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McDonald et al. (2010) proposed that an isolated, nearly complete dentary of large size with two embedded dentary crowns (NHMUK OR28660), collected from one of the quarries at Whiteman’s Green, Cuckfield, can be diagnosed as a new taxon of Valanginian neoiguanodontian: Kukufeldia tilgatensis McDonald, Barrett, and Chapman, 2010. This specimen is of considerable historical interest, because it was first studied and described by Mantell (1848) and later by Owen (1855). Their diagnosis currently rests upon one character: an apparently unique pattern of vascular foramina on the outer surface near the anterior tip of the jaw, and this is supported by some subsidiary evidence concerning the comparative straightness of the anterior part of the dentary ramus. The distribution of vascular foramina on the external surface of the dentary is a character of dubious validity, given the variation in the pattern of vascular openings that may be seen between the left and right jaws of single individuals, let alone that which may be seen in different individuals (pers. obs.).

Apart from the pattern of dentary foramina, the distinction concerning the straightness of the dentary ramus relies upon an alleged association of another partial skeleton (NHMUK R1834) to the taxon B. dawsoni. The latter includes the anterior portion of an eroded dentary that appears to be arched, rather than straight. Unfortunately, NHMUK R1834 was incorrectly assigned to the taxon B. dawsoni by McDonald et al. (2010); it can be referred, quite unambiguously (Norman, 2010, in press), to the Valanginian taxon Hypselospinus fittoni (Lydekker, 1889) on the basis of detailed shared similarities between the ilium of the holotype of H. fittoni and that of NHMUK R1834 (Norman, in press). At present, K. tilgatensis comprises just the dentary of a large neoiguanodontian that is considered to be a nomen dubium and to be potentially referable to the contemporary large, robust neoiguanodontian taxon Barilium dawsoni. Furthermore, the dentary teeth are very similar in form to those of NHMUK R2358, which have been referred to B. dawsoni. Carpenter and Ishida (2010) proposed, in October of that year, a new taxonomic combination Torilion dawsoni (Fig. 2.2) for the holotype material named Iguanodon dawsoni; this proposal can be suppressed, because it is a junior objective synonym of Barilium dawsoni (Lydekker, 1888). Furthermore, Carpenter and Ishida proposed a new genus and species (Sellacoxa pauli) on the basis of a photograph of the right side of a large partial skeleton (NHMUK R3788) collected by Charles Dawson from Old Roar Quarry, near Hastings (Norman, 2011a). Naish and Martill (2008), using appropriately cautious remarks, suggested that its anatomy was unusual and perhaps indicative of a new species. The description by Carpenter and Ishida (2010) is erroneous (Norman, 2011a, 2011b) because these authors had evidently not examined the specimen closely and therefore failed to recognize preservational anomalies, missing pieces, or additional anatomical features visible on the other (left) side of the specimen (Norman, 2011a). Sellacoxa pauli (NHMUK R3788) is considered to be a nomen dubium (its diagnosis is incorrect), and this articulated partial skeleton is considered to be referable to the hypodigm of B. dawsoni (as originally argued by Norman, 1977, 2010, 2011a; Blows, 1998). The taxon Sellacoxa pauli Carpenter and Ishida, 2010, has been proposed to be a nomen dubium and that it can be relegated into synonym with Barilium dawsoni (Norman, 2011a; Fig. 2.2).

2.3. Barilium dawsoni. Preliminary skeletal reconstruction based upon the holotype and referred material (from Norman, 2011a).