SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f2044663fc1b7d9a35eb225a014d77e6c98ff24ca5c8f4a45e6759b97dc073b' 
  AND token = 'EouMrXwIdJvMRQpF+H9y2F9OTPKrtRjpXZWBgotyZ6M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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