Palaeogeranos tourmenti gen. nov. et sp. nov. (1 Viewer)

[Fred Ruhe]

Antoine Louchart & Anais Duhamel, 2021

A new fossil from the early Oligocene of Provence (France) increases the diversity of early Gruoidea and adds constraint on the origin of cranes (Gruidae) and limpkin (Aramidae)

Journal of Ornithology in press

A new fossil from the early Oligocene of Provence (France) increases the diversity of early Gruoidea and adds constraint on the origin of cranes (Gruidae) and limpkin (Aramidae) - Journal of Ornithology

Cranes (Gruidae) have a poor early fossil record, and the oldest ascertained fossils hitherto referred to the family (either as crown or stem-representatives) date back to the early or middle Miocene. Other Gruoidea have an even scarcer fossil record. Psophiidae and Aramidae are virtually...

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DOI: https://doi.org/10.1007/s10336-021-01891-z

Abstract

Cranes (Gruidae) have a poor early fossil record, and the oldest ascertained fossils hitherto referred to the family (either as crown or stem-representatives) date back to the early or middle Miocene. Other Gruoidea have an even scarcer fossil record. Psophiidae and Aramidae are virtually unknown as fossils, and other fossil representatives of the Gruoidea are difficult to place. Here, we describe a new fossil that sheds new light on the early history of stem Gruidae, a right coracoid in dorsal view preserved on slab in limestone laminites of the early Oligocene « Calcaires de Campagne-Calavon» (Alpes de Haute Provence, France). It is compared with extant and fossil morphologically related taxa, and appears to differ from all extant and fossil relatives in the Gruoidea. The new fossil represents, among the Gruoidea, a new genus and species, Palaeogeranos tourmenti, placed within the clade (Aramidae + Gruidae) that is referred to as epifamily Gruoidae. Within Gruoidae, placement is tentative and we give arguments leading to propose a possible position as a stem Gruidae, a hypothesis to be tested with further discoveries. In this hypothesis, aged around 30 million years, the new fossil suggests that the stem of the Gruidae would date back to at least the earliest Oligocene, which is still compatible with current molecular phylogenetic divergence dates estimations, given the confidence intervals. Palaeogeranos will potentially help refining future calibrations for molecular phylogenetic studies, at least concerning the earliest Gruoidae (Aramidae + Gruidae).

Enjoy,

Fred

 

[ornithociencia]

Hi Fred, do you have the figures of this paper?

 

[Fred Ruhe]

Hi Fred, do you have the figures of this paper?

Everything comes when I received the paper. It is on its way.

Fred

 

[Fred Ruhe]

Systematic palaeontology

Class Aves Linnaeus, 1758
Order Gruiformes Bonaparte, 1854
Suborder Grues Bonaparte, 1854
Superfamily Gruoidea Vigors, 1825
Epifamily Gruoidae Vigors, 1825
?Family Gruidae Vigors, 1825

Palaeogeranos, gen. nov.
LSID urn:lsid:zoobank.org:act:85566356-D102-46C8 A90F-5B40A1B0B35E.

Type and only included species.

Palaeogeranos tourmenti, sp. nov.

Differential diagnosis

Palaeogeranos is a crane-like bird, of rather small dimensions, ca 70% of a Balearica species in coracoid medial length. Palaeogeranos differs more importantly from all other avian taxa than from extant Gruidae. Among extant Gruidae, Palaeogeranos differs from the Gruinae as follows: sterno-coracoidal fossa rounder; outline of the sternal border slightly less concave; latero-sternal end less expanded sternad; angulus externus more obtuse and less protruding; processus externus more rounded and much less protruding; an obtuse angle in outline visible between the processus procoracoideus and the medial outline of the coracoideus corpus; portion from cotyla scapularis to omal end relatively Palaeogeranos differs from the Balearicinae (Balearica) in: processus lateralis slightly narrower; processus externus rounder and less protruding; an obtuse angle in outline visible between the processus procoracoideus and the medial outline of the coracoideus corpus (angle absent in Balearica); portion from cotyla scapularis to omal end relatively slightly shorter than in Balearica. Palaeogeranos differs, among comparable fossil taxa, from Geranopsis hastingsiae (Gruoidea) in: more developed acrocoracoid, cotyla scapularis, and facies glenoidalis (the latter enlarged more distally); more enlarged processus procoracoideus; wider sternal end with angulus medialis much more protruding medially as an acute angle; more developed processus lateralis; sterno-coracoidal fossa smaller and more central; from Parvigrus pohli (Parvigruidae) in: angulus medialis more pointed; outline of the sternal border more concave; medial edge from base of processus procoracoideus to angulus medialis much more concave; whole latero-sternal end much more expanded sternally; processus lateralis almost square-shaped; coracoid corpus narrower (at mid-length); processus procoracoideus wider (omalo-sternally); tuberculum brachiale more prominent; from Rupelrallus saxoniensis (Parvigruidae) at least in: angulus medialis much less expanded sternad; outline of the sternal border less concave; more developed processus lateralis; and from Camusia quintanai (Gruidae) in: portion from cotyla scapularis to omal end relatively shorter; coracoid corpus narrower (at mid-length); sterno-coracoidal fossa larger; absence of an angle between the medial border of corpus and the omalo-medial border of the angulus medialis.

Etymology.

From the greek palaios geranos (crane), to reflect the morphological similarity of the fossil with cranes, and its relatively old age.

Palaeogeranos tourmenti, sp. nov.
LSID urn:lsid:zoobank.org:act:8A1741B1-C9B4-4F55-
8F5C-B8792F58DB34.

Holotype.

Complete right coracoid on slab, showing dorsal aspect, n° UCBL-FSL-444667, in the Collections of the Faculté des Sciences de Lyon, Université Lyon 1, Villeurbanne, France.

Type locality and horizon.

The locality is Limans (Alpes de Haute Provence, southeastern France; 43.9861° N, 5.7311° E). The formation, called “Calcaires de Campagne-Calavon”, is Rupelian, 33.9–27.82 Ma, early Oligocene (Cavelier 1984; Escarguel et al. 1997; Sigé and Hugueney 2006).

Diagnosis.

As for genus.

Etymology.

Named after Nicolas Tourment, for his long scientific cooperation, and precious contribution to palaeornithology, and who donated the present specimen to the collections of Université Lyon 1.

Fred


Fig. 1 The new fossil coracoid UCBL-FSL-444667, of Palaeogeranos tourmenti n. gen. n. sp. (d drawing after the actual fossil; j, photograph of fossil on slab), compared with extant and fossil representatives of the Gruoidea. a Grus (Bugeranus) carunculata; b Grus grus; c, Grus (Anthropoides) virgo; e, f Balearica pavonina g Psophia crepitans; h Aramus guarauna; i Balearica egulorum k Rupelrallus saxoniensis; l Parvigrus pohli. All right coracoids in dorsal view except (l), which is a left coracoid in ventral view, useful in outline comparison, and except (b,h,i), which are left coracoids (in dorsal view) that were mirrored for convenience. (i), modified after photograph in Mayr (2016). k,l Modified after photographs in Mayr (2013). ae, angulus externus; am, angulus medialis; chs*, coraco-humeral surface (after Howard 1929); cs, cotyla scapularis; fac, facies articularis clavicularis; fah, facies articularis humeralis; fas, facies articularis sternalis; fsc, foramen supracoracoideum; fg, facies glenoidalis; ims, impressio m. sternocoracoidei; pa, processus acrocoracoideus; pe, processus externus; pl, processus lateralis; pp, processus procoracoideus; scf**, sterno-coracoidal fossa (after Gilbert et al. 1981), which is deep in P. tourmenti (and filled with sediment); tb, tuber brachialis (all terms after Baumel and Witmer 1993, except for the ones marked with asterisks, and the ones in italics that derive from Ballmann 1969). Small arrows indicate the principal differences from P. tourmenti, observed in extant Gruidae, and on the other hand in the fossil taxa Rupelrallus and Parvigrus. Scale bars, 10 mm

Fig. 2 Phylogenetic position hypothesized for Palaeogeranos tourmenti n. gen. n. sp. This proposed possible position derives from comparisons with other Gruoidea. Other fossil Gruoidea are also placed, based on the literature (see text). The phylogenetic frame of extant taxa derives from Kuhl et al. (2020). The 95% confidence interval is shown (bar and limits on either side of average date marked by X, the latter being the age of maximal probability) for the node (Gruidae + Aramidae) based on Kuhl et al. (2020). The approximate position of P. tourmenti proposed here takes into account this
wide interval. We placed here the node (Gruidae + Aramidae) at an earlier date than the average (maximum probability age), but still within the 95% confidence interval, at ca. 35 Ma (circle). Consequently, P. tourmenti can possibly be considered posterior to this node (Gruidae + Aramidae) and as a ?stem Gruidae (see text). Alternatively, it might be slightly more basal, slightly stemward from this node, on the stem of Gruoidae (Aramidae + Gruidae). Squares indicate the age of crown Balearicinae and crown Gruinae, based on One-Zoom Tree of Life Explorer (Jetz et al. 2012; Rosindell and Harmon 2012). The timescale is logarithmic to avoid compression of branchings of interest here. Crosses indicate fossil taxa.

 

[Fred Ruhe]

Correction:

In the Differential diagnosis of the genus, a sentence was lost:

"portion from cotyla scapularis to omal end relatively" must read: "portion from cotyla scapularis to omal end relatively
shorter; processus acrocoracoideus less twisted"

Fred

 

[Angry Bird]

Dear colleagues,
I am surprised because it seems that you have here an old version of the manuscript ; for example in the final, published version there are 3 figures instead of 2, and the simplified phylogenetic tree is Figure 3 ; (they are visible on the website of the journal even without full access) ;
... so probably in the version above here other things are obsolete !
Best,
Antoine

 

[Fred Ruhe]

Dear Antoine,

I used the complete version of the paper, but I never find it correct to give all the text and all the figures. I leave something to discover for the people who are interested in paleornthology, unfortunately, very few.

Fred