Taxonomic problems? Go back to the holotype.

Sometimes taxa are mislabeled.
Such is the case with Pholidophorus? radians (Figs. 1–3), a ‘herring-like’ Jurassic (Solnhofen Fm.) fish with ganoid scales, tiny fins and a large forked tail. This specimen (Fig. 1) was identified as Pholidophorus in The Rise of Fishes (Long 1995) and at the Wikipedia entry for Pholidophorus.

Figure 3. Pholidophorus in situ and two skulls attributed to this genus. Compare the one on the left to figure 2. No tested fish in the LRT is closer to Robustichthys than Pholidophorus.

Figure 1. Pholidophorus in situ and two skulls attributed to this genus from Long 1995. Neither diagram matches this specimen, despite overall similarities.

The images in the diagrams above
(Fig. 1) are indeed variations on Pholidophorus (Fig. 4). However, the specimens in the photographs (Figs. 1–3) nest with Elops, the ladyfish (or tenpounder) in the large reptile tree (LRT, 1668+ taxa) on the other branch of bony fish.

Figure 2. Another specimen of Pholidophorus? radians

Figure 2. Another specimen attributed to Pholidophorus? radians

Figure 3. DGS tracing of Pholidophorus? radians along with a reconstruction moving the crushed bones to their invivo positions.

Figure 3. DGS tracing of Pholidophorus? radians along with a reconstruction moving the crushed bones to their invivo positions.

Yesterday
I found the Pholidophorus latiusculus holotype in the literature (Arratia 2013; Late Triassic; Fig. 4). The LRT recovered it apart from the Solnhofen (Late Jurassic) specimen identified as Pholidophorus in Long 1995 and Wikipedia.

The Late Triassic holotype of Pholidophorus
nests with Osteoglossum, the extant arrowana of South America and spiny-finned Bonnerichthys, from the Niobrara Sea of the Cretaceous. All likely had their genesis in the Late Silurian based on their close-to-the-base phylogenetic node.

Figure 4. Pholidophorus holotype from Arratia 2013, overlay drawing from Agassiz 1845.

Figure 4. Pholidophorus holotype from Arratia 2013, overlay drawing from Agassiz 1832.

It is easy to see how later specimens
were allied with the holotype, but this turns out to be yet another case of convergence. A wide gamut phylogenetic analysis that minimizes taxon exclusion minimizes phylogenetic errors like this one. Earlier I made the mistake of combining the data from the diagram (Fig. 1) and the photo (Fig. 2) creating a chimaera. Best to just find the holotype and work from that.


References
Agassiz L 1832. Untersuchungen über die fossilen Fische der Lias-Formation. Jahrbuch für Mineralogie, Geognosie, Geologie und Petrefaktenkunde, 3, 139–149.
Arratia G 2013. Morphology, taxonomy, and phylogeny of Triassic pholidophorid fishes (Acinopterygii, Teleostei). Journal of Vertebrate Paleontology 33:sup1:1–138.
Sallan LC 2012. Tetrapod-like axial regionalization in an early ray-finned fish. Proceedings of the Royal Society B 279:3264–3271.

wiki/Pholidophorus

Elgin and Hone 2020 document two large Solnhofen pterosaur wings

Two large, disassociated,
but strongly similar Solnhofen pterosaur wings, SMNK 6990 (Fig. 1) and MB.R.559.1 (Fig. 2) were described in detail by Elgin and Hone 2020. Unfortunately they did so without a phylogenetic analysis and therefore presented no firm hypothesis of interrelationships.

Figure 1. The SMNK 6990 wing from Elgin and Hone 2020. Contrast was raised from the original photo. Metacarpal 1 is actually mc3. Reconstruction in figure 3.

Figure 1. The SMNK 6990 wing from Elgin and Hone 2020. Contrast was raised from the original photo. Metacarpal 1 is actually mc3. Reconstruction in figure 3.

In the SMNK 6990 specimen
(Fig. 1) Elgin and Hone 2020 mistakenly flipped metacarpals 1-3  then wondered why 2 and 3 were reduced.

In the MBR.5991.1 specimen
Elgin and Hone 2020 overlooked the three free fingers.

Figure 2. MB.R.5991.1 specimen as originally published, higher contrast image and color tracing including three overlooked free fingers and a radius.

Figure 2. MB.R.5991.1 specimen as originally published, then a higher contrast image and color tracing including three overlooked free fingers and a radius.

In their conclusion,
Elgin and Hone first guessed, then gave up trying to figure out what sort of wings these were when they reported, “a placement within either the Ctenochasmatoidea or Dsungaripteridae appears most likely… further differentiation is impossible.”

Figure 3. Luchibang, Pterodactylus longicollum and the two new Solnhofen wings to scale.

Figure 3. Luchibang, Pterodactylus longicollum and the two new Solnhofen wings to scale. The latter two are nearly identical.

In counterpoint,
testing against all 242 taxa 
already in the large pterosaur tree (LPT, where nothing is impossible) both new Solnhofen wing specimens nested with the largest pterodactylids, including, ironically, Luchibang (Fig. 3), which just this month Dr. Hone mistook for an ornithocheirid with weird proportions.

Alas, and with regret,
these two authors have a long history of making similar mistakes and overlooking details despite having firsthand access. Those low batting averages were covered earlier herehere, here, here, here and here. Not sure why referees keep accepting such work for publication. In the end it just has to be cleaned up.

Contra the authors’ title,
the traditional clade ‘Pterodactyloidea’ becomes a grade with four convergent appearances, when more taxa are added. Traditional paleontologists have been loathe to do this in their own cladograms. This hypothesis of interrelationships has been in the literature for the last 13 years (Peters 2007) and online in the LPT for the last ten. 

Keeping the blinders on
is what pterosaur workers seem to continue to be doing. The next generation of workers (Elgin and Hone among them) seems to be stuck in the same quagmire. Not sure why this is so. Astronomers and physicists are always testing each others’ observations and hypotheses. They are always inviting ideas. In the end, they seem to speak with one voice. Why can’t we be like that?


References
Elgin RA and Hone DWE 2020. A review of two large Jurassic pterodactyloid specimens
from the Solnhofen of southern Germany. Palaeontologia Electronica, 23(1):a13. https://doi.org/10.26879/741
palaeo-electronica.org/content/2020/2976-solnhofen-pterodactyloids
Peters D 2007. The origin and radiation of the Pterosauria. In D. Hone ed. Flugsaurier. The Wellnhofer pterosaur meeting, 2007, Munich, Germany. p. 27.

A Jurassic squid choking hazard for Rhamphorhynchus

Hoffmann et al. 2020 reported in no uncertain terms,
“Pterosaurs ate soft-bodied cephalopods (Coleoidea).”

Immediately after, Hoffmann et al. dialed it back a bit,
when they wrote, “Here, we report the first evidence of a failed predation attempt
by a pterosaur on a soft-bodied coleoid cephalopod.”

Based on size alone,
the squid (PIMUZ 37358) was more than a mouthful according to this ‘to scale’ diagram (Fig. 1)…at least more than a stomachful.

Ask yourself:
could a Rhamphorhynchus of that size (none were larger) eat a squid of that size? Did the pterosaur fail at predation? Or did it change its mind after biting the squid out of curiosity or boredom and losing a tooth in the process?

Figure 1. Plesioteuthis squid in situ with tooth. Reconstructions of Plesioteuthis (above) and the n81 specimen attributed to the largest known Rhamphorhynhcus, which has a matching tooth. The question is: could that pterosaur eat that squid? Or did it change its mind after biting the squid?

Figure 1. Plesioteuthis squid in situ with tooth. Reconstructions of Plesioteuthis (above) and the n81 specimen attributed to the largest known Rhamphorhynhcus, which has a matching tooth. The question is: could that pterosaur eat that squid? Or did it change its mind after biting the squid? At the very top is the hard tissue gladius of the squid to scale. That’s a hard part that would have been especially hard to swallow.

You be the judge.
Hoffmann et al. 2020 have provided the pertinent information. Above are the predator and “prey” to scale. Other Rhamphorhynchus specimens are smaller, and the tooth could have fallen from a different alveolus (a larger tooth) on a smaller specimen. Lots of variables and unknowns here. Also consider the difficulty of swallowing that long gladius, a hard part homologous with the cuttle bone in a cuttlefish.

In any case,
watch what headline you put on your paper. Here the authors went for maximum impact. If, like these authors, you have to dial it back in the second sentence of your abstract,  maybe a more conservative headline should reflect that assessment. After all, a dietary mainstay is indeed different than a curious nibble… and relative size matters.

We looked at other pterosaur choking hazards
earlier here. Pterosaurs likely swallowed their prey whole. There is no indication that they tore squids apart, creating bite-sized pieces. Likewise there is no indication that pterosaurs were able to expand their stomach to accommodate oversize prey (Fig. 1).


References
Hoffman R, Bestwick J, Berndt G, Berndt R, Fuchs D and Klug C 2020. Pterosaurs ate soft-bodied cephalopods. http://www.nature.com/scientificreports (2020) 10:1230 | https://doi.org/10.1038/s41598-020-57731-2

SVP abstracts – Daylight and lowlight Solnhofen pterosaurs

Cardozo, Sobral and Rodriques 2019 bring us
a new look at the vision of Solnhofen (Late Jurassic) pterosaurs.

From the abstract:
“Recent taxonomic reviews suggest that up to twelve genera of pterosaurs might have been present there.” 
Up to? There are twice a dozen distinct Rhamph-like taxa in the first row of figure 1, ignoring the other Solnhofen ‘wastebasket’ taxa Pterodactylus, Scaphognathus, Ctenochasma, Archaeopteryx, etc.
Traditional workers don’t count the little ones. Specialists don’t look closely at all the specimens. They ignore many. Some distinct taxa are found within traditional taxa like, Pterodactylus, Rhamphorhynchus and other generic wastebaskets. According to the LPT, no two pterosaurs scoring the same except for a juvenile/adult pairing in the Rhamphorhynchus wastebasket (Fig. 1).
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 1. 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.

Cardoza et al. continue:
“Even though many have been recovered from different chronostratigraphic 
units, the high taxonomic diversity and morphological disparity still suggest specializations that reflect distinct ecological roles. An endocast analysis of Pterodactylus antiquus, together with a literature review of the anatomy and ecology of these taxa, suggest interesting niche partitions.”
“Pterodactylus, Scaphognathus, and Rhamphorhynchus were generalist taxa that lived on
coastal areas and fed on fishes and small invertebrates.”
The authors are ignoring the distinct morphologies of these three genera and are not splitting up the small, medium and large taxa. Nor are they considering the distinct niches between adults and their 8x smaller hatchlings.
The descendants of Scaphognathus.

Fig. 2. The descendants of Scaphognathus. Note the size reduction followed by a size increase.

Cardoza et al. continue:
Their niche, however, did not overlap completely: our analysis corroborates a previous study that Pterodactylus had photopic
[daylight] vision, in contrast to the scotopic [dusk/night vision] type of Rhamphorhynchus. Scaphognathus was also photopic, but the different dentition indicates it was not preying on the same items as Pterodactylus.
Other taxa have been regarded as more specialists.
“Germanodactylus has been proposed as a durophage, based mostly on the lack of teeth on the tips of the rostrum and mandible, and therefore also likely preyed on different items than Pterodactylus. Anurognathus, Ctenochasma, Gnathosaurus, and Cycnorhamphus represent highly specialized taxa. Anurognathus was probably an aerial insectivore, with moderately curved unguals that are consistent with a scansorial habit, thus suggesting it inhabited forested areas. Ctenochasma and Gnathosaurus were filter feeders and their different sizes might have prevented, at least to some extent, niche overlap. The diet of
Cycnorhamphus is more disputed: it has been proposed as a durophage, a jellyfish specialist, or a generalist feeding on fishes and insects. In any case, its uniquely curved mandible with teeth only on the distal tip implies a different feeding niche from Solnhofen generalist pterosaurs. Lastly, the endocast of Diopecephalus kochi, a taxon that has been proposed as synonymous with Pterodactylus, was analyzed but poor preservation  prevented adequate assumptions on niche specializations.”
This is a list of old news, old traditions and old excuses. Where is the original thinking? Where are the pithy insights?
“Our preliminary analyses suggest that, although the Solnhofen archipelago was a rich pterosaur site, these taxa were not in direct competition, separated either by functional
anatomy or time. More data on paleoneurology is still needed to better understand niche occupation by Pterodactylus.”
In other words, we have nothing new to say, but wanted to come to Australia to make a presentation.

References
Cardozo FG, Sobral G and Rodriques T 2019. Ecological niches among pterosaurs from the Solnhofen archipelago. Journal of Vertebrate Paleontology abstracts.

Geographic cladogram of pterosaurs

So many pterosaurs come from so few places.
And those places are spread around the world. So, here (Fig. 1) is the large pterosaur tree (LPT, 239 taxa) with color boxes surrounding Solnhofen, Chinese, North American, South American and other geographic areas where they are found.

Figure 1. LPT with pterosaurs colorized according to geography.

Figure 1. LPT with pterosaurs colorized according to geography.

As before,
the traditional clades ‘Pterodactyloidea’ and ‘Monofenestrata‘ become polyphyletic when traditionally omitted taxa are included. Here (Fig. 1) four clades achieve the pterodactyloid-grade by convergence. Other pterosaur workers (all PhDs) omit or refuse to include most of these taxa, leading to false positives for the tree topologies they recover. Moreover, none recognize, nor cite literature for, the validated outgroup members for the Pterosauria (Fig. 1) preferring to imagine pterosaurs arising from unidentified and/or invalidated archosaurs or archosauriforms. Here we get to peak beneath the curtain.


References
Peters D 2000a. Description and Interpretation of Interphalangeal Lines in Tetrapods.  Ichnos 7:11-41.
Peters D 2000b. A Redescription of Four Prolacertiform Genera and Implications for Pterosaur Phylogenesis. Rivista Italiana di Paleontologia e Stratigrafia 106 (3): 293–336.
Peters D 2007. The origin and radiation of the Pterosauria. In D. Hone ed. Flugsaurier. The Wellnhofer pterosaur meeting, 2007, Munich, Germany. p. 27.

What is Alcmonavis poeschli?

Rauhut, Tischlinger and Foth 2019 describe
a disarticulated right forelimb/wing of a ‘non-archaeopterygid avialan theropod’, they named Alcmonavis poeschli specimen SNSB-BSPG 2017 I 133. It is the 13th Solnhofen bird.

The authors report,
“it is a more derived avialan than Archaeopteryx,” which brings up a problem.

Currently there are more than a dozen Solnhofen birds
or pre-birds in the large reptile tree (LRT, 1471 taxa). Many workers, including Rauhut, Tischlinger and Foth, throw them into a taxonomic wastebasket of ‘Archaeopteryx.’ Other authors have shown that some are not congeneric with others and these were noted by Rauhut, et al.

By contrast,
the LRT separates all of Solnhofen birds specifically, and many generically, recovering several at the bases of various Early Cretaceous bird clades. The LRT, employing relatively few forelimb traits and none specific to theropods/birds, nests Alcmonavis with the BSP 1999 I50 specimen identified as Archaeopteryx bavarica (the Munich specimen, Fig. 1), nesting at the base of the Jeholornis clade alongside the #12 specimen (Fig. 1), which nests at the base of the sister clade, the Scansoriopterygidae. Evidently there were enough traits in the new specimen forelimb to do this. I wasn’t sure at first.

Figure 1. Alcmonavis to scale with its sister in the LRT, the Munich specimen.

Figure 1. Alcmonavis to scale with its sister in the LRT, the Munich specimen. The authors did not attempt a reconstruction.

Notably,
Alcmonavis is twice the size of the Munich specimen (Fig. 1). The authors write, “Here we report on a new paravian specimen from the Lower Tithonian Mörnsheim Formation, representing the second theropod specimen from this unit, which overlies the Altmühltal Formation. The new specimen represents the largest avialan theropod yet recorded from the Jurassic and provides further evidence on the forelimb anatomy and the origin of flapping flight in basal avialans.”

The authors note that Alcmonavis
was found in the formation immediately above the one that yielded the majority of Solnhofen birds, including the Munich specimen.

Regarding the numbers and names, the authors write, 
“We propose to retain the original numbering of specimens, even if one accepts the different generic assignments, in order to avoid confusion between the recent and older literature. Given the gradual assembly of the avialan body plan and the general similarity of the basalmost members of this clade, it might be justified to simply talk about ’urvogel specimens’ instead of using the generic name Archaeopteryx, to thus accommodate the taxonomic uncertainty. Accordingly, the specimen described here should be regarded as the 13th urvogel specimen from the Solnhofen Archipelago.” 

This is confirmation of a practice already in place.
In the LRT and here at ‘Heresies’, all specimens from the Solnhofen limestones have been called, ‘Solnhofen birds’ for several years now. This leaves room for some specimen to be renamed when more of them are added to phylogenetic analyses, as documented in the LRT. The term ‘urvogel’ goes back to the false assumption that one ‘ur’ was present, rather than the large radiation already documented in the LRT.

The authors lament many layers of difficulty
in comparing the forelimb of Alcmonavis to those of other Solnhofen birds based on size and exposure, various proportions and robust qualities. As mentioned earlier, the LRT had no such problems using DGS methods to extract comparative data. Summarizing, the authors state, “despite the overall similarity and very similar proportions, the new specimen shows numerous small differences from Archaeopteryx, precluding a referral to this taxon. It is furthermore clear that SNSB-BSPG 2017 I 133 also cannot be referred to Ostromia or to any other known theropod taxon.”

“The phylogenetic analysis resulted in more than 99,999 trees with a length of 2690 steps. The strict consensus is rather well resolved and includes monophyletic Maniraptora, Paraves and Avialae with equivalent taxonomic contents to other recent analyses.”

Unfortunately the authors include only one taxon for Archaeopteryx.
They nest Alcomonavis between Archaeopteryx and higher birds, oblivious to the effects of taxon exclusion on their tree topology. Little else needs to be said. Deleting/ omitting/ ignoring key taxa is inappropriate at this stage of our understanding of Solnhofen birds.

Here is yet another case
where more taxa would have helped the original authors, not more characters. Taxon exclusion continues to be the number one problem in paleontology, not just with Jurassic birds.

Contra the title of Rauhut et al. 2019,
the new taxon is indeed an archaeopterygid, despite its size.


References
Rauhut OWM, Tischlinger H and Foth C 2019. A non-archaeopterygid avialan theropod from the Late Jurassic of southern Germany. elifesciences.org 2019;8:e43789. DOI: https://doi.org/10.7554/eLife.43789

You heard it here first: No two Archaeopteryx look the same.

The science section
of the online British news outlet, the Guardian, reported on the 12th (Haarlem) specimen of Archaeopteryx re-named Ostromia. You can read that story online here.

From the Guardian article:
“Of the Twelve Specimens Once Known as Archaeopteryx (SPOKA), only nine continue to carry that name. At the end of the day, we can’t all be winners. But even within that group of nine specimens, no two Archaeopteryx look the same. Rauhut and colleagues report that there is significant variation in the size, shape, spacing and orientation of the teeth, as well as differences in body size between the different specimens. This could be an ontogenetic pattern, with larger individuals representing adults with more developed dentition. Alternatively, as the Solnhofen Basin constituted a tropical island archipelago during the Late Jurassic, these differences in body size and dentition could be interpreted as island adaptations. Similarly to today’s Galápagos finches, different populations of Archaeopteryx may have adapted to different insular environments.”

We looked at
Solnhofen birds (Fig. 1) earlier here and Ostromia here. Since 2015 readers have known that no two Archaeopteryx specimens were identical and that phylogenetic analysis split them apart to nest at the base of each one of all the Cretaceous bird clades. And yes, we know of an embryo archaeopterygid, the Liaoning embryo most closely related to the London specimen.

Figure 3. Several Solnhofen birds, including Archaeopteryx, compared to Ostromia to scale.

Figure 3. Several Solnhofen birds, including Archaeopteryx, compared to Ostromia to scale.

It really is time to
run these birds through analysis and either affirm, modify or invalidate the results of the large reptile tree. And it should be done by someone with firsthand access to all the specimens. That would be a good test.

References
Elzanowski, A., 2002. Archaeopterygidae (Upper Jurassic of Germany) In: Chiappe LM, Witmer LM, eds. Mesozoic Birds. Above the Heads of Dinosaurs. Berkeley: University of California Press. 129-159.
Foth C, Rauhut OWM. 2017. Re-evaluation of the Haarlem Archaeopteryx and the radiation of maniraptoran theropod dinosaurs. BMC Evolutionary Biology 17:236

https://www.theguardian.com/science/2018/feb/21/the-new-specimen-forcing-a-radical-rethink-of-archaeopteryx

The 11th Archaeopteryx: closer to Sapeornis

Figure 1. The 11th specimen attributed to Archaeopteryx in situ. See figure 2 for a reconstruction. This specimen remains in private hands without a museum number.

Figure 1. The 11th specimen attributed to Archaeopteryx in situ. See figure 2 for a reconstruction. This specimen remains in private hands without a museum number. Note all the soft tissue feathers preserved here.

Archaeopteryx number 11
(Figs. 1, 2) has no museum number and is in private hands, but Foth et al. 2014 published a description in Nature. These authors unfortunately considered this specimen just another Archaeopteryx, but one well supplied with feather impressions. In the large reptile tree (LRT, subset Fig. 3) this Solnhofen bird nests at the base of the node that produced two specimens of Sapeornis, a clade convergent with Euronithes in having a pygostyle.  The 11th specimen is complete and articulated, but lacks a large part of the cranium.

Figure 2. Most of the complete Solnhofen birds, including Archaeopteryx and the eleventh specimen to scale.

Figure 2. Most of the complete Solnhofen birds, including Archaeopteryx and the eleventh specimen to scale.

Foth et al. 2014 do not mention
the lack of a sternum. Sapeornis likewise lacks a sternum even though more primitive taxa have one.

Figure 4. The eleventh Archaeopteryx nests with Sapeornis.

Figure 4. The eleventh Archaeopteryx nests with Sapeornis.

At first glance
this appears to be an ordinary Archaeopteryx. However, when you put the dividers on the bones you find that it differs in subtle ways from the holotype and is more similar to Sapeornis and its sisters. As I mentioned yesterday, it would be a good thing for all early bird workers to start considering the Solnhofen birds individual genera, not a single genus. It’s just a lazy habit we have to overcome.

References
Foth C, Tischlinger H and Rauhut OWM 2014. New specimen of Archaeopteryx provides insights into the evolution.of pennaceous feathers. Nature 511:79–83.DOI: 10.1038/nature13467

Solnhofen “Find a Twin” Contest

Readers,
I’ve looked at many dozen Solnhofen pterosaur specimens and haven’t yet found two that are identical.

If you can present me/us with two identical Rhamphorhynchus or Pterodactylus I will make the announcement. Send in pictures or museum numbers, please.

I haven’t compared every specimen to every other one yet, but I’m not sure we can find two identical specimens. There is an incredible variety out there.

The most likely scenario would be to find two conspecific pterosaurs on the same slab, but I don’t think there is such a thing yet discovered.

A new(?) tiny “pterodactyloid” (from 1841!) with a short neck

 Tiny Pterodactylus? pulchellus (=micronyx) from the National History Museum London. Some DGS has been applied to bring out certain details.

Figure 1. Tiny Pterodactylus? pulchellus (=micronyx) from the Natural History Museum London. Some DGS has been applied to bring out certain details. If your screen resolution is 72 dpi, then you’re seeing this fossil full size.

In the new book, Pterosaurs (Witton 2013:198), a tiny pterosaur with a 3 cm long skull with a long rostrum was pictured (Fig. 1). Witton identified the tiny pterosaur as a juvenile in the Natural History Museum London collection. After process of elimination, I’m guessing this is a Solnhofen (Late Jurassic) specimen PV R 2721 attributed by Meyer (1841) to Pterodactylus puchellus. [I could be wrong.] Later workers called it P. micronyx. I don’t know the Wellnhofer (1970) number.

Here it is at full scale (Fig. 1, if your screen is set to 72dpi). The inset shows the pes reconstructed. The pes alone with its long metatarsal 1 identifies it as a descendant of the scaphognathids (Peters 2011). Phylogenetic analysis nested it between another tiny pterosaur (but slightly larger) with a shorter rostrum, GMU-10157 (Fig. 2) and Cycnorhamphus (Fig. 3) a much larger specimen.

Notice the resemblance? 

. GMU-10157 (above) and the Meyer 1841 specimen (below) to the same scale.

Figure 2. GMU-10157 (above) and (I think) the Meyer 1841 specimen PV R 2721 (below) to the same scale. The Meyer specimen is slightly smaller overall, yet has a longer rostrum and nests at the base of the Cycnorhamphus clade. GMU-10157 nests at the base of the cycnorhamphids + ornithocheirids.

The interesting thing…
The Meyer 1841 specimen is actually smaller than GMU-1-157, and yet it has a longer rostrum! That breaks one of the “rules” under the old allometric ontogenetic growth paradigm. Here these two tiny adults are part of a long gradual evolutionary continuum of size reduction and enlargement (Fig. 3). And this, ladies and gentlemen, is how you evolve a Cycnorhamphus. It’s the closest known outgroup taxon. Further out GMU-10157 nests at the base of the cycnorhamphids + ornithocheirids.

Cycnorhamphus, its sisters and predecessor taxa

Figure 3. Cycnorhamphus, its sisters and predecessor taxa, sans the Meyer 1841 specimen.

Witton (2013) considered Cycnorhamphus a ctenochasmatoid, related to Pterodactylus and Ctenochasma. They’re not related according to the results of the large pterosaur family tree (where the Meyer specimen will shortly be added). You have to go back to Dorygnathus to find a last common ancestor. If you eliminate Ctenochasma then Scaphognathus is the last common ancestor. Obviously, given the generic name Meyer (1841) applied to this specimen, this sort of mistake has been going on for a long, long time.

Reconstruction of the tiny London specimen.

Figure 4. Reconstruction of the tiny London specimen, shown larger than actual size. Derived from a sister to the GMU specimen (Fig. 2), the London specimen was ancestral to cycnhorhamphids. A great pes subdivided by PIL (parallel interphalangeal lines). You can even see the very beginnings of that dentary bend that reaches its acme in the bent-jaw cyc (Fig. 3). But no long legs yet.

The short neck problem
Darwinopterus was promoted as a transitional pterosaur, having the long rostrum and long neck of a pterodactyloid, but the remainder of the body with its long tail and long toe 5 were pre-pterodactyloid. The Meyer specimen, along with others, then presents a problem. It has a short neck and, for that matter, a shorter rostrum than Darwinopterus. GMU 1-157 has an even shorter rostrum. TM-13104 (Fig. 3) has an even shorter rostrum and longer metacarpals, yet it nests as a descendant of Scaphognathus.

Expectations and reality all fall apart rather quickly if you hang your hat on Darwinopterus, a specimen that is a “dead end” taxon in the large pterosaur family tree. Expand the gamut in your taxon list and see what new relationships emerge.

No such problems here.
If you don’t believe me that this is a tiny adult in the lineage of cycnorhamphids, just add it to your own analysis. Repeating the test is good Science. Throwing insults from the sidelines is not, unless they come with good evidence in tow. It is also possible that this specimen is young. Without an eggshell beside it, the tiny pterosaurs give few clues as to their ontogenetic age, other than their phylogenetic nestings and the sizes of their sisters. Here the sizes vary considerably.

Pterosaur workers have been avoiding tiny pterosaurs, denigrating them as pre-morph juveniles, when tiny pterosaurs hold the key to understanding pterosaur relations. Similarly pterosaur workers have been avoiding tritosaur/fenestrasaur/lepidosaurs, when they hold the key to pterosaur origins.

Take a good look at that skull
With that long concave rostrum, procumbent anterior teeth and pelvis shape in the Meyer specimen, we’re getting very close to the morphology of Cycnorhamphus. There’s no fronal/parietal crest yet. The long neck, long legs and longer metacarpals were yet to come. The free fingers were likewise getting close in proportion to one another.

If this is not the Meyer 1841 specimen,  PV R 2721, please let me know to make the correction.

References
Witton M. 2013. Pterosaurs. Princeton University Press. 291 pages.