Mesolimulus walchi DESMAREST, 1822

Taxonomy

Horseshoe crab

Kingdom: ANIMALIA
Phylum: ARTHROPODA Latreille 1829
Class: XIPHOSURA Latreille, 1802
Order: XIPHOSURIDA Latreille, 1802
Family: Limulidae Zittel, 1885
Genus: Mesolimulus
Species: Mesolimulus walchi
Author Citation DESMAREST, 1822

Geological Time Scale

Eon: Phanerozoic
Era: Mesozoic
Period: Jurassic
Sub Period: None
Epoch: Late
International Age: Tithonian (late)

Stratigraphy

Weissjura Group
Altmühltal Formation

Biostratigraphy

Hybonoticeras hybonotum Zone
Subplanites ruepellianus Zone

Provenance

Acquired by: Purchase/Trade

Dimensions

Length: 18 cm

Location

Solnhofen, Untere Haardt
Eichstätt
Bavaria
Germany

• jurassic
• solnhofen
• tff-oilshale-ar113
• tithonian

Comments

Mesolimulus walchi in dorsal preservation with (poorly) retained "death trace".

Taxonomy from Russel et al. 2021.

Russel et al. 2021, p. 6: "Emended diagnosis. Prosoma semi-circular, genal spines without indentations that terminate at a first fifth of thoracetron. Cardiac lobe cone-shaped with crenulated margins and cardiac ridge. Ophthalmic ridges present and do not curve towards lateral prosomal margins. Posterior prosomal rim pronounced and lacks beads along margin. Occipital bands present and pronounced. Thoracetron trapezoidal and has pronounced flange. Lateral margin ridges absent. Moveable spine notches present and pronounced. Moveable spines long. Medial lobe triangular, has ridge and spines on ridge. Terminal thoracetronic spines medium sized and posterolaterally directed. Telson embayment strongly concave. Telson keeled. “

References:
Russell D. C. Bicknell; Błażej Błażejowski; Oliver Wings; Tomaž Hitij; Mark L. Botton (2021). Critical re‐evaluation of Limulidae uncovers limited Limulus diversity. Papers in Palaeontology, pp. 1-32.  doi:10.1002/spp2.1352 
D. R. Lomax & Ch. A. Racay (2012). A Long Mortichnial Trackway of Mesolimulus walchi from the Upper Jurassic Solnhofen Lithographic Limestone near Wintershof, Germany. ICHNOS - International Journal for Plant and Animal Traces 01/2012; 19(3):175-183. DOI:10.1080/10420940.2012.702704
J. C. Lamsdell (2016). Horseshoe crab phylogeny and independent colonizations of fresh water: Ecological invasion as a driver for morphological innovation - Palaeontology (59), 181-194.