Haustellum is a genus of medium-sized sea snails, marine gastropod mollusks in the family Muricidae, the murex snails or rock snails. Like many other genera within the Muricidae, the genus has been redefined several times. Ponder & Vokes (1988) and Vokes (1990) included American and Indo-Pacific species in Haustellum, which differs from Murex sens...
sucking proboscis or sucking end
• (n.) The sucking proboscis of various insects. See Lepidoptera, and Diptera.
Haus·tel'lum (has*tĕl'lŭm) noun ; plural Haustella (- lȧ). [ New Latin ] (Zoology) The sucking proboscis of various insects. See Lepidoptera , and Diptera . 
Distal portion of proboscis in adult Diptera.
haustellum In certain insects, a proboscis adapted for sucking blood or juices of plants.