SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '522ab784a477aa40d9cfa48cdc7b2b6d3af474439577885a4f1799ddd2b07c12' 
  AND token = 'hZoIV9D96KmTW2j3PtHkauQODWE7QfNkKc2Rd1+7zbs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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