Checklist of Arachnids in Grassland Habitats of Gombe State, North East Nigeria

This study develops a checklist of arachnid species in grassland habitats of Gombe State, located in Nigeria's North East geopolitical zone. Arachnids are among the most diverse and ecologically important invertebrate groups in grassland ecosystems, performing roles in prey regulation and as indicator organisms, yet formal surveys are absent for Gombe State grasslands. Sampling was conducted at six grassland sites using pitfall traps, sweep netting, and timed hand searches over three months during the dry and wet seasons. Specimens were identified to family and genus level. A total of 34 arachnid genera from 19 families and four orders were recorded. Araneae (spiders) dominated with 24 genera from 14 families. Acari (mites) contributed 6 genera. Scorpiones and Opiliones were each represented by two genera. Lycosidae, Thomisidae, and Salticidae were the richest spider families. Web-building guilds were most abundant during the wet season when arthropod prey was plentiful. Hunting spiders dominated in the dry season. The burrowing scorpion Pandinus imperator was recorded at three sites, representing a significant commercial harvesting species. The study provides the first arachnid species inventory for Gombe State grasslands and recommends standardised annual monitoring to detect population changes in response to land management and climate variability. Keywords: arachnids, spiders, grassland, Gombe State, checklist.