Waterhunting spider
| Waterhunting spider | ||||||||||||
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Waterhunting spider ( Ancylometes bogotensis ) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Ancylometes bogotensis | ||||||||||||
| ( Keyserling , 1877) |
The fishing spider or fishing spider ( Ancylometes bogotensis ) is a web spider from the family crest spiders (Ctenidae). It occurs in Central and South America and should not be confused with the hunting spider Dolomedes aquaticus , which also lives in and around the water in New Zealand .
features
Females of the waterhunting spider reach a body length of 31 millimeters, the males remain smaller with 25 millimeters. The structure is largely similar to that of other comb spiders. What is remarkable is the spider's thick hair, which gives its body a hydrophobic property and thus enables it to glide on the water surface as well as to dive. The tarsers of the males are slightly longer at 5 mm than the 4 mm long tarsers of the females. These both end in three toothed claws, the origin of which is a cuticular plate. The tarsi also have fine hairs. The dorsal side of the legs also has fine sensillae that are at a flat angle to the distal end of the tarsus and are slightly curved. Shorter sensillae are pinnate. The hair on the legs is extended by some protruding trichobothria , which are evenly arranged.
Both sexes have a brown basic color. The carapace of the males is dark brown in color and is flanked by a white-brown border about one millimeter wide. The dorsal sides of the metatarsi of both pairs of forelegs are brightly colored. The abdomen ( opisthosoma ) of the males contains two parallel longitudinal rows each with four light brown spots. The tops of the femurs and the opisthosoma of the female are speckled with yellow and dark brown. The edge of the female's cephalothorax has several dark brown spots near the legs.
Occurrence
The waterhunting spider is common in Central and South America. There she stays near bodies of water such as ponds, lakes and rivers.
Way of life
The waterhunting spider can move about on the water and also submerge , similar to the edged hunting spider , to which it is not closely related, however. When gliding on the surface, the spider, with the exception of the tarsi, lies completely on top and arches the body slightly downwards. A movement on the surface executes the spider rowing. The second and third pair of legs are used for this, the third moving faster than the second. The other two pairs of legs remain in a resting position and are only used to change direction. While the females try to escape by rowing faster when disturbed, the males are also able to jump on the surface of the water. If necessary (such as a stronger disturbance), the waterhunting spider can also submerge about 10 cm below the surface of the water and stay there for up to almost three hours. The species can just as easily move around on land and is also very nimble and agile there, like the other comb spiders . Moving around in the country is similar to that of other representatives of the family.
Hunting & Nutrition
Like the other comb spiders, the waterhunting spider is a free-roaming hunter who does not create webs. In contrast to its related representatives, the waterhunting spider can also hunt on the water surface, depending on its habitat. On the surface of the water, the spider assumes a characteristic lurking position by holding onto land with the two rear pairs of legs near the bank and letting the front pairs of legs and the tarsi linger on the surface of the water. This is used to locate prey on or below water. If any prey is close enough to the waterhunting spider, it rushes at the prey, holds it with its legs and injects its venom with one bite. The paralyzed prey is then pulled ashore and consumed there. On land, the prey is located with the help of the sensilla and the sense of sight. Here, too, the spider lurks in a suitable place and pounces at lightning speed on a suitable prey.
In addition to other arthropods , the waterhunting spider also preyed on small vertebrates such as frogs and other amphibians as well as small reptiles . Tadpoles and small fish , such as the three-colored Jamaican parrot , are also preyed on and under the water .
Reproduction
The reproductive behavior of the waterhunting spider has not yet been fully researched. As soon as a male has reached sexual maturity, it builds a sperm network and then fills its bulbs with the sperm drops released in the network. If a male perceives a female, the male positions himself in front of the female counterpart. Upon observation, the male then began to swing the opisthosoma up and down. In the subsequent copulation, the male first climbs from the front onto the female, who has drawn his legs to the body. The female, who remains motionless, can then be tied to the metatarsi by the male using his filaments. The male starts with the female's front legs. The male circles the female counterclockwise while spinning. In the same observation, the male then climbed onto the back of the female with her thorax facing towards the partner's abdomen. Then the male first introduced his right embolus into the right epigyne and then the left embolus into the left epigyne. The female turned with the corresponding side to the male. The pairing appears to be quite peaceful. So the male left his partner without haste during the observations. The female stirred again some time after the mating was complete.
Individual evidence
- ↑ a b c d e Frank Brzostowicz & Hartmut Greven: Observations on the fishing spider Ancylometes bogotensis Keyserling, 1877 (Araneae) . Acta Biologica Benrodis, 14, pp. 39–54, 2007 ( PDF , German)
