A new Rhamphorhynchus from England

Most
Rhamphorhynchus specimens come from the Solnhofen limestones of southern Germany. A few questionable scraps have been reported from elsewhere around the world.

Figure 1. The MJML-K 1597100 specimen of Rhamphorhynchus described by O'Sullivan and Martill 2015. Watch out for those scale bars or your reconstruction will be odd. Also note the presence of a manual digit 5 in the traditional place, size and shape, pretty much fused to metacarpal 4. Pretty clearly shown  here. Click to enlarge.

Figure 1. The MJML-K 1597100 specimen of Rhamphorhynchus described by O’Sullivan and Martill 2015. Watch out for those scale bars or your reconstruction will be odd. Also note the presence of a manual digit 5 in the traditional place, size and shape, pretty much fused to metacarpal 4. Pretty clearly shown  here. Click to enlarge.

A recent paper
by O’Sullivan and Martill (2015) accurately reports the presence of a Rhamphorhynchus wing from English deposits. A new species R. etchesi is proposed and it appears to be valid (if you’re a splitter).

As reported earlier,
I have yet to find two Rhamphorhynchus specimens that were identical to one another. Each one (so far) has been distinct. Only two specimens, a mid-sized juvenile and one of the giant adults (Fig. 3), had identical scores, as reported earlier here. These two were thus considered conspecific and a juvenile/adult pairing.

The tiny Rhamphs
The O’Sullivan and Martill study also regards Qinglongopterus and Bellubrunnus (misspelled “Bellebrunnus” in the paper) as similar enough to Rhamphorhynchus to be considered junior synonyms. That hypothesis was also presented earlier here and here and was demonstrated several years ago by the large pterosaur tree. A manuscript with the same conclusion was rejected earlier this year. In any case, this conclusion by O’Sullivan and Martill is validation for the DGS technique and the recovered tree topology.

Figure 2. The x specimen of Rhamphorhynchus, n52 in the Wellnhofer catalog, is a close match to the new English Rhamphorhynchus. The radius is more slender and manual4.1 is shorter than m4.2 in the English specimen.

Figure 2. The B St 1929 I 69 specimen of Rhamphorhynchus, n52 in the Wellnhofer catalog, is a close match to the new English Rhamphorhynchus. The radius is more slender and manual 4.1 is shorter than m4.2 in the English specimen.

The English Rhamphorhynchus
wing is a pretty big one (Fig. 3) with distinct proportions that nest it with the B St 1929 I 69 specimen of Rhamphorhynchus n52 specimen (in the Wellnhofer 1975 catalog). However, the radius is narrower and manual 4.1 is shorter than 4.2. These traits make it distinct from the n52 specimen. However these traits are not unique. The related GPIH MYE 13 specimen (Fig. 3, lower right) ) also has a shorter m4.1 than m4.2 — but it has a humerus with a different shape.

Figure 3. Bennett 1975 determined that all these Rhamphorhynchus specimens were conspecific and that all differences could be attributed to ontogeny, otherwise known as growth to maturity and old age. Thus only the two largest specimens were adults. O'Sullivan and Martill took the brave step of erecting a new species. The n52 specimen is at the lower right. Click to enlarge.

Figure 3. Bennett 1975 determined that all these Rhamphorhynchus specimens were conspecific and that all differences could be attributed to ontogeny, otherwise known as growth to maturity and old age. Thus only the two largest specimens were adults. O’Sullivan and Martill took the brave step of erecting a new species. The n52 specimen is at the lower right. Th new English wing is at the top. Click to enlarge.

From the O’Sullivan and Martill abstract: “The second pterosaur genus to be established, Rhamphorhynchus von Meyer, 1847, has historically been used as a wastebasket material. Several species have been erected for fossils found in Europe and Africa, the majority of which are based on non-diagnostic material. Following Bennett’s (1996) review of its taxonomy, Rhamphorhynchus is generally regarded as a monospecific taxon restricted to the Late Kimmeridgian and Tithonian of Southern Germany. Here we describe a disarticulated but complete right pterosaur wing, MJML K-1597 from the Kimmeridge Clay Formation of England. Based on a combination of morphology and statistical analysis, MJML K-1597 can safely be referred to Rhamphorhynchus, making it the first diagnostic Rhamphorhynchus specimen from outside of Germany. Furthermore, based  on the unique length ratio between wing phalanx 1 and wing phalanx 2, MJML K-1597 can be referred to a new species of Rhamphorhynchus.”

Unfortunately, there is no link at present for Supplementary Data
in the O’Sullivan and Martill paper, or the url to which the current Supp Data links, so several references to SuppData await that link. The authors report they included 54 Rhamphorhynchus specimens in their study, but did not perform a cladistic analysis. Rather they employed several bivariate analyses which compared the ratios of one bone with another that preceded it. The analyses were performed on the generic level.

I was able
to nest the English Rhamphorhynchus on the specimen level using cladistic analysis without loss of resolution. I wish Rhamphorhynchus workers would at least try this sometime, and not reject papers that do this successfully based on outmoded paradigms.

Finally,
whenever I find a manual digit 5 on a pterosaur, I like to point it out. MJML K-1507 provides a great example (Fig. 1) on a pristine metacarpal 4. In this anterior view, imagine the large extensor tendon running like a strap across the face of it with digits 1-3 in a horizontal plane extending toward the viewer below that strap, essentially between digits 1-3 and 5, which is where you should expect to find the extensor tendon for digit 4.

References
Bennett SC 1995. A statistical study of Rhamphorhynchus from the Solnhofen Limestone of Germany: Year-classes of a single large species. Journal of Paleontology 69:569-580.
O’Sullivan M and Martill DM 2015.
Evidence for the presence of Rhamphorhynchus (Pterosauria: Rhamphorhynchidae) in the Kimmeridge Clay of the UK. Proceedings of the Geologists’ Association. G Model PGEOLA-417; 12 pp.
Wellnhofer P 1975a-c. Teil I. Die Rhamphorhynchoidea (Pterosauria) der Oberjura-Plattenkalke Süddeutschlands. Allgemeine Skelettmorphologie. Paleontographica A 148: 1-33. Teil II. Systematische Beschreibung. Paleontographica A 148: 132-186. Teil III. Paläokolgie und Stammesgeschichte. Palaeontographica 149: 1-30.

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