Tynskya and Messelastur enter the LRT with overlooked bird taxa

Today
two birds enter the LRT, nesting at nodes the experts overlooked. Both were considered closely related members of the clade Messelasturidae. “Initially interpreted as stem-owls, more recent studies have shown that they are actually closely related to modern parrots and are in the same order, Psittaciformes,” according to Wikipedia.

Not true in the LRT.

Backstory #1:
Didunculus, the tooth-billed pigeon (Fig. 1) does not nest in the large reptile tree (LRT, 1807+ taxa) with pigeons or dodos. Instead Didunculus nests with Falco, the falcon, far from pigeons, close to owls, owlets and swifts, something we learned a few years ago.

Figure 2. Figures of the Didunculus skeleton.

Figure 1. Figures of the Didunculus skeleton.

Today’s first bird is
Messelastur (Fig. 2) from the famous middle Eocene Messel pit.

Figure 2. Messelastur skull with colors added.

Figure 2. Messelastur skull with colors added. Note the displaced beak tip and another possible displaced premaxillary bone.

The literature on Messelastur includes:

Peters 1994 (not me) considered Messelastur a member of the Accipitridae (= hawks, eagles, Old World vultures and kin, but not owls). Note the sharp predaceous beak.

Mayr 2005 wrote: “They [Messelasturidae] provide a morphological link between Strigiformes and Falconiformes (diurnal birds of prey), and support the highly disputed falconiform affinities of owls in combining derived tibiotarsus and tarsometatarsus characters of owls with a more plesiomorphic, ‘falcon-’ or ‘hawk-like’, skull morphology.”

Wikipedia 2021 reports, “more recent studies have shown that they are actually closely related to modern parrots and are in the same order, Psittaciformes.” Psittaciformes = parrots (Fig. 3). The Wiki author was citing:

Mayr 2011, who wrote, “If future data strengthen their psittaciform affinities, they not only add a distinctive new taxon to the stem lineage of Psittaciformes, but also show that some stem group Psittaciformes were predatory birds.”

When added to the LRT
Messelastrus nests not with parrots (Fig. 3), but with Didunculus (Fig. 1). Parrots still nest with hoatzins, giant flightless parrots, sparrows and chickens far from hawks, owls and kin.

Figure 3. Skeleton of Ara macao, the scarlet macaw. Note the skeleton has pedal digits 3 and 4 switched.

Figure 3. Skeleton of Ara macao, the scarlet macaw. Note the skeleton has pedal digits 3 and 4 switched.

Backstory #2:
Apus,
the common swift, does not follow tradition and nest with hummingbirds in the LRT. Rather, as we learned several years ago the swift nests with Aegotheles, the owlet, close to owls and other predatory birds.

Figure 2. Apus the common swift is actually a close relative of the falcon and owl, not a hummingbird.

Figure 4. Apus the common swift is actually a close relative of the falcon and owl, not a hummingbird.


Mayr 2000 first described

Tynskya (Fig. 4) an early Eocene Green River bird he considered a link between falcons and owls. In the LRT Tynskya nests with Apus, the swift (Fig. 4), not far from falcons and owls. The skull of Tynskya had huge eyes and a tiny beak, just like Apus, along with hundreds of other aligning traits.

Figure 5. Tynskya in situ and with some parts pulled out for clarity. Apparently the pelvis and backbone are still buried in this ventral view of the torso, dorsal view of the skull after neck torsion.

Figure 5. Tynskya in situ and with some parts pulled out for clarity. Apparently the pelvis and backbone are still buried in this ventral view of the torso, dorsal view of the skull after neck torsion. The ‘x’ marks a broken humerus.The broken sternum is reassembled at lower left.

As you can see,
in both new taxa (above) more closely related taxa were excluded, something the LRT is designed to minimize. Minimizing taxon exclusion will help you nest taxa that display traits convergent with unrelated taxa, like hawks and parrots. Fewer enigmas result, if that’s okay with you. Enigmas and mysteries make paleontology more interesting and intriguing. Unfortunately, the LRT has removed many over the last ten years.


References
Mayr G 2000a. A new raptor-like bird from the Lower Eocene of North America and Europe. Senckenbergiana lethaea 80:59–65.
Mayr G 2005. The postcranial osteology and phylogenetic position of the Middle Eocene Messelastur gratulator Peters, 1994—a morphological link between owls (Strigiformes) and falconiform birds? Journal of Vertebrate Paleontology 25(3):635–645.
Mayr G 2011. Well-preserved new skeleton of the Middle Eocene Messelastur substantiates sister group relationship between Messelasturidae and Halcyornithidae (Aves, ? Pan-Psittaciformes). Journal of Systematic Palaeontology 9(1):159-171.
Peters DS 1994. Messelastur gratulator n. gen. n. spec., ein Greifvogel aus der Grube Messel (Aves: Accipitridae). Courier Forschungsinstitut Senckenberg 170:3–9.

wiki/Accipitridae
wiki/Didunculus
wiki/Tooth-billed_pigeon

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