diff --git a/src/space.c b/src/space.c
index 4dab9346fa8a0af0d04984d2f3c43437eaa877e5..5e3c1a51711104530c27337abd82349802c5623a 100644
--- a/src/space.c
+++ b/src/space.c
@@ -2703,7 +2703,7 @@ void space_init_gparts(struct space *s, int verbose) {
 
   if (s->nr_gparts > 0)
     threadpool_map(&s->e->threadpool, space_init_gparts_mapper, s->gparts,
-                   s->nr_gparts, sizeof(struct part), 0, NULL);
+                   s->nr_gparts, sizeof(struct gpart), 0, NULL);
   if (verbose)
     message("took %.3f %s.", clocks_from_ticks(getticks() - tic),
             clocks_getunit());