SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78c2180cd29c7c8a575da7ac987d91ca17dbd48ac100ca14d9056fab64610147' 
  AND token = 'ez7+pB1EMJyBKZQoWfsuKAEt0SNBc5nRhETAhKBJRWU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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