The glaucous gull (L. hyperboreus) is, on average, somewhat smaller than the black-back but has been weighed at as much as 2.7 kg (6.0 lb).[11][31] Among the most prominent family of "small waders", the sandpipers reach their maximum size in the Far Eastern curlew (Numenius madagascariensis) at up to 0.66 and 1.1 m (2.2 and 3.6 ft) across the wings, although the more widespread Eurasian curlew (N. arquata) can weigh up to 1.36 kg (3.0 lb).[32][33] Less variable in size, the plovers largest species is the Australasian masked lapwing (Vanellus miles) at up to 0.4 m (1.3 ft) long, a 0.85 m (2.8 ft) wingspan and a weight of 400 g (14 oz).[34] The terns, previously considered members of the gull family, are usually slender and dainty-looking in comparisonm but the largest species, the widely distributed Caspian tern (Hydroprogne caspia), is quite large and heavily built.