Soil Preference and Burrow Characteristics of Two Theraphosidae Species in Penang Island, Malaysia

  Soil Preference and Burrow Characteristics of Two Theraphosidae Species in Penang Island, Malaysia Abstract Tarantulas play a crucial role in maintaining ecological balance by regulating insect populations. However, little is known about the soil preferences and burrow structures of tarantulas in Malaysia. This study aims to determine the soil preference as well as the burrow structure of  Coremiocnemis cunciularia  and  Chilobrachys andersoni  from Penang Island. The soil characteristics of the soil samples collected around the burrows of  Coremiocnemis cunciularia  (n = 30) and  Chilobrachys andersoni  (n = 30) were determined using soil texture analysis. The measurements and burrow structures from adults and juveniles of  Coremiocnemis cunciularia  and  Chilobrachys andersoni  were determined. It was revealed that the moisture content and clay percentage in the soil samples around burrows of  Chilobrachys anderso...

Aversive conditioning and memory in the harvester Mischonyx squalidus (Arachnida: Opiliones)

 


Aversive conditioning and memory in the harvester Mischonyx squalidus (Arachnida: Opiliones)

Abstract

Aversive conditioning is a form of associative learning. Here, we investigated learning and memory capacity of the harvester Mischonyx squalidus (Roewer, 1913), to examine the formation of short (STM) and long-term memories (LTM). First, we trained harvesters to associate an aversive stimulus (shock) with a neutral stimulus (tea odor). Each subject went through three consecutive trials, in which pairings between the stimuli lasted for 3s, with intervals of 1 (STM) and 30 (LTM) min. Subsequently, to test memory, we introduced the subjects in a choice arena where they could choose between staying in either of two areas: impregnated with tea chemicals or blank. We did this immediately after the conditioning phase or 24h after it. Both protocols were successful for STM within the same-day test, but not for LTM on the following day. In summary, we provide a new method to train aversive conditioning in harvesters and evidence for short-term memory.

Guilherme Ferreira Pagoti, Marina Costa Rodrigues, Gabriel Pimenta Murayama, Rodrigo Hirata Willemart "Aversive conditioning and memory in the harvester Mischonyx squalidus (Arachnida: Opiliones)," The Journal of Arachnology, 53(1), 26-29, (20 June 2025)