Species;Shell/size/sex;Pseudopallium;Proboscis;"Host/attach site";"Geographical distribution & depth"
"M. holothuricola Rosén, 1910";"Globose to conical, thin, transparent, fine striae, 4.0–5.5 mm length × 2.0–1.5 mm width";"Bowl-shaped with pleated margin";"Funnel-shaped, white, flexible, rough cuticular surface; not retractable";"Holothuria mexicana respiratory tree";"Bahamas, Campeche Bay, shallow water"
"M. voeltzkowi Shepman & Nierstrasz, 1913";"Ovoid transparent to whitish, slightly smooth 6.5 × 4 mm";"Arises from folds of foot";"Suction disc form, contracted and wrinkled";"Holothuria pardalis? esophageal region";"Zanzibar East Africa, shallow water?"
"M. cantharelloides Humphreys & Lützen, 1972";"Cyrtoconoid and globose, transparent ♀ 5.7 × 4.5 mm";"Bowl-shaped fold of tissue, more extensive in male than female";"Chanterelle-shaped, darkened, contracted";"Stichopus chloronotus intestine";"Picard Island, Aldabra, India, shallow water"
"M. oneirophantae Bouchet & Lützen, 1980";"Globose, vitreous ♀ 9.3 × 7.5 mm, ♂ 3.0 × 1.6 mm";"Base partly covered by foot and its folds";"Long, thin";"Oneirophanta mutabilis within galls in intestine";"Bay of Biscay, 4796 m abyssal depth"
"M. atrae Takano,Warén & Kano, 2017";"Globose, pyriform to biconical, transparent to whitish ♀ 5.2 mm; ♂ 2.0–1.5 mm";Cauldron-shaped;"Long, thickened at the middle into a collar-like";"Holothuria atra, cloacal chamber and respiratory tree";"Japan, New Caledonia, India Australia, tidal waters"
"M. smithi sp. nov.";"Globose to biconical, transparent,finally axial striae ♀6.5 mm L ♂ 4.0 mm";"In folds of foot and cauldron-shaped";"Suction disc form, slightly dark colored retractable";"Holothuria atra cloacal chamber";"Palmyra Atoll, shallow water"