Pachyrhinus

Schönherr, 1823

Pine Needle Weevils

Pachyrhinus is a of in the containing more than 30 described . Commonly known as pine needle weevils, members of this genus are herbivorous with elongated snouts typical of weevils. The genus includes significant agricultural pests, notably Pachyrhinus yasumatsui (jujube weevil), which causes severe to Chinese jujube in northern China. A high-quality -level has been sequenced for Pachyrhinus lethierryi from England as part of the Darwin Tree of Life project.

Pachyrhinus californicus by (c) Kalvin Chan, some rights reserved (CC BY), uploaded by Kalvin Chan. Used under a CC-BY license.

Pachyrhinus californicus by (c) Trevor Van Loon, some rights reserved (CC BY), uploaded by Trevor Van Loon. Used under a CC-BY license.

Pronunciation

How to pronounce Pachyrhinus: /ˌpækɪˈraɪnəs/

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Distribution

The has been documented in England, United (Battersea Park, Wetherby Gardens/Kensington, London) and northern China (Jiaxian County, Shaanxi province). Pachyrhinus yasumatsui is widespread in northern China. Pachyrhinus lethierryi has been collected from urban parkland in England. The broader geographic range of most remains poorly documented.

Human Relevance

Pachyrhinus yasumatsui is a major pest of Chinese jujube (Ziziphus jujuba), causing severe economic losses in the jujube industry through feeding damage to fresh and shoots. This has been the of research on chemosensory mechanisms to develop environmentally friendly pest management strategies, including tools based on - volatiles.

More Details

Chemosensory Research

Pachyrhinus yasumatsui has been extensively studied for its olfactory system. Research has identified 113 chemosensory genes including 41 odorant receptors, 28 odorant-binding , 16 ionotropic receptors, 15 chemosensory proteins, 9 receptors, and 4 proteins. The odorant-binding protein PyasOBP2 binds strongly to - volatiles including ethyl butyrate, 2-methyl-1-phenylpropene, and dipentene.

Genomic Resources

The first high-quality assembly for the was generated for Pachyrhinus lethierryi in October 2025. The assembly comprises 619.57 Mb in 11 chromosomal pseudomolecules (10 + ) with a mitochondrial genome of 21.74 kb. The exhibits X0 sex determination with no detected.