Phylogenetic relationships of Chanidae (Teleostei: Gonorynchiformes) as impacted by Dastilbe moraesi , from the Sanfranciscana basin, Early Cretaceous of Brazil

Abstract

Fossil gonorynchiform fishes range from the Lower Cretaceous to the early Miocene, and are represented by a few dozen living species. The order is currently divided into two major clades: Gonorynchoidei, which includes the families Gonorynchidae and Kneriidae, and Chanoidei, encompassing a single family, Chanidae, with a single recent species, the Indo-Pacific Chanos chanos, and several fossil taxa. Chanidae includes some poorly known taxa, such as Dastilbe moraesi, described from the Aptian (Lower Cretaceous) of the Areado Formation, Sanfranciscana basin, Brazil. This species is currently considered to be a junior synonym of the type species of its genus, Dastilbe crandalli, from Santana Formation, Aptian, northeastern Brazil. The analysis of abundant D. moraesi specimens revealed several new morphological features, many of which had previously been misinterpreted. Dastilbe moraesi was incorporated into a gonorynchiform character matrix as revised and modified for the Chanidae. We obtained a single most parsimonious tree in which D. moraesi is distinct and phylogenetically apart from D. crandalli. According our analysis, D. moraesi forms a sister pair with Chanos, a clade which is closely related to Tharrhias, all composing the tribe Chanini.

A large, freshwater chanid fish (Ostariophysi: Gonorynchiformes) from the Upper Cretaceous of MadagascarCitation for this article: Murray, A. M., Brinkman, D. B., Friedman, M., & Krause, D. W. (2023) A large, freshwater chanid fish (Ostariophysi: Gonorynchiformes) from the Upper Cretaceous of Madagascar. Journal of Vertebrate Paleontology . https://doi.org/10.1080/02724634.2023.2255630

“…4a) with the addition of †Parachanos. In our analysis, the large polytomy is positioned as the sister group to †Nanaichthys, and †Aethalionopsis is placed as sister to the polytomy plus †Nanaichthys, which is a reversal in positions of †Nanaichthys and †Aethalionopsis compared with the results of Ribeiro et al (2018). The 50% majority-rule consensus of the six most-parsimonious trees resolves most of the lineages of the polytomy and places †Vango within Chaninae in a polytomy with Chanini (Chanos + †Francischanos + †Tharrhias) and †Dastilbe (Fig.…”

“…9D). Ribeiro et al (2018) also recovered a clade consisting of †Rubiesichthys and †Gordichthys (= Rubiesichthyinae), but their Chaninae included †Aethalionopsis as well as †Nanaichthys, along with †Parachanos and †Dastilbe crandalli, with †Francischanos moraesi (as †Dastilbe moraesi in their analysis) forming the sister group to Chanos (Fig. 9E).…”

“…If we are correct that all these gonorynchiform elements represent a single species, then the placement of †Vango fahiny within the Chanidae is confirmed further by the anatomy of these other bones: the maxilla has a bulbous posterior margin, and preopercle has limbs forming a ≥ 90°angle. These features are all noted as diagnostic of the suborder Chanoidei and family Chanidae by Grande and Poyato-Ariza (1999) and Ribeiro et al (2018). Based on the shape of the preopercle (limbs not meeting at an acute angle) and maxilla (articular process robust and only slightly curved), these elements can be further assigned to the Chaninae, rather than the Rubiesichthyinae.…”

“…The final species, †D. moraesi, from Barremian or Aptian lacustrine deposits of Brazil (Ribeiro et al, 2018(Ribeiro et al, , 2022, has now been given its own genus as †Francischanos moraesi (Ribeiro et al, 2022). Therefore, of the species formerly in †Dastilbe, there remain only two, †D.…”

“…These Early Cretaceous taxa have been included in the suborder Chanoidei based on the phylogenetic analysis of Grande and Poyato-Ariza (1999), who assessed † Aethalionopsis , † Gordichthys , † Rubiesichthys , † Tharrhias , † Parachanos , and † Dastilbe . Ribeiro et al (2018) expanded this list to include † Nanaichthys , which they resolved as the sister taxon of all other members of Chaninae. † Caeus has been included in Chanoidei by the assignment of the taxon to the family Chanidae (Amaral & Brito, 2012; Taverne & Capasso, 2017), but it has not been included in a formal phylogenetic analysis.…”