diff --git a/src/syntax_highlighting/main.py b/src/syntax_highlighting/main.py
index c4369ac..b2a86a6 100644
--- a/src/syntax_highlighting/main.py
+++ b/src/syntax_highlighting/main.py
@@ -53,7 +53,11 @@
 #                        to show the user AND
 #  The "language aliases": short, cryptic names for internal
 #                          use by HtmlFormatter
-LANGUAGES_MAP = {lex[0]: lex[1][0] for lex in get_all_lexers()}
+LANGUAGES_MAP = {
+    lex[0]: lex[1][0]
+    for lex in get_all_lexers()
+    if len(lex) > 1 and len(lex[1])
+}
 
 
 ERR_LEXER = ("<b>Error</b>: Selected language not found.<br>"