Chaerilobuthus hansgeorgmuelleri Lourenco 2019
Creators: name: Xuan, Qiang
name: Prendini, Lorenzo
name: Engel, Michael S.
name: Cai, Chenyang
name: Huang, Diying
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Scorpiones
Chaerilobuthidae
Chaerilobuthus
Chaerilobuthus hansgeorgmuelleri

description: Chaerilobuthus hansgeorgmuelleri Lourenço, 2019
(Figs 25–26, 39)
Chaerilobuthus hansgeorgmuelleri Lourenço, 2019 in Lourenço and Velten, 2019: 2–10, figs 1–8.
Type material: Holotype: one juv. ♀ (personal collection of Hans-Georg Müller, Gelsenkirchen, Germany), Cretaceous (Cenomanian) burmite: MYANMAR: Kachin State (precise locality unknown).
Diagnosis: Thefollowingcombinationofcharactersisdiagnosticfor C. hansgeorgmuelleri: carapace length less than posterior width (Fig. 26A); carapace anterior margin slightly depressed submedially (Fig. 26A); lateral ocelli protruding (Fig. 26A); sternum relatively wide (Fig. 26B); pectines each with five teeth (Fig. 26B); pedipalp patella trichobothrium i aligned with trichobothrium d 3 (Fig.26F); pedipalp chela robust, manus globose, ratio of chela length: chela manus width less than 3 (Fig. 26C).
Description: Based on the material examined (NIGP 201164).
Carapace: Length less than posterior width (L/ PW = 0.94). Anteromedian depression narrow, shallow; anterosubmedial depressions absent; lateral ocular carinae absent; posteromedian and posteromarginal sulci distinct; surfaces almost smooth to sparsely and finely granular (Fig. 26A). Median ocular tubercle situated anteromedially; median ocelli absent; one pair of large posterolateral major lateral ocelli present.
Coxosternal region: Surface smooth, sparsely covered in macrosetae (Figs 25B, 39G). Leg I maxillary lobes (coxapophyses) distal margins slightly curved, dilate anteriorly and adorned with serrula comprising c. 15–25 denticles (Fig. 39G). Sternum broad, pentagonal; lateral margins sublinear, parallel; ventral surface flat, without distinct concave region or median sulcus; posteromedian depression wide, shallow (Fig. 26B).
Chelicerae: Fixed finger and manus, prolateral and ventral surfaces each with numerous long, dense macrosetae (Fig. 25A). Cheliceral dentition not clearly visible.
Pedipalps: Segments moderately robust; surfaces sparsely covered by short microsetae (Fig. 25A). Femur with three carinae evident; dorsalsurfacewithseveralcoarsegranules;prodorsalandproventral carinae distinct, serrate; retrodorsal carinae distinct, smooth, and costate (Fig. 26D). Patella with five carinae evident; prodorsal carina distinct, costate-granular; prolateral surface, dorsoventral ‘vaulted’ projection (‘anterior process’) distinct with moderately developed pair of apophyses or tubercles (‘patellar spurs’), each possessing one macroseta; retrodorsal and retroventral carinae smooth, costate (Figs 25B, 26F). Chela relatively robust (CL/ CW = 2.62, Appendix 2); manus globose; chela with six carinae evident; digital carina complete, distinct; dorsomedian carina moderately distinct, costate at base of fixed finger to medially on manus, becoming obsolete proximally on manus; prodorsal carina distinct, comprising several prominent spiniform granules, promedian and proventral carinae obsolete, each comprising few isolated granules; retroventral carina obsolete; dorsal secondary, subdigital, retromedian, and ventromedian carinae absent or obsolete (Figs 25A, B, 26C). Chela finger dentition not visible. Trichobothrial pattern Type D, β configuration. Femur with 11 trichobothria, five d, three i, and three e trichobothria; trichobothrium e 1 situated proximal to trichobothrium d 3; trichobothrium e 3 situated dorsal to trichobothrium d 6 (Fig. 26D). Patella with 10 trichobothria, including three d, one i, and two e trichobothria; trichobothrium i 1 aligned with trichobothrium d 3 (Fig. 26F). Chela with 12 trichobothria; fixed finger with two d, three i, and two e trichobothria; manus with four e and one v trichobothria; trichobothrium Et 1 situated distally on manus, almost aligned with, or proximal to, moveable finger condyle; trichobothrium eb situated on fixed finger, slightly distal to moveable finger condyle; trichobothrium esb situated medially on fixed finger; trichobothrium V 2 situated distally on manus and near retroventral carina (Fig. 26C).
Pectines: Basal piece not visble (Fig. 26B). Three marginal lamellae and four median lamellae; longitudinal suture between marginal and median lamellae distinct. Fulcra absent or obsolete. Teeth rounded, peg sensilla not visible.
Genital operculum: Two opercular sclerites narrow and completely separated (Fig. 26B).
Material examined: MYANMAR: Kachin State: Noije Bum near Hukawng Valley, precise locality unknown, Cretaceous (Cenomanian) burmite: one subad. (sex unknown), mesosoma and metasoma absent (NIGP 201164).
description: Published as part of 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), pp. 1-60 in Zoological Journal of the Linnean Society 203 (1) on pages 31-34, DOI: 10.1093/zoolinnean/zlae169, http://zenodo.org/record/14831464