Sphintharinae > Thwaitesia O. P.-Cambridge, 1881 T. argentiopunctata (Rainbow, 1916), T. nigronodosa (Rainbow, 1912) and perhaps others

Thwaitesia, but what species?

Australian Thwaitesiaare apparently not commonly observed, as there are very few photographs of this genus on the web, in field guides or in spider picture books. Were it more common there would surely be many spectacular photos of these very pretty spiders, sparkling golden and silver, with long, slender transparent legs and a mostly translucent cephalothorax. They are not aggressive and unlikely to be harmful, but should be handled with care as they belongs to the same family as the Redback.

Of the possible Thwaitesia species worldwide, of which only 23 are described (Platnick 10.5), only two are known from Australia, both named by Rainbow. They are T. argentiopunctata named in 1916 initially as Argyrodes argentiopunctata and T. nigronodosa named Argyrodes nigronodosa in 1912. Both are known only from Queensland and were transferred to Thwaitesia by Davies and Gallon in 1986. Many more undescribed species are sure to exist, some of which may be depicted in the photographs below. Many of these photos, however, could well be various stages of the described species as there many be considerable variation within each species, especially in the case of juveniles. Without the specimen to examine with a microscope, the identification cannot be confirmed. Even then, species cannot be reliably differentiated on the basis of Rainbow's drawings, descriptions and type species. Thwaitesia spiders are closely related to Chrysso species.

As it stands in the meantime, it seems that T. nigronodosa has black leg joints while T. argentiopunctata has brown leg joints; also T. nigronodosa has a dark line/mark running lengthways halfway down the cephalothorax while T. argentiopunctata has a dark line/mark running all the way down the cephalothorax; and T. nigronodosa has a black, silver and gold upper abdomen while T. argentiopunctata has a black and gold upper abdomen with a silver blobby stripe, often fringed by red.

T. nigronodosa? Adult female from above
T. nigronodosa? juvenile or another species? from above
T. nigronodosa? juvenile or another species?
T. nigronodosa, black dots, gold, faint red
T. Nigronodosa, Mt Glorious, male adult from above
T. argentiopunctata?
T. argentiopunctata?
T. argentiopunctata? Blobby silver stripe facing from above
T. argentiopunctata? Blobby yellow stripe
T. argentiopunctata? Blobby silver stripe
T. argentiopunctata Female adult 8710 from above
T. argentiopunctata Female adult 8710 from above
T. argentiopunctata Female adult 8710 from side
T. argentiopunctata Female adult 8710 from above
T. argentiopunctata Female adult 8710 from underneath
T. argentiopunctata Male 8710 underneath showing palps
T. argentiopunctata Male 8710 from above
T. argentiopunctata Male palp 8710
T. argentiopunctata Male palps 8710
T. argentiopunctata Female from side 8710a
T. argentiopunctata Female epigyne 8710
Thwaitesia North Queensland 1
Thwaitesia North Queensland 2
Thwaitesia argentiopunctata 19610 in alcohol from above, side
Thwaitesia argentiopunctata 19610 in alcohol from above
Thwaitesia argentiopunctata 19610 in alcohol epigynum
Thwaitesia argentiopunctata 19610 in alcohol epigynum
Thwaitesia argentiopunctata 19610 in alcohol palp

T. nigronodosa? Adult female from above

This specimen is a stunningly patterned spider typical of the genus, about 5mm body length observed in dry rainforest merging with dry eucalypt forest near Enoggera Creek. The dorsal surface of the abdomen has a gold and black/dark brown pattern, the sides of the abdomen feature a cobblestone pattern of silver shapes. The abdomen is highly peaked towards the rear end. Both the silver and gold markings are highly reflective and sparkle in sunlight. This species makes a small tangled web in green vegetation.

Photo: Robert Whyte

T. nigronodosa? juvenile or another species? from above

This spider appeared to be a very juvenile male, body length about 2.5mm, with a very blobby pattern of black and gold on the abdomen. The blobs were on the high peak of the abdomen and the front edge as well as the sides/middle. Four obvious blobs in all. The joints of the legs are particularly black. Collected on the creek near the SOWN shed, Paten Park in early July 2009. Body length about 2.5mm.

Photo: Robert Whyte

T. nigronodosa? juvenile or another species?

This specimen, not the same as above, looks a little older. Very strongly marked with very dark leg joints. Body length about 3mm. Collected mid July 2009 on "The Island" on the northern side of the junction of Fish and Enoggera Creeks, Walton Bridge Reserve, The Gap. One can see the possibility that this spider may develop, when mature, marking similar to the adult above (first photo).

Photo: Robert Whyte

T. nigronodosa, black dots, gold, faint red

This specimen looks somewhat like both the possible species listed here. It was collected in early September on the northern side of the junction of Fish and Enoggera Creeks, Walton Bridge Reserve, The Gap. Many Thwaitesia (more than 50 specimens) have been collected there in an area 100m x 20m along and adjacent to the northern bank of the creek in 2009. This one has the dorsal median longitudinal line extending only halfway and has some small black dots including two close together on the leading edge of the abdomen, and two wider apart on the rear end.

Photo: Robert Whyte

T. Nigronodosa, Mt Glorious, male adult from above

Photo: Dr Greg Anderson

T. argentiopunctata?

Photo: Robert Whyte

T. argentiopunctata?

This specimen, as with all Thwaitesia we have found, was a timid spider in dry rainforest merging to dry sclerophyl. It was found in the remnant rainforest near the junction of Fish and Enoggera Creeks. Its sparkling colours may help with camouflage. The female grows up to about 5mm, the male is reported to reach 3mm.

Photo: Robert Whyte

T. argentiopunctata? Blobby silver stripe facing from above

Body length about 4mm strong silver blobby stripe fringed with red, very little black, tall peaked abdomen, Collected on the creek near SOWN Shed Latitude: 27.451319ºS Longitude: 152.950831ºE Altitude:36 ft

Photo: Robert Whyte

T. argentiopunctata? Blobby yellow stripe

Juvenile female? Body length 3mm. Yellow (not silver) blobby stripe fringed with some red, high peaked abdomen

Photo: Robert Whyte

T. argentiopunctata? Blobby silver stripe

This specimen shows the silvery blobs lengthways on the upper surface of the abdomen. Collected mid June 2009 on "The Island" on the northern side of the junction of Fish and Enoggera Creeks, Walton Bridge Reserve, The Gap. Body length: 4mm. This spider looks similar to the one above, except the yellow blobs are turning silver.