taxonID	type	description	language	source
FF7087B35774FFF40493FE40FF28E872.taxon	description	PHALANX In the original description of P. martini Hoffstetter, 1961, the author mentions an ungual phalanx twice without figuring it. The first mention is in the description of the lot that corresponds to the holotype (‘ trois phalanges dont une ungueale’; [three phalanges, including one ungual]; Hoffstetter, 1961: 61). The second mention of the ungual phalanx, in the description itself, is written in the conditional tense, denoting the hesitation of the author regarding the attribution (Hoffstetter, 1961: 80). There, the author mentions the second digit of the manus. The description states that this phalanx is less compressed than in Hapalops, that the dorsal side is transversely rounded, the palmar side flattened, and that the ungual bears a weak proximodistal curvature. Since the publication of Hoffstetter (1961), the ungual phalanx of the second digit of the manus has been described in an additional nothrotheriid, Mionothropus (De Iuliis et al., 2011), and in Thalassocnus (Amson et al., 2015 a). It has already been emphasized that the semicircular cross-section of the ungual process of the second digit of the manus is a distinctive traits of nothrotheriids [McDonald & Muizon (2002), ch. 28; Muizon et al. (2003), ch. 30; De Iuliis et al. (2011), ch. 55] and of the early species of Thalassocnus, T. antiquus (the later species of the genus being characterized by a dorsopalmar flattening of this process; Amson et al., 2015 a), as this cross-sectional shape is not found in other digits or taxa. As the ungual process of the ungual phalanx of the holotype of P. martini features this distinctive cross-sectional shape, and hence strongly resembles those of nothrotheriids and of T. antiquus, we can today confirm Hoffstetter’s (1961) tentative attribution. Given the systematic importance of this phalanx (see below), an illustration is included herein (Fig. 9).	en	Amson, Eli, de Muizon, Christian, Gaudin, Timothy J. (2017): A reappraisal of the phylogeny of the Megatheria (Mammalia: Tardigrada), with an emphasis on the relationships of the Thalassocninae, the marine sloths. Zoological Journal of the Linnean Society 179: 217-236, DOI: 10.1111/zoj.12450, URL: https://doi.org/10.1111/zoj.12450
FF7087B35776FFE904B6FE27FE7FE879.taxon	description	OTHER RELATIONSHIPS AMONGST MEGATHERIOIDEA Although not the focus of the present study, some comments can be made regarding the other nodes of the tree produced by our analysis. As in previous phylogenetic analyses (Gaudin, 2004; Pujos et al., 2007; and references therein), the Megatheria, a clade comprising the megatheriids and the nothrotheriids, is recovered. Whereas this clade was supported by only four unambiguous synapomorphies in Gaudin (2004), seven unambiguous synapomorphies are obtained here (and up to 31 depending on the optimization). Only two of these are postcranial synapomorphies. This could suggest that the inclusion of Thalassocnus itself in an analysis that comprises both families of Megatheria further substantiates the recognition of this clade, although the modification of the taxonomic sample when compared to the analysis of Gaudin (2004) cannot be ruled out as an alternative cause of the increase of unambiguous synapomorphies for the Megatheria. Concerning their postcranium, the Megatheria are defined by the medially projecting bicipital tuberosity of the radius [ch. 6 (0) 1)] and the prominent anterior extension of the medial trochlear ridge of the femur [ch. 31 (1) 0)]. Furthermore, they are unambiguously defined by parallel lateral edges of the mandibular spout [ch. 133 (1) 0); CI = 1 / 2, RI = 3 / 4], a posterior external opening of mandibular canal that opens laterally on the horizontal ramus [ch. 136 (0) 1); nonhomoplastic], fused vomerine wings, leaving the overlying ethmoid unexposed [ch. 260 (0) 1); CI = 1 / 3, RI = 3 / 5], medial expansion of entotympanic dorsal to floor of basicranium [ch. 292 (1) 0); CI = 1 / 4, RI � 0.6], stylomastoid foramen connected to nearby ventral opening of canal for occipital artery by a strong groove [ch. 321 (1) 3); CI � 0.4, RI � 0.6], and occipital artery completely enclosed within a canal [ch. 331 (1) 3); CI = 0.3; RI � 0.7]. According to Gaudin (2004), the clade Megatherioidea includes the Megatheriidae, Nothrotheriidae, and a third family, the Megalonychidae (which comprises the extant two-toed sloth Choloepus), along with several Santacrucian taxa whose relationships are not entirely resolved, namely Schismotherium, Pelecyodon, Hapalops, and Analcimorphus. Our results yield an unambiguous resolution of the relationships amongst these early megatherioids and the three megatherioid families. Schismotherium and Pelecyodon form a clade that represents the sister group of all other Megatherioidea, herein called ‘ clade A’. This clade is not well supported (branch support value of 2), but it is noteworthy that it was also found in one of the MPTs of Gaudin (2004). It is defined by six unambiguous synapomorphies: upper and lower caniniforms (C 1 and c 1) slightly depressed ventrally relative to the remaining molariforms [ch. 64 (0) 2); CI = 1 / 2, RI = 3 / 5], elongate diastema [ch. 67 (0) 1); CI = 1 / 2, RI � 0.8], sphenopalatine foramen situated well anterior and ventral to sphenorbital fissure / optic foramen [ch. 222 (1) 0); CI = 1 / 3, RI � 0.7], squamosal with lateral bulge at root of zygoma [ch. 228 (0) 1); CI = 1 / 3, RI � 0.7], nuchal crest overhangs occiput posteriorly [ch. 245 (0) 1); nonhomoplastic], and rugose tympanic external surface [ch. 263 (0) 1); CI = 1 / 2, RI = 4 / 5]. Hapalops is positioned here as sister taxon of a clade consisting of Analcimorphus and megalonychids, all forming the ‘ clade B’ (Fig. 10). This clade is not well supported either (branch support value of 1), but was also recovered in some of the analyses of Gaudin (2004), depending on the character weighting scheme. The ‘ clade B’ is defined by seven unambiguous synapomorphies: no contact between lunar and unciform [ch. 12 (1) 0); CI = 1 / 2, RI = 1 / 2), median position of astragalar process for navicular in distal view [ch. 38 (1) 0); nonhomoplastic], 18 or more thoracic vertebrae [ch. 51 (1) 0); nonhomoplastic], elongate and narrow coronoid process of dentary [ch. 108 (2) 0); CI = 1 / 4, RI � 0.6], one posteriorly projecting point on distal portion of descending process of jugal [ch. 215 (1) 0); CI = 1 / 4, RI = 1 / 2], median ridge of occiput extends dorsally onto the roof of the skull [ch. 246 (0) 1); CI = 1 / 2, RI = 1 / 2], and occipital condyles with distinct neck [ch. 254 (0) 1); CI = 1 / 3, RI � 0.8]. The Nothrotheriidae are recovered as monophyletic and well supported (branch support value of 9), with 11 unambiguous synapomorphies, amongst them the presence of a contact between the pterygoid and the vomer [ch. 193 (0) 1); CI = 1 / 2, RI = 3 / 4], the vomer bearing an elongate asymmetrical ventral keel and extending posteriorly into nasopharynx [ch. 261 (0) 1), nonhomoplastic], and a very large exposure of the vomer, which covers the presphenoid and much of the basisphenoid [ch. 262 (0) 1), nonhomoplastic].	en	Amson, Eli, de Muizon, Christian, Gaudin, Timothy J. (2017): A reappraisal of the phylogeny of the Megatheria (Mammalia: Tardigrada), with an emphasis on the relationships of the Thalassocninae, the marine sloths. Zoological Journal of the Linnean Society 179: 217-236, DOI: 10.1111/zoj.12450, URL: https://doi.org/10.1111/zoj.12450
