Rosa omeiensis and
Rosa sericea each have a form
'Pteracantha.' Distinguishing the two requires careful examination of the plant details because they have many characters in common.
Rosa omeiensis can grow to be twice as large as
Rosa sericea. The hips of
Rosa omeiensis can be deep red or yellow, obovoid or, if you're lucky, piriform (pear-shaped) and even two-toned. Most uniquely, the long fleshy yellow pedicel grows right out of the cane, tapering to a 6 - 20 (¼-¾ inch) mm fleshy hip.
Rosa omeiensis most commonly has 9 to 13 leaflets, although it can have as few as 5 and as many as 17. The native range of the two species overlap in the mountains, with
Rosa omeiensis also found at lower altitudes. See
References. Outstanding pictures of the hips can be found at the
Harvard University Herbarium, Plants and Fungi from the Hengduan Mountains and adjacent areas of south-central China. 
