Bellulia rectusunguis, Wang & Zhou & Zhou, 2016

Wang, Min, Zhou, Zhonghe & Zhou, Shuang, 2016, A new basal ornithuromorph bird (Aves: Ornithothoraces) from the Early Cretaceous of China with implication for morphology of early Ornithuromorpha, Zoological Journal of the Linnean Society 176 (1), pp. 207-223 : 208-209

Bellulia rectusunguis SP. NOV.

Holotype: IVPP V17970 , a nearly complete and articulated skeleton with an aggregate of gastroliths in the abdominal region and feather traces preserved in a single slab, missing the skull ( Figs 1 , 2 ; Table 1).

Etymology: Species name is derived from the Latin words ‘rectus’ (straight) and ‘unguis’ (claw), referring to the barely curved manual claws characterizing this taxon.

Locality and horizon: Jianchang County, Liaoning Province, northeastern China; Lower Cretaceous, Jiufotang Formation ( He et al., 2004).

Diagnosis: A large basal ornithuromorph bird that can be distinguished from other ornithuromorphs by the unique combination of the following features: V-shaped furcula with a short hypocleidium; sternum bearing elongated lateral trabecula with fan-shaped distal expansion; broad cranial margin of sternum with obtuse angle defined by coracoidal sulci of 113°; manual claws nearly straight; proximal ends of metatarsals II– IV coplanar; metatarsal IV robust (autapomorphy); hallucal ungual reduced; and intermebral index (humerus + ulna + carpometacarpus/

femur + tibiotarsus + tarsometatarsus) of 1.21.

Figures

Figure 1. Photograph of the holotype of Bellulia rectusunguis gen. et sp. nov., IVPP V17970. Scale bar, 20 mm.

Figure 2. Interpretive line drawing of the holotype of Bellulia rectusunguis gen. et sp. nov., IVPP V17970. Abbreviations: ca, caudal vertebra; co, coracoid; cv, cervical vertebra; dr, dorsal rib; d I–IV, digit I–IV; fe, femur; fi, fibula; fu, furcula; ga, gastroliths; ha, haemal arch; hu, humerus; il, ilium; is, ischium; ma, manus; mt I, metatarsal I; pr, primary remiges; py, pygostyle; ra, radius; re, rectrices; rr, radiale; sc, scapula; sr, sternal rib; st, sternum; sy, synsacrum; ta, tarsometatarsus; ti, tibiotarsus; tv, thoracic vertebra; ul, ulna; ur, ulnare. Scale bar, 20 mm.