The genera Heraldia is in the ‘Flag-tail Pipefishes’ evolutionary group (clade).  Kuiter (2000, 2003) separate the flag-tail group of pipefishes into a separate sub-family (Doryrhamphinae). The Flag-tail Pipefishes are group includes 20 described species in four genera; the Maroubra (2 species, Whitley 1948), Doryrhampus sp. (11 species, Kaup 1856), Dunckerocampus (6 described species and two proposed species, Whitley 1933), Heraldia (1 species and one proposed species, Paxton 1975).  In the terms of phylogenetic evolution the Flag-tail Pipefishes are a branch clade – see ancestry - at the first primary division of the syngnathids. The ‘Flag-tail pipefishes’ are free swimming except for Maroubra spp. They are not sexually dimorphic and the male broods 50-100 moderately sized eggs under the tail. From appearance there are quite a few undescribed species, particularly of Doryrhampus.  However, these cannot be distinguished through taxonomy of preserved specimens.  In captivity they live 5 to 10 years (Kuiter 2000).

There are probably two species in southern Australasia.  The Eastern (Paxton 1975) and Western Upside-down pipefish (Heraldia sp. Kuiter 2000, undescribed) are usually found swimming upside –down on the ceilings of caves and ledges.  They will swim upside-down in mid water, but will swim upright when on the substrate in aquariums.  Both species of Heraldia are most frequently observed at night. Adults are normally found in pairs.

Eastern Upside-down Pipefish: Heraldia nocturna, Paxton 1975.  Now considered to range from Seal Rocks north of Sydney, New South Wales, Australia, south to Jervis Bay, NSW.  Their habitat includes coves and drowned river valleys on rocky reefs to a depth of 20 meters.  This species adapts well to captivity and reproduces readily. Length to 8 cm.

Western Upside-down Pipefish: Heraldia sp. 1. (prev. nocturna: Kuiter 2000).  This species ranges from the eastern and southern edge of Australia at Port Phillip Bay, Victoria, Australia, then extending westward in low energy coastal bays to Geograph Bay south-western Western Australia.  During the day the Western Upside-down Pipefish can sometimes be observed in crevices through the use of a torch.  This species adapts well to captivity and reproduces readily. Young born in captivity are pelagic but have not survived.  Pelagic fish larvae normally require the provision of large numbers of enriched crustacean larvae of a specific size. Length 10 cm.