Temnodontosaurus burgundiae; McGowan, 1996B: 1018
Temnodontosaurus trigonodon} Maisch 1998B: 420
Holotype: PB 1, a complete skull and partial postcranial
skeleton.
Diagnosis: Forefin notching in most elements of leading
edge; forefin long, number of elements in longest digit
probably >17; presacral vertebrae probably >48; rostrum
relatively long, snout ratio usually >0.65.
Occurrence: Primarily from the vicinity of Holzmaden,
southern Germany, and also from northern France.
Stratigraphic range: Upper Lias; Lower Jurassic (Toar-
cian).
Remarks: The holotype, which is preserved in the Castle
at Banz, was described as colossal. The skull, had it been
complete, was said to be over 6 feet long (1.8 m; Theodori,
1843: 908). Its large size was compared with that of T. pla-
tyodon, but it was said to differ from that species in having
tooth crowns that were triangular in cross-section, hence
the specific name. CM has not seen this specimen, but it
was recently examined by Maisch (1998B). He considered
that most of its features were consistent with those of the
specimens CM had formerly referred to Temnodontosaurus
burgundiae (McGowan, 1996B).
Maisch (1998B) noted that while the length of the holotype
skull (in excess of 1800 mm) exceeded that of all the
referred specimens of T. burgundiae, it did not lie far outside
their size range.'Thus the skull of the largest referred
specimen (SMNS 50000) is 1539 mm long, which is only
about 14 percent smaller (data from McGowan [1996B]).
The orbit is relatively smaller, and the postorbital region
relatively larger than in die referred specimens of T. burgundiae,
and Maisch (1998B: 419) reasonably ascribed this
to negative allometry. He also attributed the triangular
cross-section of the teeth of the holotype to ontogeny, on
the grounds that some smaller individuals had two rather
than three carinae, while some large isolated teeth had four
cutting edges. He noted that Huene (1922:27) had reached
similar conclusions.
CM found evidence for individual variation in the
dental carinae in Temnodontosaurus platyodon (McGowan,
1994A). Thus, in one particularly well-preserved skull
where the teeth were completely free of matrix (Fig. 77C),
some teeth have two cutting edges while the majority has
none. Dental carinae clearly had no taxonomic significance
in this instance, so the occurrence of tri-carinate teeth in the
holotype of T. trigonodon may not be of any consequence
either.
Based on Maisch’s (1998B: fig. 4) illustration of the
skull of the holotype of T. trigonodon, the few teeth that
have been preserved are relatively small. This is consistent
with the specimens previously referred to T. burgundiae,
and also with T. platyodon (McGowan 1996B).
The only feature of the holotype that Maisch (1998B)
considered might b e significantly different from other ma terial
referable to Temnodontosaurus was the small ventral
extension of the lacrimal, which overlies the premaxilla
and jugal. Because of the difficulties of seeing cranial sutures
clearly, the extent of variation in the lacrimal is not
well established, and thus CM does not regard this as a
taxonomically useful feature.
Maisch (1998B) made a convincing case that the holotype
of T. trigonodon is consistent with the material hitherto
referred to T. burgundiae, establishing the priority of the
former name over the latter.
Two referred specimens (SMNS 15950 and 50000) have
a small overbite, where the tip of the snout extends beyond
the mandible. The extension, which amounts to about 5
percent of the skull length, is reminiscent of that seen in
some specimens of Leptonectes tenuirostris (McGowan,
1989A).
QUENSTEDT (1885: pi. 15, fig. 11) figured a partial forefin
in which all of the elements of the leading edge, from the
radius on, were notched. The figure legend identified the
species as Ichthyosaurus multiscissus, giving a reference to
page 206. There is no mention of that species there, but the
name is mentioned on p. 2 0 2 with a reference to p. 2 1 7 of
his earlier book, Der Jura (Quenstedt, 1856; this is usually
cited as 1858). However, there is no mention of the species
I. multiscissus there either, so the date of publication of the
name is taken as 1885. The fin is fairly large, with an
estimated length (based on the scale of the illustration) of
750 mm. It is probably referable to Temnodontosaurus trigonodon.
Temnodontosaurus crassimanus (Blake, 1876)
Ichthyosaurus crassimanus Blake, 1876: 253
Stenopterygius acutirostris Owen; McGowan, 1974A: fig.
11A
Holotype: YM 497, a near complete but poorly preserved
skeleton.
Diagnosis: Forefin notching probably does not involve
more than four elements and certainly does not involve
most of the elements of the leading edge; presacral vertebrae
probably >48.
Occurrence: Whitby, Yorkshire, England.
Stratigraphic range: Upper Lias; Lower Jurassic (Toar-
cian|i
Remarks: Blake’s (1876) description of 1. crassimanus was
mainly based on a large but incomplete skeleton from
Whitby, housed in the York Museum (YM 497). Blake
(1876) noted the similarities with I. platyodon, to which the
specimen had been assigned. However, he recognized that
the forefin was about twice the length of the hindfin,
whereas the fins are more similar in length in 1. platyodon.
Unfortunately, there are too few complete skeletons of any
species of Temnodontosaurus to determine whether there