SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24c28e2506f611f0fed9e3c3c1fb4897a4c61d41e88e2a7fdc43d10b9049bbd7' 
  AND token = 'XoRITYxxelDsZnZPk3ECfnNoIfztzFCfbdANqW6Hcdo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}