SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4bdc41af5f6b9cc199d27c738eb99a2a362fe6324f92b6429ad0f12299179bf' 
  AND token = 'tsjLb/OtJXgBz3HG5h2eCpCpUgxNp+XmhtNLqEYWb+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}