SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88918aee2c028ef9b46d7b1d2361a8ae5ef2045b2798e75e2e6afe2edef56136' 
  AND token = 'gxG8KNL6xZDI+t7BmlFn6Y8lu9UzVW/uEyEi3aOhzbk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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