from the upper Sticky Keep Formation (Upper Saurian
Level) of Hamiltonsberg, Spitsbergen (Svalbard) (PMU
unnumbered), collected in 1913, that would be almost indistinguishable
from UCMP 9 873 if it were not for its pale
color and broken head. Therefore, there is a possibility that
UCMP 9873, together with this unnumbered specimen at
PMU, may represent young individuals of M. nordenskioe-
Idii. Also, as W iman (1916) pointed out, the humerus may
belong to M. fraasi.
Ekbainacanthus tschemyschewi Y akowlew, 1902
Y akowlew (1902: 180) erected this species upon a collection
of several bones that he thought were derived from a
single individual. The discoverer of the specimen, T. Tscher-
nyschew, assured Yakowlew of the association of the specimens
in the field. The bones included an ischium, a tooth
fragment, and several vertebrae and ribs (the supposed
scapula is most likely a rib head), and occurred in a layer
above the upper Sticky Keep Formation (Upper Saurian
Niveau) of Spitsbergen, Svalbard (Wiman, 1 9 1 0 :1 2 8 ). This
probably places the horizon near the Ladinian-Camian
boundary. W iman (1910) was not convinced by the suggested
ichthyosaurian affinities of the specimens: he could
not eliminate the possibility of their having been derived
from a labyrinthodont. Judging from the published figures
(Yakowlew, 1902: pi. 3 ), the tooth fragment seems to be
ichthyosaurian in having plicidentine without secondary
enfolding (Schultze, 1970), and the ischium is similar to
the ones known for basal merriamosaurians. The specimens
are non-diagnostic for erection of a species, and
hence the name Ekbainacanthus tschemyschewi is considered
a nomen dubium.
Ichthyosaurus aduncus Quenstedt, 1885
This species was erected upon an immature skeleton from
Holzmaden, Germany in which the tip of the rostrum was
upturned. Although Quenstedt (1885: 2 0 5 , pi. 16, fig. 27)
recognized this was a malformation, he still formally proposed
the name. As the individual is immature it cannot be
identified to species.
Ichthyosaurus aequalis Phillips, 1871
Based on a single caudal vertebra, from the Kimmeridge
Clay (Upper Jurassic: Kimmeridgian) of Shotover, Oxfordshire,
England. Said to be unusual for the “position of the
single prominent excavated apophysis” (Phillips, 1871:
339). The material is indeterminate.
Ichthyosaurus amalthei Quenstedt, 1856
The 18 caudal vertebrae upon which this species was established
were said to be unusual for the flatness between
their “articular eminences” (Quenstedt, 1856: 2 17). The
material is clearly inadequate for the erection of a species.
Ichthyosaurus arietis F raas, 1891
Fraas (1 8 9 1 :4 1 , pi. 3 , figs 17-18) referred to some vertebrae,
characterized by their large size (110-125 m m diameter),
under this name. Such material is too inadequate to be
assigned to species, but can probably be referred to the
genus Temnodontosaurus:
Ichthyosaurus bambergensis Bauer, 1901
The holotype is an incomplete and partially scattered skeleton,
from the Upper Lias of Bavaria, Germany, which has
lost most of its teeth, though a few are preserved. Its
principal distinguishing feature is its hatchet-shaped coracoid
(Bauer, 1 9 0 1 :2 0 , pi. 1, fig. 5). It is unclear whether this
is a natural or an erosional feature, but it may well be the
latter. This modest-sized skeleton (1.64 m long) is probably
referable to Stenopterygius; however, in the absence of a
pelvic girdle this cannot be confirmed. The specimen is
probably too poorly preserved to be identifiable beyond
the generic level.
Ichthyosaurus biscissus Wurstemberger, 1876
The 1.36-m-long skeleton upon which Wurstemberger
(1876: 225) erected this species was said to have no special
characteristics. It was found in the same Upper Liassic
horizon as the holotype of Ichthyosaurus aScissus, and, like
that specimen, it was probably destroyed during World
War II. The original material was seemingly without any
distinguishing features, and has probably been lost.
Ichthyosaurus bodenbenderi Dames, 1893
Dames (1893: 2 3 ) erected this species on a series of five
vertebrae and rib fragments, from the Upper Jurassic
(Kimmeridgian) of La Cienegita near Malargiie, Mendoza,
Argentina. This material is indeterminate.
Ichthyosaurus brachyspondylus Owen, 1881
Trautschold (1876: 87, pi. 4, fig. 3a,b) mentioned and
figured this species, which he attributed to Owen. Owen
(1881: 127, pi. 33, figs. 3-6) described an unremarkable
vertebral centrum, presumably from the Lower Lias, that
he considered was shorter, relative to its diameter, than
any other he had seen. The material is indeterminate.
Ichthyosaurus brunsvicensis Broili, 1909
Broili (1909: 296, figs. .1-2, pi. 27) figured and described
some individual cranial elements, including a basisphe-
noid and basioccipital, from the Lower Cretaceous of
northern Germany. All that can be said of Broili’s (1909)
material is that it belongs to Platypterygius. His figure of the
basioccipital has been redrawn here as exemplary of the
genus (Fig. 38).
Ichthyosaurus californicus Camp, 1942
This species was erected on a rostral fragment from the
Franciscan Group of California (Camp, 1942, p. 367), which
appears to be Late Jurassic in age. This material is not
diagnostic.
Ichthyosaurus carinatus Sauvage, 1876
The very brief description of this material, from the uppermost
Triassic (Rhaetian) of France, made reference to features
of the vertebral column. This material is not diagnostic.
Ichthyosaurus ceramensis Martin, 1888
This species, from the south coast of Ceram, Indonesia,
was erected upon a portion of rostrum of a large individual
(Martin, 1888: 74, pi. 10). The horizon was said to be
equivalent to the Chalk Marl and Upper Greensand of
England, and may therefore be taken as Early Cretaceous.
The material is referable to Platypterygius.
Ichthyosaurus coniformis Harlan, 1824b
This Early Jurassic species was erected upon a fragment of
“dental bone ... containing six teeth . . . ” (Harlan, 1824B:
338), said to be from Bath or Bristol. The species was
largely characterized by the form of the teeth (Harlan,
1824B: 339), but is not based on diagnostic features.
Ichthyosaurus crassicostatus Theodori, 1854
The type specimen, a large scattered skeleton, comprised
parts of the mandible, some scleral plates, an articulated
portion of the vertebral column with attached ribs, both
coracoids, an incomplete scapula, scattered vertebrae, rib
fragments, several fin elements and many isolated teeth.
The species was named for the thickness of the ribs, and
the vertebrae were said to be relatively deeper than those
of other ichthyosaurs from the Upper Lias of Banz, Germany.
Huene (1922: 5 1) believed this specimen, which, he
noted, had been identified by Fraas (1891), was referable
to Eurhinosaurus longirostris. He should therefore have syn-
onymized the name I. crassicostatus with E. longirostris.
Instead, he chose to conserve the name. The holotype,
which is too incomplete to be diagnostic, may well represent
E. longirostris.
Ichthyosaurus cuvieri Valenciennes, 1861A
This species, from the Kimmeridge Clay of Normandy,
was erected upon an incomplete, damaged skull, exposed
from the right side. Valenciennes (1861A) did not illustrate
the material, but it was subsequently figured by Len-
NIER (1870: pi. 6, figs. 1-5). The type material was destroyed
during World War II, but a plaster cast of the skull is
preserved in Paris (MNHN 245-1870; Bardet et al., 1997).
Distinguishing features are the large orbit and scleral ring,
and the large, but sparse teeth. The skull was so incompletely
preserved that its affinities cannot be established
with certainty. The large size of the orbit is suggestive of
Ophthalmosaurus, and this assignment is supported by the
sparsely distributed teeth, which are restricted to the anterior
segment of the rostrum. Bardet et al. (1997) compared
the general robustness of the skull and teeth with that of
Brachypterygius, concluding that this is where the species
should be referred. However, if comparisons are made
between the skulls of Brachypterygius (McGowan, 1976:
fig. 1), Ophthalmosaurus (Kirton, 1983: fig. 14) and the holotype
of Ichthyosaurus cuvieri (Lennier, 1870: pi. 6, fig. 1), it
is apparent that the teeth are relatively much larger and
more robust in Brachypterygius than in either Ophthalmosaurus
or Ichthyosaurus cuvieri. However, the latter differs
from Ophthalmosaurus in having a relatively small scleral
ring compared with the orbital diameter, and in this respect
it is more like the condition in Brachypterygius. It is
unfortunate that little remained of the basioccipital because
if this element had been well preserved this would
probably have resolved the taxonomic issue. As the type
material has been destroyed there is no possibility of adding
any new data to our incomplete knowledge of this
species, which is accordingly treated as a nomen dubium.
Ichthyosaurus dilatatus Phillips, 1871
A considerable number of dorsal and caudal vertebrae
were said to have a relatively greater breadth than in
Ichthyosaurus trigonus, and I. dilatatus was erected for their
reception (Phillips, 1871:339). This material, from the Kimmeridge
Clay (Upper Jurassic: Kimmeridgian), is indeterminate.
Ichthyosaurus franciscanus C amp, 1942
Like I. californicus, Camp (1942: 3 6 2 ) erected this species
upon a fragment of rostrum from the Franciscan Group of
California, which is apparently Late Jurassic in age. The
material is indeterminate.
Ichthyosaurus hexagonus Theodori, 1854
Theodori (1854: 55, pi. 4, figs. 8, 9, 15, 46) described a
scattered, partial skeleton comprising large pieces of the
mandible, part of the postorbital region, an almost complete
jugal, 17 vertebrae of varying sizes, many rib and
tooth fragments, a scapula, humerus, and many fin elements,
from the Upper Lias of Banz, Germany. The diagnostic
feature, reflected in the specific name, was said to be
the hexagonal shape of the vertebrae, when viewed anteriorly,
which according to Theodori (1854) was not preser-
vational. Bauer (1901:13) contended that the anterior profile
of an ichthyosaurian centrum was determined by the
rib facets. As these are located anteriorly, centra appear