Diversity of schizomids (Arachnida: Schizomida) revealed by new fossil genera and species from mid-Cretaceous Burmese amber with implications for a Gondwanan origin of the Burma Terrane Author Magnussen, Ilian De Francesco Author Müller, Sandro P. Author Hammel, Jörg U. Author Kotthoff, Ulrich Author Harms, Danilo text Zoological Journal of the Linnean Society 2022 2022-05-24 196 792 844 journal article 218957 10.1093/zoolinnean/zlac034 466f2ee8-5046-4082-82fc-5955b08410f5 0024-4082 7187082 26533E9F-C53F-4051-B6B4-990E63C08C74 † MUELLERIZOMUS AMANDAE DE FRANCESCO MAGNUSSEN & S.P. MÜLLER SP. NOV. ( FIGS 27–31 ) Zoobank registration: urn:lsid:zoobank.org:act: 63A0355B-C647-414E-8C0F-2C5BD807495E Type material: Holotype ( Fig. 27 A – D ), adult homeomorphic ♂ , collection no. GPIH04895 , ex collection Patrick Müller (no. BUB3553 ); paratype ( Fig. 29A–D ), adult ♀ , GPIH04892 , ex collection Patrick Müller (no. BUB557 ). Remarks The female specimen is matched with the male holotype of † Mu. amandae because both share the following characters: propeltidium with a single median seta followed by three pairs of setae; corneate eyes or eyespots absent; body without clavate setae; anterodorsal margin of femur of leg IV produced at an angle of ~90°; tergite II with one pair of setae; tergites X–XII not elongated. Diagnosis † Muellerizomus amandae differs from its congener † Mu. palicaudatus by the lack of eyespots and a more rounded male flagellum shape. Etymology The specific epithet name is a patronym for Dr Amanda Eva Bauzá Iraola, former directorial assistant of the Center of Natural History in Hamburg , for her outstanding commitment to staff and collectionbased science during the past years. It is feminine in gender. Description Total length from anterior dorsal process to base of the flagellum 1.83 mm . Colour (in amber): Golden brown; prosoma and pedipalps with a slightly darker touch of brown than the opisthosoma; femur and patella of leg IV light brown; all the other legs and flagellum golden yellowish and translucent. Figure 24. Specimen GPIH04986 , † Mesozomus groehni , holotype. A, specimen in dorsal view, photograph. B, same, interpretative drawing. C, specimen in ventral view, photograph. D, same, interpretative drawing. See Material and methods for explanation of abbreviations. Scale bars: 1 mm. Modified after Müller et al. (2019) . Figure 25. Specimen GPIH04986 , † Mesozomus groehni , holotype details. A, specimen in dorsal view, three-dimensional (3D) model. B, specimen in ventral view, 3D model. See Material and methods for explanation of abbreviations. Scale bar: 1 mm. Modified after Müller et al. (2019) . Prosoma: Length 0.80 mm ; propeltidium length 0.47 mm , width 0.27 mm . Anterior process much rounded, without tip, length 0.03 mm ; setation: one seta on the right side of the anterior process, which implies an aborted seta on the left, but definite setation remains unclear. Further propeltidium setation: a single median seta followed by three pairs of setae ( paratype Fig. 30A, B ). Neither corneate eyes nor eyespots present. Mesopeltidia and metapeltidium compressed owing to taphonomic processes to the point where the dimensions cannot be measured. Ventral side of the prosoma pressed inwards into the propeltidium. Anterior sternum: not entirely visible, with more than 3 + 2 sternapophysial setae, length and width not measurable owing to the compression of the ventral side of the prosoma. Posterior sternum not visible. Chelicerae: Setation of the mesal side of chelicerae not visible, except for G6-1. Pedipalps: Without armature, mesal spur not visible; trochanter hardly visible, setation: three+ strong setae ventral; femur: setation: two+ dorsal, two+ dorsoectal, two+ dorsomesal; patella: setation: four ventromesal, two mesal, four dorsomesal, three ectal, three dorsal; tibia: shorter than patella, setation: five dorsal, three ventromesal, four dorsoectal, three ventral; tarsus: with small, thin, asymmetrical tarsal spurs, spur length 0.01 mm , setation: two+ dorsal, four dorsomesal, four mesal; claw: bent downwards, slightly longer than half the length of tarsus. Figure 26. Specimen GPIH04986 , † Mesozomus groehni , holotype details. A, flagellum in dorsal view, photograph. B, same, interpretative drawing. Scale bar: 0.5 mm. C, right pedipalp in ectal view, photograph. D, same, interpretative drawing. See Material and methods for explanation of abbreviations. Scale bars: 0.5 mm (A, B, D); 1 mm (C). Modified after Müller et al. (2019) . Legs: Legs I well preserved and complete on each side, tarsus with six segments, leg I ~1.42 times longer than the body; anterodorsal margin of femur of leg IV produced at an angle of ~90°, femur of leg IV 2.71 times longer than deep, leg IV 1.19 times longer than the total body length, leg formula: 1423. Opisthosoma: Length 1.03 mm , width 0.51 mm ; segments XI – XII partly retracted into the opisthosoma, XII with a posterodorsal process, slightly bent upwards. Abdominal tergites setation: I–VIII: Dm; IX: Dl1; X: not visible; XI: Dl1, XII: Dm, Dl1, setation pattern: 2:2:2:2:2:2:2:2:2:?:2:4. Flagellum of male: dorsoventrally flattened, nearly round and flat, with an apical tip at the posterior end, two small depressions near the posterior end on the dorsal side of the flagellum ( Fig. 28A–D ), length 0.22 mm , width 0.21 mm ; stalk length 0.06 mm ; setation: Dm1, Dl2 paired, Dm4, Dl3 paired, Vm1, Vm2 paired, Vm3 paired, Vl1 paired, Vm5, Vl2 paired. Paratype female: Metapeltidium barely divided ( Fig. 30C, D ); pedipalp trochanter with mesal spur, claw slightly longer than half the length of the tarsus; body size 2.35 mm ; leg IV 0.89 times longer than the total body length, femur of leg IV 2.76 times longer than deep; flagellum with three annuli, flagellomeres I, II, III, V + VI ( Fig. 31A, B ), total length 0.27 mm , lengths of segments: 0.05 mm , 0.05 mm , 0.03 mm , 0.12 mm ; setation: Dm1, Dm4, Vm1 missing, Vm2 paired, left one probably lost, Vm3 paired, Vm5, Dl1 paired, right one lost, Dl2 paired, Dl3 paired, Dl4 absent, Vl1 paired, Vl2 paired. Holotype further measurements: Pedipalp: trochanter not measurable; femur not measurable; patella 0.28 mm ; tibia 0.17 mm ; tarsus 0.12 mm ; claw 0.07 mm ; total length not measurable. Leg I: trochanter 0.14 mm ; femur 0.68 mm ; patella 0.55 mm ; tibia 0.7 mm ; metatarsus 0.21 mm ; tarsus (tarsus segments) 0.31 mm ( 0.03 mm ; 0.04 mm ; 0.04 mm ; 0.03 mm ; 0.05 mm ; 0.12 mm ); total length 2.59 mm . Leg II: trochanter> 0.05 mm ; femur 0.41 mm ; patella 0.26 mm ; tibia 0.26 mm ; metatarsus 0.25 mm ; tarsus (tarsus segments) 0.22 mm ( 0.09 mm ; 0.06 mm ; 0.07 mm ); total length> 1.45 mm . Leg III: trochanter 0.13 mm ; femur 0.34 mm ; patella 0.21 mm ; tibia 0.22 mm ; metatarsus 0.24 mm ; tarsus (tarsus segments) 0.22 mm (not measurable); total length 1.36 mm . Leg IV: trochanter 0.16 mm ; femur 0.65 mm ; patella 0.24 mm ; tibia 0.45 mm ; metatarsus 0.39 mm ; tarsus (tarsus segments) 0.29 mm ( 0.12 mm ; 0.06 mm ; 0.11 mm ); total length 2.18 mm . Figure 27. Specimen GPIH04895 , † Muellerizomus amandae , sp. nov. , holotype. A, specimen in dorsal view, photograph. B, same, interpretative drawing. C, specimen in ventral view, photograph. D, same, interpretative drawing. See Material and methods for explanation of abbreviations. Scale bars: 1 mm. Figure 28. Specimen GPIH04895 , † Muellerizomus amandae , sp. nov. , holotype details. A, male flagellum in dorsal view, photograph. B, same, interpretative drawing. C, male flagellum in ventral view, photograph. D, same. interpretative drawing. See Material and methods for explanation of abbreviations. Scale bars: 0.25 mm. Paratypefurthermeasurements: P edipalp:trochanterand femur not measurable; patella 0.25 mm ; tibia 0.34 mm ; tarsus 0.17 mm ; total length not measurable. Leg I: trochanter 0.18 mm ; femur 0.59 mm ; patella 0.72 mm ; tibia 0.53 mm ; metatarsus 0.20 mm ; tarsus 0.33 mm ; total length 2.55 mm . Leg II: trochanter 0.13 mm ; femur 0.41 mm ; patella 0.27 mm ; tibia 0.32 mm ; metatarsus 0.24 mm ; tarsus 0.26 mm ; total length 1.63 mm . Leg III: trochanter 0.16 mm ; femur 0.43 mm ; patella 0.10 mm ; tibia 0.19 mm ; metatarsus 0.22 mm ; tarsus 0.17 mm ; total length 1.27 mm . Leg IV: trochanter 0.25 mm ; femur 0.72 mm ; patella 0.19 mm ; tibia 0.34 mm ; metatarsus 0.32 mm ; tarsus 0.28 mm ; total length 2.10 mm .