The Family Tree of the Pterosauria 7 – The Rise of Germanodactylus

We just looked at the smallest of all pterosaurs, B St 1967 I 276, tiny No. 6 from the Wellnhofer (1970) catalog. Descendants grew larger quickly with a larger, sharper rostrum and mandible tipped by a single tooth. Thus began the rise of Germanodactylus and all of its many, varied and crested progeny.

basal germanodactylids

Figure 1. Basal Germanodactylia. Three taxa preceding Germanodactylus rhamphastinus: No. 6, No. 12 and No. 23 all to scale. This rapid size increase succeeded a size shrinkage culminating with No. 6, the smallest of all pterosaurs.

No. 12
Formerly considered a species of Pterodactylus, No. 12 needs a new name because here it nested between two predecessors to Germanodactylus. Twice as tall as No. 6, No. 12 had a much longer and sharper rostrum, the hallmark of the new clade. Like all germanodactylia, a procumbent tooth further sharpened the jaw tips and palatal extensions of the maxilla reinforced them. The antorbital fenestra was only half the rostral length. The teeth were larger. The lacrimal was enlarged. The quadrate angle was elevated. The postorbital was raised. The cervicals were elongated. The caudals were robust. The sternum had sharp posterior corners. The scapula was curved. The ventral coracoid was expanded. The humerus was relatively shorter. The ulna was twice as long as the humerus. The ischium was perforated. The metatarsus was appressed. Pedal 4.4 was shorter.

No. 23
Formerly considered the holotype of the species. Pterodactylus kochi (Wagner 1837 Ornithocephalus? kochi von Meyer 1859), B St ASXIX 3 (plate) SMF No. R 404 (counterplate), No. 23 of Wellnhofer 1970) also needs a new name. It was 2.5 times taller than No. 12. Distinct from No. 12, the skull of No. 23 was sharper, the jugal was deeper, the teeth were larger and the mandible was deeper. The torso was deeper. The dorsal ribs were more robust. The sacrals were relatively larger. Manual 4.3 approaches the elbow. The wing, when folded, barely reaches the top of the cervicals. The pelvis was relatively larger.

Germanodactylus and kin

Figure 2. Click to enlarge. Germanodactylus and kin.

Germanodactylus rhamphastinus
Germanodactylus rhamphastinus (Wagner 1851 B St AS I 745, No. 64 of Wellnhofer 1970) was the first of the raven-sized germanodactylids. No. 64 was derived from No. 23 and phylogenetically preceded Eosipterus and JME Moe 12. Distinct from No. 23, the skull of No. 64 was deeper anteriorly and crested posteriorly. The orbit was smaller with a V-shaped ventral margin. The teeth were larger and narrower. The jugal was narrower and deeper. The cervicals were longer and decreased in size cranially. The torso was reduced. The caudals were longer as a set, but most individual caudals remained short. The deltopectoral crest did not lean medially. The humerus was straight. The metacarpus was relatively longer. Fingers I-III were more robust and the unguals were larger. Manual 4.2 extended just to the elbow. The ischium was bifurcated. The prepubis was L-shaped. Pedal digit I was shorter. The unguals were smaller.

Same genus? Or not the same genus?
Germanodactylus cristatus B St 1892 IV 1 (Pterodactylus kochi Plieninger 1901, Germanodactylus cristatus Wiman 1925, No. 61 of Wellnhofer 1970) was the type specimen for this genus. G. rhamphastinus was referred to the genus. There are only two specimens that nest between the holotype and the first referred specimen, so the morphological disparity, while great, is no more than is found in various specimens attributed to Campylognathoides, Rhamphorhynchus, Pterodactylus and Pteranodon. The trouble comes later with an undescribed specimen referred to Germanodactylus cristatus (SMNK-PAL 6592). At least two unnamed transitional taxa, plus the much larger Elanodactylusseparate it from the holotype.

Next time we’ll examine the wide variety within the genus Germanodactylus.

As always, I encourage readers to see specimens, make observations and come to your own conclusions. Test. Test. And test again.

Evidence and support in the form of nexus, pdf and jpeg files will be sent to all who request additional data.

References:
von Huene F 1951. Zwei ausgezeichnet erhaltene Exemplare von Pterodactylus im Natur-Museum Senckenberg. Senckenbergiana 32: 1–7.
von Meyer CEH 1859.
 Zur Fauna der Vorwelt. Vierte Abt.: Reptilien aus dem lithographischen Schiefer des Jura in Deutschland und Frankreich.1. Lieferung: 1–84 & pls, 1859 and 2. Lieferung: 85–114 & pls, 1860. Frankfurt am Main: H. Keller. [pp. 7–90, 141–144 & pls 1–10.]
Wagner JA 1851. Beschreibung einer neuen Art von Ornithocephalus nebst kritischer Vergleichung der in derk. Paläontologischen Sammlung zu München aufgestellten Arten aus dieser Gattung. Akademie der Wissenschaften Mathematischen-physikalischen Klasse6: 127–192 & pls 5–6.
Wellnhofer P 1970. Die Pterodactyloidea (Pterosauria) der Oberjura-Plattenkalke Süddeutschlands. Abhandlungen der Bayerischen Akademie der Wissenschaften, N.F., Munich 141: 1-133.

wiki/Germanodactylus

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s