Orifice ring absent or inconspicuous (rarely formed by papillae, but not as a contiguous ring); calyx tube 2-5 cm, slightly or not at all constricted at throat.

• 孔环无或不明显(很少通过乳突形，但不是作为一枚邻接的环)；萼筒2-5厘米，稍或完全不缢缩的在喉部。(34