , 34I–L View Figure 34 ).