Cantuaria dendyi is a species of trapdoor spider in the family Idiopidae. It can be found in the South Island of New Zealand and is limited to the Christchurch and Banks Peninsula area.
Taxonomy
British amateur arachnologist Henry Roughton Hogg described this species in 1901 as Maoriana dendyi from a specimen collected in Christchurch and sent to him by Professor Arthur Dendy. A year later, Hogg discovered that the genus name Maoriana had already been allocated to a genus of mollusc, so he renamed the species Cantuaria dendyi. The genus name recalls Canterbury Province, the origin of the specimen. Other names for the genus have been Misgolas and Arbanitis. Valerie Todd felt the differences that Hogg had used to place C. dendyi in a new genus were not enough to separate it from the genus Arbanitis, so she reclassified it as Arbanitis dendyi. Additionally, the family Idiopidae was previously considered part of the Ctenizidae.
The first spiders of this genus to be found, Cantuaria dendyi is the type species of the genus.
Description
Cantuaria dendyi is one of over 40 species of Cantuaria recognised today. The main identifying feature of this genus is the presence of a rastellum. This is a set of strong spines used for digging when forming burrows, and are attached to the front of the chelicerae (fang-like mouth pieces). Another way to determine Cantuaria is the presence of only 4 small spinnerets for spinning silk. They are large creatures and the medium size is approximately 2.3 cm with the largest growing up to 3 cm long. However, this size is measured from eye ridge to the end of the abdomen. Therefore, nothing beyond the eye ridge such as legs and fang bases are accounted for and consequently, these spiders are potentially bigger than measurements state. C. dendyi have an abdomen that is cream in colour, with a number of small black patches, which leave three broken pale chevrons on the rear of the abdomen. Both male and females individuals display this chevron pattern on the abdomen, however is not as clear on males as on females. Legs are dark orange brown, as are the palps (segmented appendages near the mouth) of this species Legs differ between sexes. Thick scopula (dense tufts of hair) covers the tarsus and anterior half of the metatarsus of the first two pairs of legs on females, whereas males have thick scopula on the ventral surfaces of both the tarsus and metatarsus on the first two pairs of legs
Distribution and habitat
Cantuaria are endemic to New Zealand, having been present for 85 million years since New Zealand split from Gondwana. They are predominantly found throughout the South Island of New Zealand although they have been known to reside in the lower part of the North Island up to the Whanganui region.
New Zealand's true trapdoor spiders (Idiopidae) prefer grassland regions and have adapted to the change in landscape from human presence and the increase in agriculture. Highest numbers can be found along fence lines and beside roads in self-made burrows with thin lids and the average depth of these burrows ranges between 15 and 30 centimeters. There are exceptions to this as some species such as C. huttoni, can be found on forest floors, however, these spiders usually have an open burrow as opposed to having a “trapdoor”.
Cantuaria are masters of camouflage and accordingly, they are very hard to find. They incorporate nearby material into the silk so that the trapdoors look like the surrounding environment. Once their burrow is built, they do not wander far and consequently, species are scattered in distribution. Cantuaria dendyi is limited to the Christchurch and Banks Peninsula area in the South Island of New Zealand