Researchers at Kyushu University in Japan have identified a new species of ladybug, Parastethorus pinicola, which is remarkably small—barely one millimeter in length. This discovery highlights how much biodiversity remains undocumented, even in well-studied areas. The finding came as part of a broader taxonomic update of the Stethorini group of ladybugs, known for their role in controlling spider mite populations.
The Tiny Pine Dweller
The new species, aptly named P. pinicola (meaning “pine dweller”), was found on Japanese black pine trees at the university’s Hakozaki Satellite campus. Lead researcher Ryōta Seki noted that scientists have historically overlooked these tiny insects due to their size and the difficulty in identifying them without dissection. P. pinicola and similar black ladybugs are so small that previous classifications have often been inaccurate.
Clarifying Ladybug Taxonomy
The study, published in Acta Entomologica Musei Nationalis Pragae, involved analyzing around 1,700 specimens. Researchers also resolved a long-standing confusion by confirming that two previously distinct species, Stethorus japonicus and Stethorus siphonulus, are actually the same. A third new species, Stethorus takakoae, was also identified and named in honor of Seki’s grandmother, Takako Ōtsuki, for her support of his entomological pursuits.
Why This Matters
Standardizing these classifications is critical for international scientific collaboration, ensuring data from across Asia is comparable. The discovery underscores that even urban environments and university campuses can harbor undocumented species. These “minor” insects play a vital role in ecosystems, and their existence reminds us of the unseen biodiversity surrounding us.
As Munetoshi Maruyama, co-author of the study, pointed out, “People rarely notice such small insects. But as our study showed, even in a city or on a university campus, there are unknown species living right beside us.”
The identification of P. pinicola emphasizes the need for continued exploration and meticulous study of even the smallest creatures, as they contribute significantly to the planet’s ecological balance.
