SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8ac747319fab8e6ab6893fd48ff047e92ad5ad4d92552e0b979b050c0e887f7' 
  AND token = 'zCCGQGzU6o9RhWcpzX2jbDm+U6niW7wvUbZegg62vwQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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