SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa60c671faa66f11185de840b5c0c19e02ae77964243871357736cfe4d64e797' 
  AND token = 'f08KHnc53UWUiRvwI3LqtP91u7Txz0IjvIO7chDOQnM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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