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The real lectotype of Kentrosaurus aethiopicus HENNIG, 1915
Abstract
A detailed study of the relevant literature reveals that contra recent use the lectotype of the stegosaur Kentrosaurus aethiopicus Hennig, 1915 is a partial individual from excavation 'St' at Kindope, Tendaguru, Tanzania in the collection of the Museum für Naturkunde Berlin
(MB. R.4800.1-37). This significantly influences the diagnosis of the taxon, defining several characters based on the lectotype instead of referred specimens, notably the sub-vertical neural spines of the medial third of the tail, and the hook-shaped, anteriorly inclined neural spines in the
posterior caudals.
... Kentrosaurus aethiopicus Hennig 1915 is a basal stegosaurid (Mateus et al., 2009;Maidment, 2010) from the Middle and Upper Dinosaur Members (Late Jurassic) of the Tendaguru Formation (Janensch, 1914;Hennig, 1915;Aberhan et al., 2002;Bussert et al., 2009). Up to 30 localities, sometimes consisting of monodominant bone beds, yielded mainly isolated bones and some rare partially associated skeletons (Hennig, 1915(Hennig, , 1916(Hennig, , 1924(Hennig, , 1936Janensch, 1925;Galton, 1982Galton, , 1988Mallison, 2011). The majority of the Kentrosaurus material, including the type specimen (e.g., Janensch, 1914;Maier, 2003;Mallison, 2011) and the femora studied here originate from a monodominant bone bed in the quarry 'St' from the Middle Dinosaur Member. ...
... Up to 30 localities, sometimes consisting of monodominant bone beds, yielded mainly isolated bones and some rare partially associated skeletons (Hennig, 1915(Hennig, , 1916(Hennig, , 1924(Hennig, , 1936Janensch, 1925;Galton, 1982Galton, , 1988Mallison, 2011). The majority of the Kentrosaurus material, including the type specimen (e.g., Janensch, 1914;Maier, 2003;Mallison, 2011) and the femora studied here originate from a monodominant bone bed in the quarry 'St' from the Middle Dinosaur Member. Mainly isolated bones belonging to almost 40 individuals of Kentrosaurus accumulated in this quarry, however, small and delicate elements, such as skull bones and phalanges, are scarce or even absent (Hennig, 1924:200). ...
... Mainly isolated bones belonging to almost 40 individuals of Kentrosaurus accumulated in this quarry, however, small and delicate elements, such as skull bones and phalanges, are scarce or even absent (Hennig, 1924:200). Despite dire losses of Kentrosaurus material during World War II (Maier, 2003;Mallison, 2011), a large number of femora of different sizes, including the sampled ones from the quarry 'St', are stored at the Museum of Natural History (Museum f€ ur Naturkunde) in Berlin, Germany. Janensch (1914) proposed a mass mortality event for this extensive accumulation of mainly isolated to rarely associated bones (Hennig, 1924:200). ...
Using bone histology, a slow growth rate, uncommon for most dinosaurs, has been interpreted for the highly derived stegosaur Stegosaurus (Ornithischia: Thyreophora) and the basal thyreophoran Scutellosaurus. In this study, we examine whether this slow growth rate also occurs in the more basal stegosaur Kentrosaurus from the Tendaguru beds of Tanzania. The bone histology of six femora of Kentrosaurus representing an ontogenetic series from subadult to adult was studied, as well as one scapula. The primary bone is mainly highly vascularized fibro-lamellar bone with some reticular organization of the vascular canals. In addition to LAGs and annuli, distinctive shifts in the pattern of vascularization occur, which have been interpreted as potential growth marks. The variation in the development of growth marks may reflect annual climatic fluctuations. The overall bone depositional rate, and hence growth rate in Kentrosaurus appears to be higher than in Stegosaurus and Scutellosaurus. Considering that Stegosaurus is the larger-sized of the two stegosaurs, this would be contrary to an earlier supposition that small-bodied dinosaurs have slower growth rates than larger ones. Our finding of rapid rates of bone deposition in Kentrosaurus suggests that slow growth rates previously reported in Scutellosaurus and Stegosaurus are not a phylogenetic characteristic of the Thyreophora. Thus, slow growth rates are not plesiomorphic for the Thyreophora. We propose that the slow growth rates documented in the highly derived Stegosaurus could have been secondarily derived or alternatively that Kentrosaurus is the exception having increased growth rates. Anat Rec, 2013. © 2013 Wiley Periodicals, Inc.
... In this context it is important to note that Hennig (1925) and Janensch (1925) as well as Galton (1982) listed the osteoderms in question as parasacral spikes, not parascapular. Mallison (2011c) agreed with this assessment. The bases of all osteoderms show a rugose texture that apparently relates to attachment of tough connective tissues, and a similar mark of identical size to the base of the spikes in question can be found on the dorsal surface of the pelvic shield in all Kentrosaurus hips. ...
... The MfN's Dinosaur Hall displays a mounted skeleton of Kentrosaurus aethiopicus Hennig, 1915, which consists of the lectotype of K. aethiopicus (Hennig, 1925;Janensch, 1925;Mallison, 2011c) and other material. The skeletal elements were described in detail by Hennig (1925), whereas the process of bone selection and mounting was described in Janensch (1925). ...
It has been hypothesized that the pronounced differences of stegosaur
humeral shapes, with large forms having more slender and small forms having
more robust humeri, may be explained by a difference in relative centre of
mass (COM) placement caused by differing distributions of osteoderms. To
test this hypothesis, digital 3-D models of the bones and osteoderms of the
Tanzanian stegosaur Kentrosaurus aethiopicus and of the North
American stegosaur Stegosaurus armatus were used to create
a 3-D computer-aided design life reconstruction. On these models osteoderm
placement was varied drastically, recreating both existing and hypothetical
forms. These models show that COM position varies somewhat with realistic
osteoderm distributions, but insufficiently to explain major differences in
humeral shape. The uniform weight distribution between forelimbs and hindlimbs
found between the two taxa also casts doubt on the hypothesis that
differences in relative COM position caused by other factors than osteoderm
distribution can explain differences in humeral robustness.
... 1). Mallison (2010a) also lists all other material that was present in the MFN collection in fall 2009. The lectotype and most other original material stems from the 'Mittlere Saurierschichten' (Middle Saurian Beds), while manus and some plate/spike material reconstructed in plaster were based on 'Obere Saurierschichten' (Upper Saurian Beds) material (Janensch 1925). ...
... Laser scan based digital files of the plaster replica of the skull, all cervical and dorsals and the sacrum of the MFN mount, in left lateral view in ONP (scale bar 0.5 m) H. Mallison stem from the same individual. In the dorsal series of the MFN mount only three vertebrae stem from the lectotype (Mallison 2010a), and in the neck only one neighbouring pair is from one individual (Janensch 1925). ...
A computer aided design analysis using high-resolution laser scans of the bones of the stegosaur Kentrosaurus aethiopicus Hennig 1915 from the Late Jurassic Tendaguru Formation indicates that in the habitual walking pose the forelimbs were probably held erect, and that strong humeral flexion and abduction mainly occurred in a defensive stance. Rapid gaits with unsupported phases could not be used. The neck allowed sufficient lateral flexion to guarantee good sight in all directions including posteriorly.
The tail covered an arch of roughly 180° and had sufficient range to be used as a weapon. Possibly, the animal could accomplish tail blows against specific targets in sight. Also, a tripodal pose is suggested to have been possible, roughly doubling the maximum vertical feeding height of Kentrosaurus.
Keywords: Stegosauria-Kentrosaurus-Tendaguru Formation-Late Jurassic-Digital skeleton-3D CAD assessment
... These massive spikes with a greatly enlarged base (Fig. 4A), but they are similar to very large based stocky dermal spikes present in several different stegosaurian genera. There is a large based but poorly preserved left stocky spike associated with the partial skeleton of the Atalaia specimen (Fig. 4LUpper Jurassic, Tanzania;heNNiG 1925;JaNeNsch 1925;GaltoN 1982;MallisoN 2010MallisoN , 2011). This is especially true for the first left one (Fig. 4X, number 10 in series; GaltoN 1982: 144, pl. 1, figs. ...
In basal thyreophorans there is no equivalent to the small based slender dermal tail spines of stegosaurs, which differ in several respects from the lateral dorsal spines of nodosaurid ankylosaurs, and large based stocky spikes are restricted to a few genera of stegosaurs. Several isolated spines and spikes from England (Middle and Upper Jurassic), Portugal (Upper Jurassic) and Spain (Lower Cretaceous), previously re-identified as Thyreophora indet., are Stegosauria indet. Where available, cross-sections shows a thick layer of compact bone with a well-defined central canal as in old adult individuals of Stegosaurus (Upper Jurassic, USA) in which, in addition to display, they functioned as weapons. This stronger construction also favored their preservation as isolated bones. It contrasts with a thin layer of compact bone filled with cancellous bone for the spines of adult and younger individuals of Stegosaurus and of ankylosaurs. The preservation of an isolated pair of spines and of spikes indicates that their bases were bound together. Two columnar femora with a finger-like anterior trochanter from England (Middle and Upper Jurassic) are also re-identified as Stegosauria indet., as are the remains of a juvenile individual from Portugal (Upper Jurassic). The autapomorphies of Lori- catosaurus priscus (Nopcsa, 1911) (England, Middle Jurassic: Middle Callovian) include characters observed in the anterior and mid-caudal vertebrae, posterior pubic process and dermal armor (spine plate, small based body spine).
... Parte de este material está hoy extraviado o fue destruido durante la Segunda Guerra Mundial, aunque se conservan moldes de yeso en el Museum für Naturkunde de Berlín, Alemania (véase Maier, 2003). El lectotipo incluye un esqueleto parcial articulado que, junto al paralectotipo, forma parte del esqueleto de Berlín (Mallison, 2011). Kentrosaurus es un estegosaurio de tamaño medio (5 m de longitud) caracterizado por presentar vértebras dorsales cuyo arco neural es dos veces más alto que el centro y con una combinación peculiar de placas y espinas en el dermatoesqueleto (Galton, 1982;Maidment et al., 2008). ...
Thyreophora es un clado de dinosaurios ornitisquios que reúne a estegosaurios, anquilosaurios y formas basales como Scelidosaurus. Su registro fósil se extiende desde el Jurásico Inferior hasta el Cretácico Superior. Muchos de los fósiles de tireóforos descubiertos hasta la fecha provienen de yacimientos situados en el hemisferio norte. No obstante, el registro gondwánico comprende relevantes restos esqueléti- cos y/o icnitas en Sudamérica, África, Madagascar, Australia, Nueva Zelanda y la Antártida. Los tireóforos podrían estar representados en África desde el Jurásico Inferior–Medio. Se ha documentado su presencia en el Jurásico Superior de Tanzania (estegosaurio Kentrosaurus) y en el lí- mite Jurásico–Cretácico de Bolivia (huellas). Durante el Cretácico Temprano, los estegosaurios estuvieron presentes en Sudáfrica (Paranthodon) y la Argentina (forma indeterminada), y los anquilosaurios en Australia (Minmi). Los anquilosaurios también tienen registro en el Cretácico Superior de Sudamérica (restos esqueléticos en la Argentina y huellas en Bolivia), la Antártida (Antarctopelta), Nueva Zelanda y posiblemente Madagascar. La presencia de anquilosaurios y estegosaurios posibles en el Cretácico Superior de la India está sin confirmar. Desde un punto de vista paleobiogeográfico, los tireóforos gondwánicos parecen provenir de diferentes dispersiones desde Laurasia. Los estegosaurios afri- canos serían el testimonio de dos eventos de dispersión ocurridos durante el Jurásico Medio–Tardío. Los anquilosaurios gondwánicos tampoco resultan de una radiación única: Minmi podría representar un linaje relictual establecido en Australia durante el Jurásico antes de la dicotomía Nodosauridae-Ankylosauridae, mientras que los nodosáuridos de la Argentina y la Antártida serían el resultado de una o varias dispersiones desde América del Norte durante el Cretácico Tardío.
... All reviews of the material have concluded that a single species is represented (Hennig, 1915;Galton, 1982b;Maidment et al., 2008). Although associated skeletons of other dinosaurian groups were recovered from the middle and upper saurian beds, only a single associated partial specimen of K. aethiopicus was found, and it is now mounted, preventing it from being included in this study (Mallinson, 2011). No other articulated or associated specimens of K. aethiopicus were recovered and, therefore, any dimorphism identified in femora unfortunately cannot be linked with variation observable in other skeletal elements. ...
Sexual dimorphism, the condition whereby males and females differ from one another physically, is one of the most fundamental aspects of the biology of any animal. However, sexually dimorphic characters can be subtle and are mainly related to soft tissue anatomy. They are, therefore, difficult to identify reliably in the fossil record particularly when dealing with small sample sizes and osteology alone. The first geometric morphometric analysis of dimorphism in a thyreophoran (armored) dinosaur shows that the femora of the stegosaurian dinosaur Kentrosaurus aethiopicus (Upper Jurassic, Tanzania) bear a statistically significant shape difference of the proximal end, which is independent of size and is therefore proposed to be a sexual difference. Although the disarticulated nature of the material means that intraspecific variation in other skeletal elements, such as the enigmatic dermal armor, cannot be identified as sexual dimorphism at this time, this study provides a methodology for further work on articulated stegosaurian specimens and has the potential to reveal additional information regarding the palaeobiology and population dynamics of this poorly understood clade.
... Previous studies either did not detail the range of motion and the kinetics and dynamics of tail motions (e.g., Hennig, 1925;Janensch, 1925), or used much simplified physics-based calculations (e.g., Carpenter et al., 2005;Arbour, 2011), sometimes with significant errors in the equations and measurements. On the basis of high-resolution laser scans of the lectotype (Mallison, 2011) and other well preserved material of the small African stegosaur Kentrosaurus aethiopicus Hennig, 1915 a CAD model was created, based on comparison with extant animals. These comparisons highlighted that most reconstructions suffer from vastly insufficient musculature volumes in the tail. ...
Thyreophora is a taxon of dinosaurs composed of Stegosauria and Ankylosauria, whose members have been known to utilise their tails as powerful defensive weapons. Remains of these dinosaurs are scarce; the Portuguese taxon, Miragaia longicollum, known from three individuals, provides precious pieces of information on the anatomy of these rare animals. This study estimates the stress resistance of a stegosaurian tail and uses Multi-Body Dynamics Analysis (MBDA) to properly simulate the movements of the tail of M. longicollum. The results show that the tail of M. longicollum can achieve high speeds and generate significant pressures, akin to those observed in other tyreophoran dinosaurs. Such high speeds would potentially generate powerful strikes and would inflict injuries on predators. However, the caudal spines of M. longicollum, despite being larger than those of Stegosaurus stenops, have worse stress-bearing performances than those of S. stenops, due to their different morphology. Investigating the complex biomechanics governing the tail of a dinosaur, such as M. longicollum, can have significant implications across various disciplines. Investigating biomechanics in extinct species offers valuable insights into comparative anatomy and physiology, facilitating connections between ancient and contemporary life forms. Palaeontologists and evolutionary biologists might use this information to better comprehend the dinosaur movement, which would advance our understanding of ancient ecosystems and have an impact on how we interpret the behaviour of contemporary animals. The knowledge obtained from such study might provide useful biomimicry lessons for robotics engineers, serving as inspiration for the creation of more adaptable and agile robotic systems.
Levantamento das ocorrências dos dinossauros ornitísquios gondwânicos e as condições ambientais que implicaram na distribuição do grupo no supercontinente.
What dinosaurs really looked like is (and has always been) of great interest to most people, ever since the first skeletons were found. Reconstruction methods changed over time, and the better the understanding of the anatomy of these animals is, the better are usually the reconstructions. If the body mass it known, it is possible to derive many physiological data, which in turn improve our understanding of the way of life of these extinct animals. A simple method of estimating the weights of dinosaurs is by reconstructing the body surface area, calculating the body volume, and estimating the body mass for all body parts using specific weights based on analogies to extant animals. The developmental path of a reconstruction, from a mounted skeleton to a scientific realistic looking digital dinosaur, will be detailed in this chapter. Initially, a mounted skeleton is laser scanned to derive a non-scaled 3D point cloud. The second step is to reconstruct the external shape of the living animal, and thus the body surface area, using special software. This can be done by using non-uniform rational B-splines (NURBS). Next, the modeled dinosaur should be assessed for plausibility by physiologists, to check the fit of the interior organs. When necessary the model must be adapted. This can be an iterative process, and sometimes many changes must be realized to arrive at an acceptable result. This method results in editable and decidedly more accurate models of dinosaurs, which deliver significantly better data on physiological parameters than classic methods.
The plated dinosaur Stegosaurus longispinus came from the Morrison Formation (Upper Jurassic) near Alcova, Wyoming, USA. Only the femur and plaster casts of the posterior pair of long dermal tail spines survived destructive water damage in the 1920s. This surviving material and archival photographs showing the bones in the quarry and as exhibited allow us to expand the original description. S. longispinus Gilmore, 1914 is made the type species of Alcovasaurus n. gen. as A. longispinus (Gilmore, 1914). Autapomorphies include the continuation of transverse processes to the distal caudal vertebrae; distal caudal centra anteroposteriorly short so height exceeds length; both distal dermal spine pairs with a very long slender shaft at ~90% of femoral length, and posterior pair widest at 25% of length. Natronasaurus longispinus was proposed by Ulansky (2014) for S. longispinus. However this failed to meet the requirements of the International Code of Zoological Nomenclature, as is also true for 17 other names proposed for basal thyreophorans and stegosaurs.
The first partial skeleton of a stegosaurian dinosaur was discovered in a brick pit in Swindon, UK in 1874. Since then, numerous
stegosaurian remains have been discovered from Europe, North America, Africa and Asia, and continue to be discovered regularly.
Stegosaurs are known from the Middle Jurassic to the Early Cretaceous; no definitive evidence of the clade is known from younger
deposits. New discoveries are improving our understanding of stegosaur biology and showing that stegosaurs were more morphologically
diverse than was previously realized. A new phylogeny, which includes all valid stegosaurian taxa, largely agrees with previous
studies and shows the European Dacentrurinae was sister taxon to Stegosaurus. Poor resolution at the base of Stegosauria is probably due to the fragmentary nature of many of the Chinese taxa.
KeywordsDinosauria-Ornithischia-Stegosauria-Phylogeny
Stegosauria is a clade of ornithischian dinosaurs characterised by a bizarre array of dermal armour extending, in two parasagittal rows, from the cervical region to the end of the tail. Although Stegosaurus is one of the most familiar of all dinosaurs, little is known regarding the evolutionary history of this clade.Alpha‐level taxonomic revision of all proposed stegosaur taxa shows that 11 species of stego‐saur can be regarded as valid on the basis of autapomorphies. These are: Dacentrurus armatus and Loricatosaurus priscus (gen. nov.) from Europe; Kentrosaurus aethiopicus and Paranthodon afric‐anus from Africa; Tuojiangosaurus multispinus, Chungkingosaurus jiangbeiensis, Huayangosaurus taibaii, Gigantspinosaurus sichuanensis and Stegosaurus homheni (comb. nov.) from China; and Stegosaurus mjosi (comb. nov.) and Stegosaurus armatus from North America.A cladistic analysis of Stegosauria (the first to be based upon direct observation of all relevant specimens) is presented, which indicates that Tuojiangosaurus, Loricatosaurus and Paranthodon are sister taxa to Stegosaurus. Stegosaurinae can be defined as all stegosaurs more closely related to Stegosaurus than to Dacentrurus; Stegosauridae is defined as all stegosaurs more closely related to Stegosaurus than to Huayangosaurus; and Huayangosauridae can be defined as all stegosaurs more closely related to Huayangosaurus than to Stegosaurus. This study is also the first phylogenetic analysis to include Gigantspinosaurus, which is recovered as the most basal stegosaur.