SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0688adb4a4da2d581978d52db4185be3a175df43bd8107aa5923e376c352ca07' 
  AND token = 'XwPREeJ/Ws6qhFlfHS9YTUiZrdLXk1QszTyqzKRmWXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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