Late Jurassic theropod dinosaur bones from the Langenberg Quarry (Lower Saxony, Germany) provide evidence for several theropod lineages in the central European archipelago

Abstract

Marine limestones and marls in the Langenberg Quarry provide unique insights into a Late Jurassic island ecosystem in central Europe. The beds yield a varied assemblage of terrestrial vertebrates including extremely rare bones of theropod from theropod dinosaurs, which we describe here for the first time. All of the theropod bones belong to relatively small individuals but represent a wide taxonomic range. The material comprises an allosauroid small pedal ungual and pedal phalanx, a ceratosaurian anterior chevron, a left fibula of a megalosauroid, and a distal caudal vertebra of a tetanuran. Additionally, a small pedal phalanx III-1 and the proximal part of a small right fibula can be assigned to indeterminate theropods. The ontogenetic stages of the material are currently unknown, although the assignment of some of the bones to juvenile individuals is plausible. The finds confirm the presence of several taxa of theropod dinosaurs in the archipelago and add to our growing understanding of theropod diversity and evolution during the Late Jurassic of Europe.

Keywords: Dinosauria; Harz Mountains; Langenberg Quarry; Late Jurassic; Lower Saxony Basin; Theropoda.

Figure 1. Geographic location of the Langenberg Quarry in the Harz Mountains of Germany.

(A) Map of Germany with the Harz Mountains highlighted in grey and Langenberg Quarry (LQ) indicated by star. (B) Close-up of the Harz Mountain area with Langenberg Quarry and nearby towns indicated.

Figure 2. Isolated theropodan phalangeal elements from the Langenberg Quarry.

DfMMh/FV1/19, pedal ungual, in (A) dorsal view, (B) ventral view, (C) left lateral view, (D) right lateral view. DfMMh/FV/343, pedal phalanx, in (E) dorsal view, (F) ventral view, (G) distal view, (H) left lateral view, (I) right lateral view, (J) distal view. DfMMh/FV2/19, pedal phalanx, in (K) dorsal view, (L) ventral view, (M) distal view, (N) left lateral view, (O) right lateral view, (P) distal view. Abbreviations: cg, collateral groove; ext, extensor tubercle; fxf, flexor fossa; fxt, flexor tubercle; lp, ligament pit. All scale bars equal five mm.

Figure 3. Isolated Theropoda axial elements from the Langenberg Quarry.

DfMMh/FV/776, chevron, in (A) anterior view, (B) left lateral view, (C) posterior view, (D) right lateral view, (E) anterodorsal view on proximal articular surface. DfMMh/FV/105, distal caudal vertebra, in (F), ventral view, (G) dorsal view, (H) anterior view, (I) posterior view, (J) left lateral view, (K) right lateral view. Abbreviations: ak, anterior keel; hc, haemal canal; poz, postzygapophysis. Scale bar in A–E equals 20 mm, scale bar in F–K equals 10 mm.

Figure 4. Isolated theropodan fibulae from the Langenberg Quarry.

DfMMh/FV/287, left fibula in (A) anterior view, (B) medial view, (C) proximal view, (D) posterior view, (E) medial view. DfMMh/FV3/19, partial right fibula in (F) anterior view, (G) lateral view, (H) proximal view, (I) posterior view, (J) medial view. Abbreviations: g, groove; mf, medial fossa; pr, posterior ridge; tif, tubercle for the M. iliofibularis. All scale bars equal 20 mm.