Macropodiformes Kirsch et al., 1997

Beck, Robin M. D., Voss, Robert S. & Jansa, Sharon A., 2022, Craniodental Morphology And Phylogeny Of Marsupials, Bulletin of the American Museum of Natural History 2022 (457), pp. 1-353 : 248-249

Macropodiformes Kirsch et al., 1997

CONTENTS: † Balbaridae , † Ekaltadeta , Hypsiprymnodontidae , Macropodidae , and Potoroidae .

STEM AGE: 33.0 Mya (95% HPD: 29.3–37.7 Mya).

CROWN AGE: 27.7 Mya (95% HPD: 23.6–32.1 Mya).

UNAMBIGUOUS CRANIODENTAL SYNAPOMORPHIES: Lacrimal exposure with one or more distinct tubercles (char. 8: 0→1; ci = 0.118); maxillary and frontal bones in contact on medial orbital wall (char. 13 0→1; ci = 0.143); maxillary and alisphenoid in contact on orbital floor (char. 16: 0→1; ci = 0.250); frontal and squamosal in contact on lateral aspect of braincase (char. 26: 0→1; ci = 0.071); palatine fenestrae present (char. 38: 0→1; ci = 0.071); pterygoid fossa large, deeply excavated, enclosed laterally by an ectopterygoid crest (char. 49: 0→1; ci = 0.143); masseteric fossa perforated by a masseteric canal (char. 99: 1→2; ci = 0.333); first upper premolar (P1) absent (char. 114: 0→1; ci = 0.200); sectorial P3 with well-developed ridges extending from apex to base of crown (char. 126: 1→2; ci = 0.154); major crest of semi- or fully sectorial P3 oriented posterolingual to anterolabial (char. 127: 1→0; ci = 0.400); and P3 erupts before M4 but after M3 (char. 130: 4→2; ci = 0.089).

COMMENTS: We follow den Boer and Kear (2018) in using Macropodoidea to refer to the crown clade (as defined by the extant families Macropodidae , Potoroidae , and Hypsiprymnodontidae ), and Macropodiformes for the total clade, that is to say, the clade comprising macropodoids plus all fossil taxa more closely related to macropodoids than to other extant phalangeridans. Our dated total-evidence analysis ( fig. 33) does not resolve whether balbarids and † Ekaltadeta fall within Macropodoidea or not, so the unambiguous craniodental synapomorphies identified here apply to Macropodiformes as a whole. Of the craniodental features that optimize as unambiguous synapomorphies, perhaps the most striking is the presence of a masseteric canal perforating the masseteric fossa, a feature that does not occur in any other known metatherian (char. 99; see also Abbie, 1939; Pearson, 1950; Ride, 1959; Woods, 1960; Archer, 1984c; Case, 1984; Flannery, 1984, 1987; Clemens et al., 1989; Warburton, 2009).

Our undated total-evidence analysis (fig. 32) places † Ekaltadeta sister to Hypsiprymnodon , and the balbarids † Balbaroo and † Ganawayamaya in a macropodid clade with † Ganguroo (a “bulungamayine” [= probable stem] macropodid; Prideaux and Warburton, 2010; Travouillon et al., 2014b; Cooke et al., 2015), † Hadronomas and † Rhizosthenurus (both plesiomorphic sthenurines; Murray, 1991, 1995; Kear and Cooke, 2001; Kear, 2002; Kirkham, 2004; Prideaux, 2004; Prideaux and Warburton, 2010), Dorcopsis , and Dorcopsulus . Our dated total-evidence topology ( fig. 33) is markedly different, although this is partly the result of topological constraints used to implement node calibrations within Macropodoidea (see Methods and appendix 2). In this reconstruction, there is a polytomy at the base of Macropodoidea, comprising † Ekaltadeta , † Balbaridae , Hypsiprymnodontidae (= Hypsiprymnodon moschatus + H. † bartholomaii ), and Macropodidae + Potoroidae , whereas † Ganguroo , † Hadronomas , and † Rhizosthenurus are placed as stem macropodids, with † Hadronomas and † Rhizosthenurus forming a sthenurine clade. In effect, the dated toplogy is far more similar to other recent published morphological and totalevidence analyses of macropodiform phylogeny that have included some or all of these taxa ( Kear et al., 2007; Kear and Pledge, 2008; Prideaux and Warburton, 2010; Prideaux and Tedford, 2012; Black et al., 2014c; Llamas et al., 2015: supplementary material; Travouillon et al., 2014b, 2015 a, 2016, 2022; Cooke et al., 2015; Butler et al., 2016, 2018; Cascini et al., 2019). We therefore focus on our dated topology when discussing subclades within Macropodoidea (see below).

The oldest known macropodiforms are from the late Oligocene of Australia ( Flannery et al., 1983; Flannery and Rich, 1986; Woodburne et al., 1994; Cooke, 1997 a, 2006; Cooke and Kear, 1999; Long et al., 2002; Kear et al., 2007; Kear and Pledge, 2008; Black et al., 2012b, 2014c; Travouillon et al., 2014b, 2015 a, 2016; Butler et al., 2016, 2018; den Boer and Kear, 2018). These fossils include at least one probable nonmacropodoid († Palaeopotorous priscus ; see den Boer and Kear, 2018); possible macropodoids (e.g., undescribed species of Hypsiprymnodon from Faunal Zone A at Riversleigh; Archer et al., 2006; Black et al., 2012b; Butler et al., 2017); and † Gumardee , which may be a potoroid ( Travouillon et al., 2016; but see Butler et al., 2016, 2018; Travouillon et al., 2022).