Viglino, Mariana; Gaetán, Maximiliano; Cuitiño, José I. & Buono, Mónica R.

1. Oh my teeth!
Odontocetes feeding methods
diversification in the early
Miocene
Viglino, Mariana; Gaetán, Maximiliano; Cuitiño, José I. & Buono, Mónica R.
IPGP, CCT CONICET-CENPAT, Puerto Madryn, Chubut,Argentina
viglino@cenpat-conicet.gob.ar

2. Introduction
Miocene
Waipatia
maerewhenua
Notocetus vanbenedeni
Phoberodon arctirostris
Ninjadelphis ujiharai
Aondelphis
talen
Dilophodelphis
fordycei
Squalodon calvertensis
Platanista gangetica
Extant riverine representative
Huaridelphis raimondii
50mm
Prosqualodon australis
Goedertius oregonensis
Otekaikea
marplesi
Source: www.fossilworks.org
Araeodelphis natator
Late Oligocene
Platanistoidea (Odontoceti, Cetacea)

3. Materials and Methods
Geographic and stratigraphic location of holotype. Source: Viglino et
al. (2020)
Geological Setting: lower Miocene outcrops,
Gaiman Fm.
Estimating missing rostrum in holotype,
to reconstruct the feeding method of the
species. Linear regression (9 sp, n=15). R2=
0.83
Reconstructing feeding methods: skull,
mandibles, teeth and hyoid apparatus characteristics.
Soft tissues for extant sp. Johnston & Berta (2011).
• Capture suction feeders: use suction to capture
and ingest prey.
• Raptorial feeders: slight suction or none at all.
• Combination suction feeders: use suction to ingest
prey.
Phylogenetic analyses in TNT. Equal and implied
weights. Morphological matrix (89 OTU, 286
characters). Source: Viglino et al. (2020)

4. Results
Dorsal (top) and lateral (bottom) views of the
holotype. Source: Viglino et al. (2020)
Dolgopolis kinchikafiforo gen. et sp. nov.
Missing rostrum: 112mm
CBL (e) = 613 mm  Mesorostrine
-Recovered as a stem Physeteroidea+Ziphioidea
(spurious result due to homoplasy and convergence).
-Implied weights recovered as a Platanistoidea (but
with no certain phylogenetic position within the
group).
Key characteristics of D. kinchikafiforo:
-Medium-length rostrum; mediolaterally compressed
premaxilla anteriorly.
-Intertemporal constriction
-Absence of defined alveoli (thus, no teeth)
-Lacrimojugal forming posterior wall of AON
-Concave paroccipital process
-Wide basioccipital
-Squared-like jugular notch
Dra. Mathilde
Dolgopol

5. Discussion and conclusions
-Dolgopolis kinchikafiforo is the first toothless
capturse-suction platanistoid.
-Capture-suction feeding method recorded since
the Oligocene; convergent evolution.
-Delphinida has higher taxonomic diversity but a
single predominant feeding method (combination
suction).
-Platanistoidea initial radiation related to diverse
morphotypes and ecological strategies.
Finantial support
Predominance of Platanistoidea during the early
Miocene in America and Europe. Diversity in sp
and feeding strategies. Later decline at middle-Late
Miocene possibly related to ecological factors?
Dolgopolis kinchikafiforo is a member of
Platanistoidea, but need to further study its
phylogenetic position within the group
Optimization of feeding strategy character in
phylogenetic hypothesis. Source: Viglino et al. (2020)