https://www.zukan-bouz.com/syu/クモガイ
クモガイ	562
蜘蛛貝	62
くもがい	320
クモ貝	267
くも貝	138

@@ -3,0 +4,18 @@
+<k_ele>
+<keb>クモ貝</keb>
+</k_ele>
+<k_ele>
+<keb>くも貝</keb>
+</k_ele>
+<k_ele>
+<keb>蜘蛛貝</keb>
+</k_ele>
+<r_ele>
+<reb>くもがい</reb>
+<re_restr>くも貝</re_restr>
+<re_restr>蜘蛛貝</re_restr>
+</r_ele>
+<r_ele>
+<reb>クモがい</reb>
+<re_restr>クモ貝</re_restr>
+</r_ele>
@@ -5,0 +24 @@
+<re_nokanji/>
@@ -9 +28,2 @@
-<gloss>Spider conch</gloss>
+<misc>&uk;</misc>
+<gloss>spider conch (Lambis lambis)</gloss>

Spider conch for クモガイ was published in タアロア号　南太平洋をゆく（上）and defined as spider conch in katakana by the author on page 268.

A google image search further defines クモガイ as a type of conch and not as a type of crab.