Hippoporina miocenica was named by Gordon et al. (1994) [Colony erect, rod-like, branching, the branch diameter in the unique fragment up to 1.62 mm. Zooids evidently 9-10-serial, rectangular, nearly parallel sided. 1.02-1.25 mm long and 0.28-0.51 mm wide, with relatively thick raised margins. Orifice subcircular with scarcely any differentiation between anter and poster, condyles are not evident. No oral spines. Frontal shield somewhat sunken, evenly perforated by about 20-31 pores of which a proximal pair and a pair subjacent to the orifice appear to be areolar. Avicularia occasional, proximal to the orifice, relatively large, the rostrum somewhat elevated, acute, a cross-bar not apparent. Ovicells unknown.]. It is not extant. Its type specimen is H-598 (a single colony fragment). Its type locality is Kaipuke Siltstone/Anatori River mouth, which is in an Otaian transition zone/lower shoreface siltstone in the Kaipuke Siltstone Formation of New Zealand.