Olfactory information saves venom during prey-capture of the hunting spider Cupiennius salei (Araneae: Ctenidae)

Much is known about the mechanosensory behaviour of the spider Cupiennius Keyserling, but much less about its visual capabilities. In this study the quality of the optical image, the retinal resolution and the fields of view were assessed for each of the four pairs of eyes. The image is of good quality in all eyes. The principal (antero-median) eyes lack a tapetum and have an inter-receptor angle of 2.9°. The three secondary eyes (antero-lateral, postero-median and posterolateral) all have ‘gridiron’ tapeta with receptors arranged in rows. The angular separations (along rows × between rows) are 3.6° × 9.3°, 0.9° × 2.3° and 1.0° × 3.0°, respectively. Although the disposition of eyes on the head is similar to that of pisaurid spiders, all other features of the eyes, including the sizes and shapes of the fields of view, resemble those of lycosid spiders. The peripheral visual system of Cupiennius can thus, in principle, support a similar range of visual behaviour to that of lycosids, which includes prey capture, predator avoidance and courtship.

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Airflow elicits a spider's jump towards airborne prey. I. Airflow around a flying blowfly

Journal of The Royal Society Interface ◽

10.1098/rsif.2012.0186 ◽

2012 ◽

Vol 9 (75) ◽

pp. 2591-2602 ◽

Cited By ~ 9

Author(s):

Christian Klopsch ◽

Hendrik C. Kuhlmann ◽

Friedrich G. Barth

Keyword(s):

Phase I ◽

Prey Capture ◽

Time Dependent ◽

Time Of Arrival ◽

Flow Sensors ◽

Cupiennius Salei ◽

Flying Insects ◽

Dependent Flow ◽

Air Flow Velocity ◽

Hunting Spider

The hunting spider Cupiennius salei uses airflow generated by flying insects for the guidance of its prey-capture jump. We investigated the velocity field of the airflow generated by a freely flying blowfly close to the flow sensors on the spider's legs. It shows three characteristic phases (I–III). (I) When approaching, the blowfly induces an airflow signal near the spider with only little fluctuation (0.013 ± 0.006 m s −1 ) and a strength that increases nearly exponentially with time (maximum: 0.164 ± 0.051 m s −1 s.d.). The spider detects this flow while the fly is still 38.4 ± 5.6 mm away. The fluctuation of the airflow above the sensors increases linearly up to 0.037 m s −1 with the fly's altitude. Differences in the time of arrival and intensity of the fly signal at different legs probably inform the spider about the direction to the prey. (II) Phase II abruptly follows phase I with a much higher degree of fluctuation (fluctuation amplitudes: 0.114 ± 0.050 m s −1 ). It starts when the fly is directly above the sensor and corresponds to the time-dependent flow in the wake below and behind the fly. Its onset indicates to the spider that its prey is now within reach and triggers its jump. The spider derives information on the fly's position from the airflow characteristics, enabling it to properly time its jump. The horizontal velocity of the approaching fly is reflected by the time of arrival differences (ranging from 0.038 to 0.108 s) of the flow at different legs and the exponential velocity growth rate (16–79 s −1 ) during phase I. (III) The air flow velocity decays again after the fly has passed the spider.

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Venom of the hunting spider Cupiennius salei (

Toxicon ◽

10.1016/s0041-0101(97)90325-1 ◽

1997 ◽

Vol 35 (6) ◽

pp. 813 ◽

Cited By ~ 3

Author(s):

L. Kuhn-Nentwig ◽

W. Nentwig

Keyword(s):

Cupiennius Salei ◽

Spider Cupiennius Salei ◽

Hunting Spider

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A homolog of the hydrolase Notum is expressed during segmentation and appendage formation in the Central American hunting spider Cupiennius salei

The Science of Nature ◽

10.1007/s00114-005-0617-1 ◽

2005 ◽

Vol 92 (5) ◽

pp. 246-249 ◽

Cited By ~ 7

Author(s):

Nikola-Michael Prpic ◽

Wim G. M. Damen

Keyword(s):

Central American ◽

Cupiennius Salei ◽

Appendage Formation ◽

Spider Cupiennius Salei ◽

Hunting Spider

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A Visually Induced Switch in Mode of Locomotion of a Spider

Zeitschrift für Naturforschung C ◽

10.1515/znc-1997-1-221 ◽

1997 ◽

Vol 52 (1-2) ◽

pp. 124-128 ◽

Cited By ~ 9

Author(s):

Axel Schmid

Keyword(s):

Behavioral Change ◽

Prey Capture ◽

Complete Darkness ◽

Cupiennius Salei ◽

Locomotion Compensator ◽

Visual Inputs ◽

Sensitivity Range ◽

Locomotion Pattern ◽

Substrate Vibrations ◽

Spider Cupiennius Salei

Abstract The spider Cupiennius salei Keys. (Araneae, Ctenidae) is a nocturnal hunter living on monocotyledones. It does not build webs for prey capture. During the day it remains in its retreat and during dusk it begins to hunt for prey or to search for mates. C. salei is well equipped with mechanosensory systems to detect air- or substrate- borne vibrations elicited by prey or predators. If none of them produce either air movements or substrate vibrations, and the light intensity is below the threshold (0.1 lx), the animal is virtually " blind" . There fore a hypothetical, additional sensory input should exist, which is used only in complete darkness. The animal was tested on a locomotion compensator were it performs constant walks towards a visual target. Three different light intensities were used (bright 200 lx, dim 0.1 lx, and dark at 950 nm, which is outside the spectral sensitivity range of the animal). At bright and dim illumination the animal walked in the alternating tetrapod gait towards the target. In complete " darkness" the walk was no longer directed and the animal changed its gait and continued walking on only six legs using the first pair as guide-sticks. If the first pair is missing, the second cannot replace this function. This shows a twofold use of the first pair o f legs as ordinary walking legs and as guide-sticks or " antennae" . Therefore one can assume that visual input causes a behavioral change, which can not be explained by a fixed locomotion pattern but by adaptive changes caused by visual inputs.

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Effects of size, motility and paralysation time of prey on the quantity of venom injected by the hunting spider Cupiennius salei

Journal of Experimental Biology ◽

10.1242/jeb.202.15.2083 ◽

1999 ◽

Vol 202 (15) ◽

pp. 2083-2089 ◽

Cited By ~ 1

Author(s):

H. Malli ◽

L. Kuhn-Nentwig ◽

H. Imboden ◽

W. Nentwig

Keyword(s):

Prey Species ◽

Prey Size ◽

Experimental Studies ◽

Energetic Cost ◽

Cupiennius Salei ◽

Predator Prey ◽

Minor Significance ◽

Spider Cupiennius Salei ◽

Hunting Spider ◽

Behavioural Adaptations

Previous experimental studies have shown that neotropical wandering spiders (Cupiennius salei) inject more venom when attacking larger crickets. It has been postulated that this is a consequence of predator-prey interactions during envenomation, which increase in intensity with the size of a given prey species. The present study was designed to test this hypothesis using anaesthetized crickets of different sizes that were moved artificially. Cupiennius salei was found (1) to inject more venom the greater the intensity of the struggling movement of the crickets (prey size kept constant); (2) to inject more venom the longer the duration of the struggling movement of the crickets (prey size and intensity of movement kept constant); and (3) to inject equal amounts into crickets of different size (duration and intensity of movement kept constant). These results indicate that C. salei alters the amount of venom it releases according to the size and motility of its prey. Venom expenditure depends mainly on the extent of the interactions with the prey during the envenomation process, whereas prey size is of minor significance. The regulation of venom injection in concert with behavioural adaptations in response to various types of prey minimizes the energetic cost of venom production, thus increasing the profitability of a given prey item.

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