SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd18f2910a6f8ae1c439612fb09d7e9d40a8afeb5722a1c68705ae66193262045' 
  AND token = '5EYEY5J9XJmLJj+vuzHgqyusypunLkcxlILBv9U+HQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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