Musankwa sanyatiensis, Barrett & Chapelle & Sciscio & Broderick & Zondo & Munyikwa & Choiniere, 2024

Barrett, Paul M., Chapelle, Kimberley E. J., Sciscio, Lara, Broderick, Timothy J., Zondo, Michel, Munyikwa, Darlington & Choiniere, Jonah N., 2024, A new Late Triassic sauropodomorph dinosaur from the Mid-Zambezi Basin, Zimbabwe, Acta Palaeontologica Polonica 69 (2), pp. 227-241 : 231-238

publication ID	https://doi.org/ 10.4202/app.01100.2023
persistent identifier	https://treatment.plazi.org/id/2D4387C3-DD74-FFFF-F4A7-FBF61FEA1714
treatment provided by	Felipe
scientific name	Musankwa sanyatiensis
status	sp. nov.

Treatment

Musankwa sanyatiensis sp. nov.

Figs. 1E View Fig , 2 View Fig , 3 View Fig .

ZooBank LCID: urn:lsid:zoobank.org:act:A0C7FA6C-0A14-40F1-97E1-621F99D81AE3

Etymology: Named for the Sanyati River, whose original course is now submerged in the Sanyati Basin of Lake Kariba, in which the type locality (Spurwing Island) is situated.

Holotype: NHMZ 2521 , a partial right hind limb, consisting of a complete femur, tibia, and astragalus, with associated indeterminate bone fragments.

Type locality: The “Spurwing East Palaeosol” site (16°43.592’S, 28°41.771’E; Fig. 1 View Fig ; see also Sciscio et al. 2021b), situated on the north-eastern shoreline of Spurwing Island , Lake Kariba, Zimbabwe (Mid-Zambezi Basin) GoogleMaps .

Type horizon: Pebbly Arkose Formation, Upper Karoo Group, Norian, Upper Triassic (see Barrett et al. 2020; Sciscio et al. 2021b).

Diagnosis.—Prominent posterior tubercle present on proximal margin of femur (also present in Eucnemesaurus , Riojasaurus , and Sefapanosaurus ); shaft of proximal femur anteroposteriorly expanded and swollen at the level of the anterior trochanter (also in Coloradisaurus , absent in other taxa); base of fourth trochanter straight, positioned centrally on the posterior surface of the femur, and situated entirely within the proximal half of the femur (unique character combination, absent from other taxa); fibular condyle of proximal tibia separated from the cnemial crest by a distinct sulcus (also in Coloradisaurus ).

Material.— Type material only.

Description.—The specimen described herein was discovered by one of us (PMB) during an expedition to the southern shore of Lake Kariba in March 2018 (see also Sciscio et al. 2021a; Barrett et al. 2023; Fig. 1A–C View Fig ). It was found weathering out on the surface with the preserved elements in articulation ( Fig. 1E View Fig ). The material is heavily sun-cracked and weathered, with poor surface preservation that might reflect a long period of surface exposure prior to collection, as well as pre-burial damage. No other vertebrate material was found in the immediate vicinity of the find. The holotype consists of a partial right leg ( Figs. 1E View Fig , 2 View Fig , 3 View Fig ) including a femur, tibia, and astragalus, all of which are largely complete, and small indeterminate bone fragments. The astragalus remains in articulation with the distal tibia. The tibia is shorter than the femur, reaching ~85% of the length of the latter. Measurements for all the elements are provided in Table 1. Based on the formula for inferring body mass for bipedal taxa using minimum femoral circumference (see Material and methods above), NHMZ 2521 has an estimated body mass of ~ 386 kg.

Femur: In anterior view, the femur is strongly sigmoidal in outline, with the shaft twisting laterally below the level of the proximal end, then strongly medially at midlength, and finally twisting laterally in its ventral-most part ( Fig. 2A View Fig 1 View Fig ). It is also subtly sigmoidal in lateral view, although the degree of twisting in this plane is much less pronounced, with the shaft bowing posteriorly just ventral to the dorsal end as well as distally, and bowing anteriorly in its dorsal-most and central parts ( Fig. 2A 2 View Fig ).

The head of the femur is oriented medially and slightly ventrally in anterior view ( Fig. 2A View Fig 1 View Fig ). It has a rounded, semicircular outline, but poor preservation makes interpretation of other features difficult. For example, there appears to be a distinct ligament groove on the anterior surface extending parallel to the medial margin of the process, but this could be the result of erosion or damage as there is no cortical bone in this area. The ventral margin of the femoral head is separated from the shaft by an angle of ~120° and the two surfaces grade into each other without an abrupt change in slope. In medial view, the head has a sub-oval outline that is broadest dorsally and tapers to a rounded apex ventrally ( Fig. 2A View Fig 4 View Fig ).

In anterior view, the greater trochanter is situated slightly dorsal to the level of the femoral head. Its lateral margin is gently curved and meets the dorsal surface at ~90°. Its dorsal margin forms a continuous straight line with that of the femoral head. The entire proximal end of the femur is twisted with respect to the shaft, so that the femoral head projects strongly anteromedially, a feature best observed in proximal view. Overall, in proximal view, the dorsal surface of the femur has a sub-elliptical outline that is anteroposteriorly expanded in its central part (at the level of the posterior tubercle) and tapers laterally and medially, with the femoral head exhibiting greater expansion than the greater trochanter ( Fig. 2A View Fig 5). The dorsal surfaces of the femoral head and greater trochanter are confluent and there is no fossa trochantericus. This combined surface is gently convex both anteroposteriorly and mediolaterally, and appears to have been strongly rugose. An elliptical boss, with its long axis extending dorsomedially–anterolaterally, is positioned in the central part of the posterior surface of the proximal end, confluent with its proximal margin, and likely represents the posterior proximal tubercle ( Fig. 2A View Fig 1 View Fig , A 5).

A prominent, raised ridge on the anterior surface of the proximal end represents the lesser trochanter ( Fig. 2A View Fig 3 View Fig ). It is situated centrally, equally distanced from the medial and lateral shaft margins. Consequently, it is not visible in posterior view. Although its dorsal apex is eroded, the remaining part indicates that it terminated well below the level of the femoral head. The process extends for a considerable distance ventrally, merging into the shaft at a point approximately 36% of the distance from the femoral dorsal margin and it extends for at least ~22% of total femoral length. The lesser trochanter is so prominent, being approximately as high as it is wide, that it imparts a strongly triangular, swollen cross-section to the proximal part of the femoral shaft ( Fig. 2A 2 View Fig , A 4 View Fig ).

The broken base of the fourth trochanter is a prominent feature positioned on the posterior surface of the shaft, slightly offset towards its medial margin ( Fig. 2A View Fig 1 View Fig ). It has an elongate, elliptical outline whose long axis extends dorsoventrally. Its ventral margin is situated well above femoral midlength (and ventral to the ventral-most extent of the lesser trochanter) at around 42% of total femoral length. As broken, it is not possible to determine the shape or extent of the process. The shaft transverse cross-section ventral to the fourth trochanter is elliptical, with its longest axis oriented mediolaterally.

In anterior view, the ventral part of the femur is expanded mediolaterally with respect to the shaft, but this expansion is asymmetrical and occurs solely on its lateral side ( Fig. 2A View Fig 3 View Fig ). Consequently, the medial margin of the ventral end is gently convex, forming an angle of around 90° with the femoral ventral margin, whereas the corresponding lateral margin is concave and forms an angle of around 70° with the ventral margin. Its anterior surface is flat to gently convex and lacks any fossae or ridges. The ventral margin is straight and oriented horizontally. The lateral condyle projects strictly posteriorly in both lateral and posterior views. It is shorter anteroposteriorly than it is either tall dorsoventrally or wide mediolaterally and has a sub-circular outline in posterior view, although this has likely been altered by weathering. It is separated from the medial condyle by a wide, shallow intercondylar groove. The broken base of the medial condyle indicates that it was considerably larger than the lateral condyle in both width and height, but no other details can be determined. In distal view, the preserved part of the ventral end has a sub-rectangular outline and is concave mediolaterally, but this area has been altered by damage ( Fig. 2A View Fig 6).

Tibia: The dorsal and ventral ends of the tibia are expanded with respect to the slender elongate shaft ( Fig. 2B View Fig 1 –B View Fig 4 View Fig ). The dorsal expansion has its long axis oriented anteroposteriorly; by contrast, the ventral expansion has undergone torsion and its long axis is oriented anterolaterally-posteromedially, and this is offset by ~40–50° from that of the dorsal end.

In proximal view, the dorsal end is rugose and has a sub-triangular outline, with the apices of this triangle formed by the cnemial crest anteriorly, the fibular crest laterally, and the posterior process ( Fig. 2B View Fig 5). The dorsal surface is anteroposteriorly convex but mediolaterally concave, so that it is very subtly “saddle-shaped”. The cnemial crest is narrow and triangular in outline, being slightly longer than wide. Its apex is oriented anteriorly and very slightly laterally and has a blunt, rounded terminus. The cnemial crest is separated from the fibular condyle by a broad, open notch, which forms an angle of ~160° between the two processes. The fibular condyle has an elongate, elliptical outline that is more than twice as long as it is broad. The posterior margin of the fibular condyle meets the posterior process at an angle of ~120° forming a clearly differentiated notch between them. The posterior process has a squat, equilateral triangle-shaped outline whose apex projects posteriorly. In proximal view, the medial margin of the dorsal end describes a shallow, smoothly convex curve in contrast to the strongly sinuous lateral margin ( Fig. 2B View Fig 5).

The dorsal end of the tibia is strongly expanded anteroposteriorly with respect to the shaft, with this expansion being almost symmetrical in either lateral or medial view ( Fig. 2B 2 View Fig , B 4 View Fig ). The cnemial crest extends for only a short distance along the anterior margin of the shaft, accounting for 18% of total tibial length, and gives the dorsal expansion a gently convex anterior margin. By contrast, the posteroventral margin of the posterior process has a more acute outline ( Fig. 2B 2 View Fig , B 4 View Fig ). The medial surface of the dorsal expansion is anteroposteriorly convex. In lateral view, the fibular condyle is supported by a stout buttress, delimited anteriorly and posteriorly by broad grooves confluent with the notches on the dorsal surface (see above), which extends for a short distance ventrally before merging into the shaft ( Fig. 2B 2 View Fig ). The tibial shaft has a sub-circular transverse cross-section that is slightly wider mediolaterally than long anteroposteriorly.

The ventral surface of the tibia is obscured by the astragalus but is visible in our µCT segmentations. It has a sub-rectangular outline, which was longer anterolaterally-posteromedially than perpendicular to this ( Figs. 2B 2 View Fig , B 3, 3A, B View Fig ). The anterior and posterior descending processes are almost identical in anterolateral-posteromedial width, but the posterior descending process extends further ventrally, creating a distinct, anterolaterally directed notch for the reception of the ascending process of the astragalus ( Fig. 3B View Fig ). The anteromedially facing surface of the ventral expansion is the broadest and is shallowly concave, the narrow anterolaterally facing surface is flat, and the posteromedial and posterolateral surfaces merge into each other to form a smooth, rounded surface.

Astragalus: The astragalus is tightly appressed to the tibia, obscuring its dorsal surface, although this is visible in the µCT scans (see SOM 1 and 2). In anterior view, it has a sub-trapezoidal outline, whose ventral and dorsal margins are subequal in length and approximately 3.2 times longer than its medial margin is tall ( Fig. 3C View Fig 1 View Fig ). The medial margin is gently convex, while all of the other margins are concave. The astragalus is dorsoventrally tallest laterally as it includes a prominent, triangular ascending process that articulates with the notch on the distal tibia ( Fig. 3C View Fig 1 View Fig , C 2 View Fig ). In anterior view, the base of the ascending process is slightly wider than it is tall. It is inset from the lateral margin of the astragalar body by a distinct notch. The lateral margin of the ascending process is oriented almost vertically and is slightly concave, whereas the medial margin slopes ventrally from the apex of the process at an angle of approximately 30º below the horizonal. A foramen is present on the anterior surface of the astragalus ventral to the ascending process, but is not set within a distinct fossa ( Fig. 3C View Fig 1 View Fig ).

Most of the dorsal surface medial to the ascending process forms a large, ovate, shallowly concave articular facet for the reception of the tibia ( Fig. 3C 3 View Fig , C 5). This facet is anteroposteriorly broadest medially and tapers laterally as it merges with the medial surface of the ascending process. The tibial facet is inclined so that it faces posterodorsally and is highest anteriorly in medial view, while its posterior margin is formed by a slightly upturned lip. The medial slope of the ascending process is broad (accounting for approximately half of the anteroposterior length of the astragalus) and forms a planar smooth surface. This process has a triangular transverse cross-section. A distinct break-of-slope is present between the articular facet and a deep concavity that excavates the posterior margin of the ascending process.

In medial view, the astragalus has a sub-crescentic outline and the anterior, ventral, and posterior margins form a continuous convex curve ( Fig. 3C View Fig 4 View Fig ). Its dorsal margin is concave for the reception of the tibia and the lateral surface is convex both anteroposteriorly and dorsoventrally. In ventral view, its articular surface is sub-rectangular in outline and its posterolateroventral corner appears to be damaged. The ventral surface is roller-like and strongly convex anteroposteriorly ( Fig. 3C View Fig 6).

Posteriorly, the main body of the astragalus is tallest medially and tapers laterally, due to lateromedial sloping of its dorsal surface ( Fig. 3C 3 View Fig ). The posterior margin of the ascending process is buttressed by a stout, vertical, robust ridge. Medial to this ridge the posteromedial margin of the process is excavated by a deep concavity.

Other material: A small part of the distal fibula was originally present ( Fig. 1E View Fig ) but was so poorly-preserved it did not survive collection and preparation. Several other small bone fragments were collected from around the articulated specimen, but none of these can be matched with existing breaks or have sufficient morphology to be identified further.

Remarks.— Musankwa sanyatiensis gen. et sp. nov. can be distinguished from other Late Triassic massopodan taxa on the basis of numerous hind limb characteristics. For example, the femora of Coloradisaurus brevis Bonaparte, 1978 ( Apaldetti et al. 2013), Kholumolumo ellenbergerorum Peyre de Fabrègues & Allain, 2020 ( Peyre de Fabrègues and Allain 2020), Macrocollum itaquii Müller et al., 2018 ( Müller et al. 2018), Meroktenos thabanensis ( Gauffre, 1993) ( Peyre de Fabrègues and Allain 2016) , Mussaurus patagonicus Bonaparte & Vince, 1979 ( Otero and Pol 2013), and Riojasaurus incertus Bonaparte, 1971 (PVL 3808; Bonaparte 1971) are straight in anterior view, lacking the marked sigmoidal curvature present in Musankwa sanyatiensis . The femur of Eucnemesaurus entaxonis McPhee et al., 2015 , has an intermediate condition where it is curved in its proximal part but straight distally (BP/1/6234; McPhee et al. 2015) and the partial proximal femora of Sefapanosaurus zastronensis Otero et al., 2015 , are straight (BP/1/7440, 7441, 7442; Otero et al. 2015), differing from the strongly sigmoidal profile in Musanwka sanyatiensis . However, moderately sigmoidal femora are present in Plateosauravus cullingworthi Haughton, 1924 ( Haughton 1924). The ratios of tibia/femur total length also vary among these taxa, but comparative statements are difficult due to either breakage, specimen incompleteness, or lack of definitive association. Where available these range from 0.73 in Mussaurus patagonicus ( Otero and Pol 2013) through 0.85 in Musankwa sanyatiensis ( Table 1) and Riojasaurus incertus ( Bonaparte 1971) , 0.87 in Coloradisaurus brevis ( Apaldetti et al. 2013) and ~ 0.9 in Macrocollum itaquii ( Müller et al. 2018) .

A prominent posterior tubercle is present on the proximal femur in Musankwa sanyatiensis , Eucnemesaurus fortis Van Hoepen, 1920 (BP/1/6111; Yates 2007), Eucnemesaurus entaxonis (BP/1/6234; McPhee et al. 2015), and Riojasaurus incertus (PVL 3808), is variably present in Sefapanosaurus zastronensis (present in BP/1/7441 and 7442 and absent in BP/1/7440; contra Otero et al. 2015), and absent in Coloradisaurus brevis ( Apaldetti et al. 2013) , Kholumolumo ellenbergerorum ( Peyre de Fabrègues and Allain 2016) , Meroktenos thabanensis ( Peyre de Fabrègues and Allain 2020) , and Mussaurus patagonicus ( Otero and Pol 2013) . In Musankwa sanyatiensis and Coloradisaurus brevis ( Apaldetti et al. 2013) , the area supporting the lesser trochanter is inflated anteroposteriorly, creating a distinctive bulging of this area in lateral or medial view, and the ratio of femoral anteroposterior diameter in this region (at the base of the lesser trochanter) to femoral length is 0.15 in both taxa. This compares with the more anteroposteriorly compressed femora of Eucnemesaurus entaxonis (BP/1/6234; 0.11), Kholumolumo ellenbergerorum ( Peyre de Fabrègues and Allain 2020; 0.10), Meroktenos thabanensis ( Peyre de Fabrègues and Allain 2016; 0.10), Mussaurus patagonicus ( Otero and Pol 2013; 0.10), and Riojasaurus incertus (PVL 3808; 0.11), which lack this bulge. Although it is not possible to calculate this ratio in Eucnemesaurus fortis and Sefapanosaurus zastronensis due to incompleteness (BP/1/6111, Yates 2007; BP/1/7440–7442, Otero and Pol 2013), or in Macrocollum itaquii due to a lack of published measurements ( Müller et al. 2018), these specimens also lack the distinct swollen area present in Musankwa sanyatiensis and Coloradisaurus brevis .

In Kholumolumo ellenbergerorum ( Peyre de Fabrègues and Allain 2020) , Meroktenos thabanensis ( Peyre de Fabrègues and Allain 2016) , and Plateosauravus cullingworthi ( Haughton 1924) the ventral part of the fourth trochanter extends onto the distal half of the femoral shaft, whereas in Coloradisaurus brevis ( Apaldetti et al. 2013) , Eucnemesaurus entaxonis (BP/1/6234; McPhee et al. 2015), Macrocollum itaquii ( Müller et al. 2018) , Musankwa sanyatiensis , Mussaurus patagonicus ( Otero and Pol 2013) , and Riojasaurus incertus (PVL 3808; Bonaparte 1971) this process is confined to its proximal half. Furthermore, the base of the fourth trochanter is inset from the medial margin of the femur in Musankwa sanyatiensis to lie almost centrally on the shaft, as in Kholumolumo ellenbergerorum ( Peyre de Fabrègues and Allain 2020) and Plateosauravus cullingworthi ( Haughton 1924) , whereas it is medially displaced in Coloradisaurus brevis ( Apaldetti et al. 2013) , Eucnemesaurus entaxonis (BP/1/6234; McPhee et al. 2015), Eucnemesaurus fortis (BP/1/6111; Yates 2007), Meroktenos thabanensis Peyre de Fabrègues and Allain 2016 ), Mussaurus patagonicus ( Otero and Pol 2013) , and Riojasaurus incertus (PVL 3808; Bonaparte 1971). In addition, the base of the fourth trochanter in Coloradisaurus brevis ( Apaldetti et al. 2013) , Musankwa sanyatiensis , Kholumolumo ellenbergerorum Peyre de Fabrègues and Allain 2020 ), and Mussaurus patagonicus ( Otero and Pol 2013) is almost vertically inclined and straight, whereas in Eucnemesaurus fortis (BP/1/6111; Yates 2007), Eucnemesaurus entaxonis (BP/1/6234; McPhee et al. 2015), Meroktenos thabanensis ( Peyre de Fabrègues and Allain 2016) , and Riojasaurus incertus (PVL 3808) the base is obliquely inclined, trending proximomedially– distolaterally, and often curved or kinked along its length. In Plateosauravus cullingworthi the base of the trochanter is curved, but its long axis is more vertically inclined Haughton 1924).

In distal view, the lateral margin of the femur bears a shallow sulcus in Musankwa sanyatiensis and Meroktenos thabanensis ( Peyre de Fabrègues and Allain 2016) . A similarly positioned but deeper sulcus is present in Coloradisaurus brevis ( Apaldetti et al. 2013) , Eucnemesaurus fortis (BP/1/6111; Yates 2007), and Riojasaurus incertus (PVL 3808), but this feature is absent in Kholumolumo ellenbergerorum ( Peyre de Fabrègues and Allain 2020) .

The ratio between the maximum anteroposterior length of the proximal end of the tibia and overall tibia length varies among Late Triassic sauropodomorph taxa, from the most slender in Jaklapallisaurus asymmetricus Novas et al., 2011 (0.24, Ezcurra et al. 2023), though intermediate values in Coloradisaurus brevis (0.29, Apaldetti et al. 2013), Eucnemesaurus fortis (0.33, Van Hoepen 1920), Kholumolumo ellenbergerorum , Musankwa sanyatiensis , Mussaurus patagonicus , Riojasaurus incertus (0.38, in all taxa, measurements from Peyre de Fabrègues and Allain 2020, Table 1, Otero and Pol 2013, PVL 3808, respectively), Plateosauravus cullingworthi (0.40, Haughton 1924), and Melanorosaurus readi Haughton, 1924 (0.43, SAM-PK-3449; Haughton 1924), to the stockiest in Blikanasaurus cromptoni Galton & Van Heerden, 1985 (0.48, Galton and Van Heerden 1985).

In Musankwa sanyatiensis , the proximal end of the tibia has a maximum length/maximum width ratio of 1.65, which compares with the slightly more elongate proximal tibiae of Blikanasaurus cromptoni (1.75, SAM-PK-K403), Kholumolumo ellenbergerorum (1.72, Peyre de Fabrègues and Allain 2020), Melanorosaurus readi (1.68, SAM-PK-3449), Plateosauravus cullingworthi (1.77, Haughton 1924), Riojasaurus incertus (1.75, PVL 3808), and Sefapanosaurus zastronensis (1.85, BP/1/7445; Otero et al. 2015), and the stouter tibiae of Jaklapallisaurus asymmetricus (1.32, Ezcurra et al. 2023) and Eucnemesaurus fortis (1.51, Van Hoepen 1920). In addition, the fibular condyle of the tibia is a distinct process that is separated from the cnemial crest (and often the posterior process also) by a distinct sulcus or notch in Macrocollum itaquii ( Müller et al. 2018) , Musankwa sanyatiensis , and Coloradisaurus brevis ( Apaldetti et al. 2013) , whereas these sulci are either incipient or absent in Blikanasaurus cromptoni (SAM-PK-K403), Eucnemesaurus fortis (BP/1/6111; Yates 2007), Jaklapallisaurus asymmetricus ( Ezcurra et al. 2023) , Melanorosaurus readi (SAM-PK-3449), Mussaurus patagonicus ( Otero and Pol 2013) , Riojasaurus incertus (PVL 3808), and Sefapanosaurus zastronensis (BP/1/7445; Otero et al. 2015).

The cnemial crest of Musankwa sanyatiensis accounts for 23% of tibial length, as in Macrocollum itaquii ( Müller et al. 2018) , Coloradisaurus brevis ( Apaldetti et al. 2013) , and Mussaurus patagonicus ( Otero and Pol 2013) , whereas longer crests are present in Blikanasaurus cromptoni (31%, SAM-PK-K403; Galton and Van Heerden 1985), Eucnemesaurus fortis (29%, Van Hoepen 1920), Melanorosaurus readi (27%, SAM-PK-3449), and Riojasaurus incertus (31%, PVL 3808), with shorter crests in Jaklapallisaurus asymmetricus (19%, Ezcurra et al. 2023) and Kholumolumo ellenbergerorum (20%, Peyre de Fabrègues and Allain 2020). Musankwa sanyatiensis lacks the distinct intramuscular line that extends along the anterior surface of the distal tibial shaft in Unaysaurus tolentinoi Leal et al., 2004 ( McPhee et al. 2020).

Blikanasaurus cromptoni ( Galton and Van Heerden 1985) and Mussaurus patagonicus ( Otero and Pol 2013) lack the foramen that is situated ventral to the base of the ascending process in Musankwa sanyatiensis , Coloradisaurus brevis ( Apaldetti et al. 2013) , Riojasaurus incertus (PVL 3808), Unaysaurus tolentinoi ( McPhee et al. 2020) , and many other early-diverging sauropodomorphs. The astragalus of Musankwa sanyatiensis lacks the diagnostic T-shaped ascending process of Sefapanosaurus zastronensis (BP/1/386; Otero et al. 2015). A distinct, deep concavity on the posteromedial surface of the ascending process is present in Coloradisaurus brevis ( Apaldetti et al. 2013) , Musankwa sanyatiensis , and Riojasaurus incertus ( Novas 1989) , but is absent in Blikanasaurus cromptoni ( Galton and Van Heerden 1998) and Mussaurus patagonicus ( Otero and Pol 2013) . A prominent anteromedial process extends from the astragali of Jaklapallisaurus asymmetricus ( Ezcurra et al. 2023) , Macrocollum itaquii ( Ezcurra et al. 2023) , and Unaysaurus tolentinoi ( McPhee et al. 2020) but is absent in Musankwa sanyatiensis and most other sauropodomorphs.

Although Musankwa sanyatiensis possesses no autapomorphies, which is perhaps unsurprising given the limited material available, the foregoing comparisons demonstrate that it can be distinguished from other Late Triassic massopodans, including all of its southern African contemporaries, on the basis of a unique character combination (see Diagnosis, above).

Stratigraphic and geographic range.— Type horizon and locality only.

1920