Open Access: CC BY 4.0


Masuko, K.

Year: 2019


Larval hemolymph feeding and hemolymph taps in the ant Proceratium itoi (Hymenoptera: Formicidae)

Journal: Myrmecological News

Volume: 29

Pages: 21-34

Type of contribution: Original Article

Supplementary material: No


Queens of the ant species Proceratium itoi (Forel, 1918) ordinarily obtain their nutrition through a phenomenon known as larval hemolymph feeding (LHF), whereby they feed on the hemolymph of final (4th-) instar larvae of their own offspring. Each larva has four pairs of specialized structures on the dorsal integument on the 2nd through 5th abdominal segments. Each structure consists of a small cuticular area with a shallowly cracked surface, resembling the surface of a corncob. Because of these cracks, the queen can break open the cuticular surface by mandibular pinching and intake the hemolymph from the resulting openings. This structure can be considered the P. itoi larval hemolymph tap and is the second confirmed case of such an organ in ants (the first was in Leptanilla). The queen in a developed colony depends exclusively on larval hemolymph for her nutrition, but in an incipient colony, with a small population, the queen suppresses LHF and feeds only on prey. Meanwhile, the workers feed on prey and seldom perform LHF except when the colony is starving. The wounds on the larval integument close shortly after LHF by hemolymph coagulation, and the larvae are repeatedly subjected to LHF, exhibiting multiple scars characteristic of LHF on their dorsa. Similar scars are also found on the dorsa of many prepupae, indicating that they can survive LHF and mature.

Open access, licensed under CC BY 4.0. © 2019 The Author(s).

Key words: Ant, Proceratium itoi, queen, larva, hemolymph feeding, hemolymph tap, coagulation.

Publisher: The Austrian Society of Entomofaunistics

ISSN: 1997-3500

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