Land snails, Bardee Grubs and the Packalacca -- by Rod Hobson

These few notes are presented as a result of member’s enquiries after our August monthly meeting and the subsequent field trip to Emu Creek. At our monthly meeting two specimens were presented for identification and the member’s comments. The first was displayed by Trish Gardner and was the dead, bleached shell of a native land snail Sphaerospira fraseri (Fraser’s Banded Snail). The mollusc was given to Trish by Steve Plant. Steve had found the shell in an area of revegetated dry vine scrub on his property at Pechey along with another native land snail Pedinogyra hayii (Hay’s Flat-coiled Snail). Both snails are sympatric across a lot of their range in south-east Queensland although Fraser’s Banded Snail extends south into the Clarence River area of north-eastern New South Wales. Both species are found in dry rainforest thickets although Fraser’s Banded Snail also extends into surrounding sclerophyll woodland. Both snails can be found under logs and rocks in damp situations. A very similar snail to fraseri is also found in similar situations in south-east Queensland. It is the Pale Banded Snail Figuladra mattea. Living snails can be easily distinguished as mattea has a red mantle whereas in fraseri this is black. Dead shells are somewhat more problematical to separate. A dead specimen shell of Hay’s Flat-coiled Snail was displayed at our July meeting from dry vine scrub at the base of Camels Hump east of Picnic Point. All these snails are a favourite food of the beautiful Noisy Pitta, Pitta versicolor.

Pupa case of Rain moth Trictena atripalpis (photo M. Rooke)

The second specimen from the night was brought in by Michael Rooke. It was found recently by Michael and Diane Pagel on a walk below Shannon Park at Highfields. It was an old pupa case of the Rain Moth Trictena atripalpis. This moth is also known as the Giant Rain Moth and the larva as a Bardee Grub. The Rain Moth is a widespread species belonging to the family Hepialidae and is found throughout southern Australia including Tasmania. It is a large moth with the wingspan of males reaching 12 cm and those of the female growing to 16 centimetres. The larva of this moth can spend several years underground feeding on the roots of adjacent trees. It emerges from the ground after rain hence its common name. Bardee Grub is somewhat of a misnomer for these larvae as Bardee is more correctly applied to the larva of the beetle Bardistus cibiarius. The discarded pupae cases can be found partly protruding from the ground after rain, as was the case around Toowoomba earlier this year. In March these cases were observed after rain in Garnet Lehmann Park, the Bridle Trail in Redwood Park, in the Lions Park at Picnic Point, on the Pardalote Walk below Picnic Point and from a private residence at Wyreema. The larvae are popular as baits with freshwater anglers.

On our last outing to John and Liz O’Brien’s Emu Creek property a conversation arose about a large, heavily buttressed tree growing close to their residence. It was an old specimen of the exotic Packalacca or Ombu Phytolacca dioica. It is a native of the Pampa of South America where it features heavily in gaucho culture. It can grow into a large tree with a canopy from 12-15 metres and a height of 12-18 metres. It is a valued shade tree and was a popular planting around dairies and livestock pens in south-east Queensland historically, but many have since disappeared, as these areas have been subsumed by urban spread and the dairying industry has declined. They’re getting to be a rarity these days. The large leaves are said to be palatable to cattle, but the roots are reported to be poisonous, however there is some doubt even about the palatability of the leaves as fodder. The Packalacca is in the same genus as the common local weed, the introduced Ink Weed or Dyeberry Phytolacca octandra and the Poke Weed Phytolacca americana from the United States. Pokeweed has been recorded from the Gold Coast hinterland area.  Although the Packalacca is an exotic it doesn’t appear to be invasive and its gaunt, sentinel form over old dairies on the Darling Downs and the Lockyer was a pleasant feature to behold. Its passing is with regret, at least by this writer.