Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9ce4e0fe5e40c28d9e3ff100da923497d74dff9bb89b47d4682fa291a9bbe3f' 
  AND token = 'JT/BOIljmv8NWjE3XxuDfbqHV6bfdxB9AZx1XdwPWmA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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