Branchiomma.— Claparède, 1869: 162 –163 (not Kölliker, 1858).
Megalomma Johansson, 1925: 130.— Perkins, 1984: 351 –352.— Fitzhugh, 1989: 76.— Fitzhugh, 2003: 107 –108.— Tovar-Hernández and Salazar-Vallejo, 2008: 1953 –1954.
Megalomma bioculatum ( Ehlers, 1887)
Branchiomma bioculatum Ehlers, 1887: 260 –263, Pl. 53, Figs 1–9.— Hartman, 1938: 18. Megalomma bioculatum.— Johansson, 1927: 132.— Hartman, 1965 b: 234.— Perkins, 1984: 352 –354, Fig. 38.
Type locality: Straits off Florida, 24 º 23 ’ 5 ’’ N, 83 º 31 ’ 6 ’’ W, 152.8 m. Type material: MCZ 669 (PT), MCZ 824 (PT).
Records: Not new records.
Megalomma fauchaldi Giangrande, Licciano and Gambi, 2007
Megalomma fauchaldi Giangrande, Licciano and Gambi, 2007: 46 –47, Fig. 2.
Type locality: Belize, Carrie Bow Cay, lagoon side, 16 º 48 ’ 6.92’’ N, 88 º 4 ’ 57.69’’ W, in Thalassia meadows, 3 m.
Type material: MNCN 16.01/ 11018 (HT), USNM 1102753 (PT). Records: Only known for the type locality.
Megalomma heterops Perkins, 1984
Megalomma heterops Perkins, 1984: 359 –363, Figs 42–43.— San Martín et al. 1994: 556.— Tovar- Hernández and Salazar-Vallejo, 2006: 40 –42, Fig. 9.
Type locality: Florida East coast, Hutchingson Island, 27 º 20.7’ N, 80 º 12.8’ W, coarse calcareous sand, 11 m.
Type material: USNM 54721 (HT), FSBC I 27696, 27698 (PT). Records: Cuba ( San Martín et al. 1994), Mexican Caribbean, Florida, British Virgin Islands, Puerto Rico ( Tovar-Hernández & Salazar-Vallejo 2006).
Megalomma lobiferum ( Ehlers, 1887)
Branchiomma lobiferum Ehlers, 1887: 254 –259, Pl. 53, Figs 10–15.-- Hoagland, 1919: 577.— Treadwell, 1924 a: 18; 1939: 291, 292, Fig. 105.— Fauvel, 1953: 17.
Megalomma lobiferum.— Johansson, 1927: 132.-- Perkins, 1984: 354 –357, Fig. 39–40.— Bastida-Zavala, 1993: 25.— Tovar-Hernández and Salazar-Vallejo, 2006: 42 –43, Fig. 10. Type locality: Florida, Key West, 1.68–3.36 m.
Type material: MCZ (HT).
Records: Mexican Caribbean ( Bastida-Zavala 1993, Tovar-Hernández & Salazar-Vallejo 2006); Panama, British Virgin Islands ( Tovar-Hernández & Salazar-Vallejo 2006).
Megalomma perkinsi Tovar-Hernández and Salazar-Vallejo, 2006 Megalomma perkinsi Tovar-Hernández and Salazar-Vallejo, 2006: 43 –45, Fig. 11. Type locality: Florida, Cape Lookout, intertidal sand mixed with gravel and shell fragments. Type material: USNM 53976 (HT).
Records: Only known for the type locality.