DOI: 10.5061/dryad.70rxwdc4s
title: Data from: Echericetus novellus n. gen. n. sp. (Cetacea: Mysticeti: Eomysticetidae), an Oligocene baleen whale from Baja California Sur, Mexico

description: Among the several evolutionary lineages of the baleen whales (Mysticeti),
 the eomysticetids are an ancient successful family that retain possibly
 non-functional teeth and functional baleen, a transitional stage between
 toothed and baleen-assisted filter-feeding mysticetes. However, the patchy
 fossil record leaves gaps in eomysticetids palaeobiology interpretations
 but their diversity and widespread geographical distribution can be a
 relevant proxy to understanding the evolution of crown Mysticeti. Here, we
 describe a new baleen whale, Echericetus novellus n. gen. n. sp., from the
 Oligocene of Mexico (slightly older than 27.95 million years ago). This
 new taxon has morphological features that show its affinity to
 Eomysticetidae, such as the intertemporal region longer than wide,
 elongate and oval temporal fossa, and a well-developed and lobate coronoid
 process of the mandible. Similarly, our cladistic analyses confirm the
 inclusion of Echericetus in the Eomysticetidae. Echericetus reinforces our
 notion of the eomysticetid diversity and disparity. Geographically, the
 existence of Echericetus from Mexico also indicates that eomysticetids
 inhabited subtropical regions in the Northern Hemisphere. Lastly, our
 discovery of a new eomysticetid from the Oligocene of Mexico provides new
 insights into the distribution patterns and habitat use of Eomysticetidae,
 essential to further explain the demise of this transitional lineage
 between toothed and baleen-bearing whales.
description: # Echericetus novellus n. gen. n. sp. (Cetacea: Mysticeti:
 Eomysticetidae), an Oligocene baleen whale from Baja California Sur,
 Mexico This Hernández
 Cisneros Schwennicke Rochín-Bañaga and Tsai_README.txt file was generated
 on 2023-10-07 by CH Tsai A. GENERAL INFORMATION A.1. Principal
 Investigator Contact Information Name: CHENG-HSIU TSAI Institution:
 Department of Life Science and Institute of Ecology and Evolutionary
 Biology, National Taiwan University Email: ;
 A.2. Co-investigator Contact Information Name:
 Atzcalli Ehécatl Hernández Cisneros Institution: Instituto Politécnico
 Nacional Email: Name: Tobias Schwennicke
 Institution: Universidad Autónoma de Baja California Sur Email:
 Name: Heriberto Rochín-Bañaga Institution:
 University of Toronto Email:
 B. SHARING/ACCESS
 INFORMATION B.1. Licenses/restrictions placed on the data: CC0 (Dryad
 Repository) B.2. Links to publications that cite or use the data:
 Hernández Cisneros AE, Schwennicke T, Rochín-Bañaga H, and Tsai CH. 2023.
 Echericetus novellus n. gen. n. sp. (Cetacea: Mysticeti: Eomysticetidae),
 an Oligocene baleen whale from Baja California Sur, Mexico. Journal of
 Paleontology. C. DATA & FILE OVERVIEW C.1. File List: Hernández
 Cisneros Schwennicke Rochín-Bañaga and Tsai 2023 Echericetus Supp Info
 Oct07.docx Hernández Cisneros Schwennicke Rochín-Bañaga and Tsai 2023
 Echericetus Supp Info Oct07 ordered.nex D. METHODOLOGICAL INFORMATION D.1.
 Description of methods used for collection/generation of data: The
 phylogenetic analysis was performed based on the original data matrix from
 Marx and Fordyce (2015), including recent updates from Hernández-Cisneros
 and Nava-Sanchez (2022) and Hernández-Cisneros (2022). We also reviewed
 coded characters for Maiabalaena and Sitsqwayk. The following characters
 were changed in both taxa: character (c.) 26 coded from the state (s.) “?”
 to “1” (teeth in adult individuals absent or vestigial, see discussion on
 baleen origins; Ekdale and Deméré, 2022; Gatesy et al., 2022); c. 83 from
 s. “2” to “1” (the temporal fossa form a large parasagittal oval); c. 100
 from s. “0” to “2” (almost 90 degrees twisting of the zygomatic process of
 squamosal). For Maiabalaena, c. 11 from s. “?” to “1” (antorbital process
 present and defined by a steep face separating the posterolateral corner
 of the maxilla from its more anterior rostral portion); c. 103 from s. “0”
 to “1” (absent supramastoid crest of the zygomatic process of squamosal).
 For Sitsqwayk, c. 24 from s. “?” to “1” (a straight facial portion of the
 rostrum in lateral view). Also, the following characters in Tlaxcallicetus
 guaycurae were changed: c. 83 from s. “2” to “?”, c. 99 from s. “0” to
 “?”, c. 117 from s. “2” to “1”, c. 119 from s. “1” to “0”, c. 132 from s.
 “1” to “0”, c. 136 from s. “0” to “1”, c. 160 from s. “0” to “?”, c. 161
 from s. “0” to “?”, c. 187 from s. “0” to “0&1”. The present matrix of
 272 characters has 112 terminal taxa (see the supplemental files;
 Hernández Cisneros et al., 2023). D.2. Methods for processing the data: we
 inactivate unpublished taxa (not ready for re-examination) and
 poorly-preserved species (e.g. Willungacetus). Thus, 106 taxa were treated
 under the parsimony analysis using T.N.T. v.1.5 software (Goloboff and
 Catalano, 2016). Characters were analyzed under equal and implied weights
 (under the standard value k= 3 and the calculated k=28.18360 using the
 script “setk”; Goloboff, 1993; Goloboff et al., 2008; Goloboff et al.,
 2018), ordered and using a backbone constraint tree –force / (5 ((16 51)
 (33 (48 ((19 21) ((26 73) (24 (22 25))))))));–. Settings include
 10,000-random stepwise-addition replicate per tree, bisection reconnection
 (TBR) branch swapping with ten trees per replicate and enforce
 constraints. The multiple most parsimonious trees were summarized under
 strict consensus. Support values were obtained by symmetric resampling
 based on 2000 replicates and reported as GC frequency differences
 (Goloboff et al., 2003). Under equal weights, a second analysis was run
 due to overflow replications using saved trees in the memory from the
 first result. Only the consensus tree resulting from the implied weights
 (k= 28.18360) is explained regarding the specimen MRAHBCS Pal/V119. D.3.
 Instrument- or software-specific information needed to interpret the data:
 PDF viewer, TNT software for cladistic analysis. D.4. Standards and
 calibration information, if appropriate: Not applicable D.5.
 Environmental/experimental conditions: Not applicable D.6. Describe any
 quality-assurance procedures performed on the data: Not applicable (see
 link to publication for details) D.7. People involved with sample
 collection, processing, analysis and/or submission: Hernández Cisneros AE,
 Schwennicke T, Rochín-Bañaga H, and Tsai CH. E. DATA-SPECIFIC INFORMATION
 FOR: Hernández Cisneros Schwennicke Rochín-Bañaga and Tsai 2023
 Echericetus Supp Info Oct07.docx N/A F. DATA-SPECIFIC INFORMATION FOR:
 Hernández Cisneros Schwennicke Rochín-Bañaga and Tsai 2023 Echericetus
 Supp Info Oct07 ordered.nex N/A \[END OF Hernández Cisneros Schwennicke
 Rochín-Bañaga and Tsai_README.txt] Links to publications that cite or use
 the data: Hernández Cisneros AE, Schwennicke T, Rochín-Bañaga H, and Tsai
 CH. 2023. Echericetus novellus n. gen. n. sp. (Cetacea: Mysticeti:
 Eomysticetidae), an Oligocene baleen whale from Baja California Sur,
 Mexico. Journal of Paleontology.