Researchers have identified two previously unknown species of herbivorous ladybird beetles in the mountainous regions of southwestern China, adding to the growing list of insect diversity in the area. The new species, named Afissa parabicrescens and Afissa longa, belong to the genus Afissa, a group that has undergone significant taxonomic revision in recent years. These discoveries highlight the ongoing complexity of classifying beetles within the tribe Epilachnini, which includes over 1,000 species worldwide and is known for its intricate nomenclatural history. The findings were published in the journal ZooKeys, providing detailed illustrations and morphological descriptions that help distinguish these new species from their close relatives.
The genus Afissa was originally established by Dieke in 1947, with the type species Coccinella flavicollis. For decades, the classification of this genus remained controversial, leading to its synonymization with the more well-known genus Epilachna by Li and Cook in 1961. However, phylogenetic evidence presented by Szawaryn and colleagues in 2015 supported the resurrection of Afissa as a distinct genus. This reclassification suggested that many Asian species previously assigned to Epilachna actually belong to Afissa, prompting a major reevaluation of the tribe’s taxonomy. The current study contributes to this ongoing effort by examining specimens collected from various locations in Yunnan Province, China.
Afissa parabicrescens is characterized by its reddish elytra, which are marked with black maculae arranged in a specific 2-2-1 pattern. The species can be distinguished from the similar Afissa bicrescens by its elytral punctation and the structure of its male genitalia. In particular, the penis guide of A. parabicrescens is stout in lateral view and slightly longer than the parameres, whereas in A. bicrescens, the penis guide is comparatively slender. The holotype was collected in Tengchong City, Yunnan, at an elevation of 2,155 meters, while paratypes were found in several other locations within the province, including Ximeng, Xishuangbanna, and Puer City. The distribution map provided in the study indicates that this species is currently known only from Yunnan.
The second new species, Afissa longa, is similar in elytral pattern to Afissa gedeensis but can be differentiated by its male genitalia. The penis capsule of A. longa features a distinctly elongate and enlarged outer arm, a trait that sets it apart from A. gedeensis, where the outer arm is shorter. Additionally, the penis guide in A. longa is robust and crescent-shaped in lateral view, with an acute apex that is comparatively short in inner view. The holotype was collected in the Baihualing National Nature Reserve in Baoshan City, Yunnan, at 1,400 meters elevation. Paratypes were also collected from Pingbian, Ruili, Jinhong, and Zhenkang cities, suggesting a broader distribution within Yunnan compared to A. parabicrescens.
In addition to describing the two new species, the study provides a redescription of Afissa bicrescens, a species originally described by Dieke in 1947. The redescription includes detailed measurements and illustrations that clarify its morphological features, such as its black elytra with variable reddish maculae and its simple, slightly curved penis. The study also examines specimens of Afissa cf. gedeensis, noting inconsistencies in previous descriptions regarding the presence of pronotal maculae. These observations raise questions about the taxonomic status of A. gedeensis in China, given that the species was originally described from Java. The authors suggest that a future revision of this species complex is necessary to resolve these uncertainties.
The taxonomic challenges within the tribe Epilachnini are further compounded by the high degree of intraspecific variation in elytral patterns and the frequent description of species based solely on female specimens. This variability makes it difficult to distinguish between closely related species, leading to potential misidentifications. The authors emphasize the need for lectotype designations and the re-examination of type material to clarify these issues. Moreover, the incorporation of molecular data, such as DNA barcoding, is recommended to aid in species delimitation and to associate males and females more accurately. These methods could provide additional evidence to support morphological findings and help resolve long-standing taxonomic debates.
Morphological analysis of the four species discussed in the study reveals distinct groupings based on the structure of their mandibles and tarsal claws. Afissa parabicrescens and A. bicrescens share elongate mandibular apical teeth and tarsal claws with a shorter inner denticle, while A. longa and A. cf. gedeensis possess lamellar mandibular teeth and more robust inner denticles. The authors hypothesize that these differences may be linked to variations in host plant leaf properties, which could influence feeding efficiency and adhesion to substrates. However, the feeding habits and host plant associations of many Epilachnini species remain poorly documented, limiting the ability to test these ecological hypotheses. Further research integrating ecological and morphological data is needed to understand the evolutionary drivers behind these morphological differences.
The discovery of these two new species underscores the importance of continued taxonomic research in biodiversity hotspots like southwestern China. The region’s diverse ecosystems support a wide range of insect species, many of which remain undescribed or poorly understood. By providing detailed descriptions and illustrations, the study contributes to the broader effort to document and classify the world’s insect fauna. As taxonomic methods evolve, incorporating molecular tools and ecological data will be crucial for resolving the complex relationships within groups like Epilachnini. These efforts not only enhance our understanding of biodiversity but also provide a foundation for conservation strategies aimed at protecting these often-overlooked organisms.
Subject of Research: On two new species of the genus Afissa Dieke, 1947 (Coccinellidae, Epilachnini) from southwestern China
Article Title: On two new species of the genus Afissa Dieke, 1947 ( Coccinellidae , Epilachnini ) from southwestern China
Article References: Zhang, X., Zhu, Z., & Wang, X. (2026). On two new species of the genus Afissa Dieke, 1947 (Coccinellidae, Epilachnini) from southwestern China. ZooKeys, 1291, 39-54. https://doi.org/10.3897/zookeys.1291.193001
Image Credits: AI Generated
DOI: 10.3897/zookeys.1291.193001
Keywords: species, genus, Afissa, Dieke, Coccinellidae, Epilachnini, southwestern, China, scientific research
News Source: Drew Townsend. (October 18, 2026). Two New Ladybird Beetles Discovered in China. Scienmag.
