Trigonia acuta Kitchin, 1903 † (original description)
Trigonia brevicostata Kitchin, 1903 † accepted as Magharitrigonia brevicostata (Kitchin, 1903) † (original description)
Trigonia cardiniiformis Kitchin, 1903 † accepted as Kellygonia cardiniiformis (Kitchin, 1903) † (original description)
Trigonia chariensis Kitchin, 1903 † accepted as Trigonia elongata J. De C. Sowerby, 1823 † (original description)
Trigonia crassa Kitchin, 1903 † accepted as Indotrigonia beyschlagi (G. Müller, 1900) † (original description)
Trigonia dhosaensis Kitchin, 1903 † accepted as Kitchingonia dhosaensis (Kitchin, 1903) † (original description)
Trigonia distincta Kitchin, 1903 † accepted as Cornbrashella distincta (Kitchin, 1903) † (original description)
Trigonia dubia Kitchin, 1903 † accepted as Mayesella dubia (Kitchin, 1903) † (original description)
Trigonia exortiva Kitchin, 1903 † accepted as Charigonia exortiva (Kitchin, 1903) † (original description)
Trigonia gracilis Kitchin, 1903 † accepted as Charigonia gracilis (Kitchin, 1903) † (original description)
Trigonia hispida Kitchin, 1903 † accepted as Charigonia hispida (Kitchin, 1903) † (original description)
Trigonia jumarensis Kitchin, 1903 † accepted as Charigonia jumarensis (Kitchin, 1903) † (original description)
Trigonia kutchensis Kitchin, 1903 † accepted as Charigonia kutchensis (Kitchin, 1903) † (original description)
Trigonia mamillata Kitchin, 1903 † accepted as Steinmanella mamillata (Kitchin, 1903) † (original description)
Trigonia nitida Kitchin, 1903 † (original description)
Trigonia parva Kitchin, 1903 † accepted as Trigonia kitchini Strand, 1928 † (original description)
Trigonia propinqua Kitchin, 1903 † (original description)
Trigonia prora Kitchin, 1903 † (original description)
Trigonia pulchra Kitchin, 1903 † (original description)
Trigonia recurva Kitchin, 1903 † accepted as Mayesella recurva (Kitchin, 1903) † (original description)
Trigonia remota Kitchin, 1903 † (original description)
Trigonia retrorsa Kitchin, 1903 † accepted as Opisthotrigonia retrorsa (Kitchin, 1903) † (original description)
Trigonia spissicostata Kitchin, 1903 † accepted as Ghuneriella spissicostata (Kitchin, 1903) † (original description)
Trigonia tenuis Kitchin, 1903 † accepted as Trigonia oomia Strand, 1928 † (original description)
Trigonia trapeziformis Kitchin, 1903 † accepted as Kitchingonia trapeziformis (Kitchin, 1903) † (original description)
Trigonia tumida Kitchin, 1903 † (original description)
Trigonia vscripta Kitchin, 1903 † accepted as Iotrigonia vscripta (Kitchin, 1903) † (original description)