The Taiwan Chrysomelid Research Team was organized by myself and Hsing-Tzung Cheng (鄭興宗) during 2005. Mr Cheng made detailed inventories and photographs of insects and developed a website, “Insect Observation at Sishou Hills” (Cheng 2004). We focused on leaf beetles as the study group and recruited amateurs as a research team. The aim was to inventory all chrysomelid species in Taiwan. In addition to publishing taxonomic works, printing books for educating citizens was also an important goal. The first volume of “The Chrysomelidae of Taiwan” was published in 2007. One hundred easily recognized species were featured (Lee and Cheng 2007). The first paper based on the research team’s collection was published in the same year (Hayashi and Lee 2007). Annual meetings began in 2008 (Fig. 1A), with eight attendees: Su-Fang Yu (余素芳), Chi-Feng Lee (李奇峯), Hsing-Tzung Cheng (鄭興宗), Hou-Jay Chen (陳厚潔), Hsuei-Hon Han (韓學宏), Chih-Kai Yang (楊智凱), Hsueh Lee (李雪), and Mai-Hua Tsou (曹美華). The name “Taiwan Chrysomelid Research Team (TCRT)” was used in Lee and Beenen’s paper (2009) for the first time. In the same year (Lee and Staines 2009), a new species was named for one of TCRT members who first collected the new species. The second book volume was published in 2010 (Lee and Cheng 2010). Two additional members, Jung-Chang Chen (陳榮章) and Min-Der Chen (陳銘德) joined the TCRT in the same year (Fig. 1B). Mr Chen was very active in collecting leaf beetles and made great contributions to the study of Lochmaea Weise (Lee 2019). The third book volume was published in 2016 (Lee et al. 2016). Subsequently, we organized a forum to celebrate the publication of the third volume and the tenth anniversary of TCRT (Fig. 1C, D). The story of TCRT was reported on the TV program (Tzu Chi DaAiVideo大愛電視) during the same year (Discovery 2016) (Fig. 1E) and contributed to a popular-science program (PTSKIDS小公視) the same year (Follow me go! 2016). We set up a stand for introducing TCRT and sold posters during the 39^th Annual Meeting of the Taiwan Entomological Society in 2018 (Fig. 1F, G). The role of “Citizen Science” in academic studies was addressed by me in 2019 on a TV program (Tzu Chi DaAiVideo大愛電視) (Humanities Lecture 2019). TCRT made the first video to introduce interesting leaf beetles of Taiwan to the public (TCRT in Action! 2019). TCRT has attempted to observe the complete life cycles of leaf beetles the room temperature.

Figure 1. 

Historical photographs of the TCRT A first annual meeting of TCRT in 2008 (from left): Hsuei-Hon Han, Su-Fang Yu, Chih-Kai Yang, Chi-Feng Lee, Hsueh Lee, Hsing-Tzung Cheng, Mei-Hua Tsou, Hou-Jay Chen B annual meeting of TCRT in 2010 (from left): Mei-Hua Tsou, Su-Fang Yu, Hou-Jay Chen, Jung-Chang Chen, Chi-Feng Lee, Hsing-Tzung Cheng, Hsueh Lee, Min-Der Chen C Hsing-Tzung Cheng introduced the third volume of the book “The Chrysomelidae of Taiwan” during a forum for celebrating the tenth anniversary of TCRT D Su-Fang Yu autographed the book at the forum E Su-Fang Yu worked as actress on the TV program “Discovery” on the DaAiVideo (大愛電視) F exhibit during the 39^th Annual Meeting of Taiwan Entomological Society in 2018 (from left): Chi-Feng Lee, Wen-Chuang Liao, Mei-Hua Tsou, Su-Fang Yu G Su-Fang Yu and Mei-Hua Tsou stood besides the poser during the meeting in 2018 H annual meeting in 2025 (from left): Yen-Cheng Hsu, Jung-Chang Chen, Yi-Ting Chung, Hseuh Lee, Shiang-Lien Yang, Yi-Chia Chiu, Chi-Feng Lee, Hsing-Tzung Cheng, Min-Der Chen, Chen-Han Ma, Mei-Hua Tsou, Su-Fang Yu.

We cooperated with students and faculty at universities for some species living in alpine habitats. For example, Chrysolina laeviguttata Chûjô, 1958 is the only member of the genus living in such environments (in Alishan 阿里山). The study on its biology was completed in collaboration with students and faculty at the National University of Tainan with access to thermostatically controlled incubators (Luo et al. 2021).

Recently, five new members joined TCRT, including Yen-Cheng Hsu (徐彥承), Yi-Ting Chung (鍾奕霆), Shiang-Lien Yang (楊庠廉), Yi-Chia Chiu (邱奕家), and Chen-Han Ma (馬承漢) (Fig. 1H). To date, 89 taxonomic papers have been published from the inventory of TCRT.

Although this article integrates my previous studies, all Taiwanese species of wingless galerucines were studied using the following procedures. Researchers investigated or collected wingless species at various localities during night hours to determine which species are present. When specimens were located, researchers observed them to determine host plants. When host plants were found, searches were conducted at different localities at night to document patterns of distribution and activity. Observations were made at the same place once or twice each month to investigate patterns of occurrence of adults and larvae. Live females were collected for laboratory rearing to document complete life cycles under controlled conditions.

Beenen and Jolivet (2008) listed several brachelytrous chrysomelids in alpine regions and suggested that brachelytrous species are relatively more numerous in these habitats. However, the best evidence to support the reduction of hindwings resulting from selection of alpine environments is to compare both winged and wingless species in the same genus, which allows testing across different habitats in monophyletic taxa. In Taiwan, alpine environments are above ~2800−2900 m elevation and are characterized by strong winds and low temperatures, which can be defined by subalpine coniferous vegetation (Zelený 2019). Only short grasses and small trees with thick leaves prevail in these areas (Fig. 2A).

Figure 2. 

Lochmaea tsoui Lee, 2019 A Central Cross-Island Highway B feeding marks made by mining first-instar larvae C first-instar larva concealed under coiled leaf D third-instar larva E pupa. (after Lee 2019)

Lochmaea is a good candidate for comparative analysis because it comprises in Taiwan two winged and three wingless species (Lee 2019). Members of the genus are univoltine. Larvae and adults of Lochmaea feed on leaves of various species of Rhododendron (Ericaceae) at different localities. Several young larvae (first instar) were collected from R. pseudochrysanthum Hayata in the same area in Kunyang (昆陽, 3050 m, May 10, 2009) (Fig. 2B, C) and transferred to the laboratory for rearing. Mature larvae (Fig. 2D) burrowed into the soil and built underground chambers for pupation (Fig. 2E) on the 15^th day (May 25). Adults emerged from the soil after 24 days (June 28). Twenty larvae transformed successfully into adults. Among them, 18 were identified as L. lesagei Kimoto, 1996 (winged) and the other two as L. smetanai Kimoto, 1996 (wingless).

Adults are nocturnal and active on host plants at night. However, they don’t crawl down and shelter on the ground during the daytime. Thus, adults can be collected effectively by beating host plants during the day or night, and they can be trapped using Malaise traps. A number of adults of L. lesagei were collected in one Malaise trap set at Yuanfeng (鳶峰, 2756 m) from 2001 to 2006. Records indicated that adults were active from April to November and overwintered from December to March. Lee (2019) studied more than 520 specimens. Adults of Lochmaea lesagei (Fig. 3A) and L. tsoui Lee, 2019 are winged. They occur not only in alpine areas but also in lower elevation mountains above 1000 m (Fig. 3B). However, the three wingless species (L. smetanai, L. cheni Lee, 2019, and L. jungchani Lee, 2019 (Fig. 3C)) were only collected from alpine areas (Fig. 3D). The distributions of these two species groups indicated that reduction of hindwings similar to that of elytra results from adaptation to alpine environments, with winged forms occurring in intermediate elevations.

Figure 3. 

The genus Lochmaea Weise A L. tsoui, a winged species B distribution of winged species of Lochmaea in Taiwan C L. chen, a wingless species D distribution of wingless species of Lochmaea in Taiwan. Solid line: 1000 m, broken line: 2000 m, black areas: 3000 m; different colors represent different species. (after Lee 2019)

Among those orders of insects in which both winged and flightless species occur, both sexes are most frequently flightless in six orders, females in nine orders, and in two orders the male is the predominant flightless sex (Roff 1990). Roff (1990) suggested that loss of flight is favored in females because it permits greater allocation of resources to egg production, but that flight is retained in males because it increases the probability of finding a mate. Females of all Taiwanese species of Paraplotes are physogastric (Fig. 4B) and brachelytrous, while males have normal abdomens (Fig. 4B–D) and elytra (Fig. 6A). This phenomenon is extremely rare among chrysomelids. Moreover, in Paraplotes females appear to be brachyelytrous, whereas they are apterous in Clavicornaltica and Metacycla.

Figure 4. 

The genus Paraplotes Laboissière A typical microhabitat B pair of adults C male of Paraplotes taiwana feeding on the leaves of Pilea rotundinucula at night D male of Paraplotes yuae feeding on the leaves of Dumasia villosa subsp. bicolor at day E eggs F larvae. (Lee 2015)

Species of Paraplotes are multivoltine. Adults are nocturnal and closely associated with their Urticaceae host plants (Pilea spp. (Fig. 4C) and Lecanthus peduncularis (Wall. ex Royle) Wedd.). These plants are widely distributed and grow on the edges of forests and along roadsides (Fig. 4A), walking trails, and rivers. These environments are easily accessible, hence adults can be collected by searching host plants at night. Females deposit eggs on the roots of plants (Fig. 4E). Larvae feed on young leaves and soft shoots (Fig. 4F). Mature larvae leave the host plant and burrow into the soil, where they build chambers underground for pupation. Duration of immature stages is typically less than one month. Collections were made by searching for adults on host plants at night. More than 500 specimens were collected from all over Taiwan (Lee 2015). Adults of Paraplotes were also collected using Malaise traps installed around host plants. A few adults of P. taiwana were collected using Malaise traps in Tulanshan (Taitung County). Adults were collected during all months except January, February, and March, with peak abundance during late June to late August. This species is limited to lowlands no higher than 1500 m (Fig. 5A).

Figure 5. 

Distribution of Paraplotes species of Taiwan, solid line: 1000 m, broken line: 2000 m A widespread species, P. yuae indicated by green spots, P. taiwana indicated by blue spots B localized species, different colors represent different species (details in Lee 2015)

Ten species of Paraplotes are recognized in Taiwan. Five of these are widespread and inhabit lowlands (Fig. 5A), but the other half are restricted to a few localities in mountainous areas (Fig. 5B). Reduction of hind wings in females varies greatly among different populations, although most females in the same populations have similar hind wing lengths. For example, the range of variation of reduction of hindwings is extreme in populations of P. yuae (Fig. 6B–D) in northwest Taiwan (Fig. 5A). Females collected from Wushihkeng (烏石坑) have the least reduced hind wings (38%) (Fig. 6B). In contrast, reduction is more extreme in Wuchihshan (五指山) (18%) (Fig. 6D). Such variations may result from the occasional occurrence of diurnal behavior in the population at Wushihkeng. More than 10 males of P. yuae were observed gathering and feeding on leaves of Dumasia villosa subsp. bicolor (Hayata) Ohashi & Tateishi (Fabaceae) (Fig. 4D) during the day on July 13, 2008. However, an additional 15 adults were collected at night on another occasion (March 21, 2013). Thus, the reduction of hind wings seems to be promoted by the change from diurnal to nocturnal habits. Based on Southwood’s assumption (1962), diurnal habits are environmentally unstable (risky) compared to nocturnal habits.

Figure 6. 

Paraplotes yuae, hindwing A male B female, Wushihkeng (烏石坑) C female, Anmashan (鞍馬山) D female, Wuchihshan (五指山); all hindwing in same scale (Lee 2015)

This genus was considered brachelytrous and monotypic when Chûjô (1962) erected it. Adults are nocturnal and closely associated with their host plants: Clinopodium laxiflorum var. taiwanianum Hsieh & Huang (Fig. 7A) (Lamiaceae), Strobilanthes flexicaulis Hayata (Acanthaceae), and Hemiboea bicornuta (Hayata) Ohwi (Fig. 7B) (Gesneriaceae). These plants are widely distributed and grow on the edges of forests and along roadsides, walking trails, and rivers. These environments are easily accessible; hence, adults could be collected by searching host plants at night. Shairella species appear to be univoltine based on field observations (unpublished data TCRT). Larvae are diurnal and found on the host plant’s leaves during late February. They are easily discovered when feeding on the tops of leaves during the day (Fig. 7C). Larval development takes about one month, based on laboratory rearing. Mature larvae leave the host plant and burrow into the soil, where they build underground chambers for pupation. Pupal stage (Fig. 7D) duration is about 20 days, and adults begin to emerge after early April. Adults are nocturnal and have been observed in the field from May to August. Approximately 240 specimens have been collected throughout Taiwan (Lee and Beenen 2017). The distributions of Shairella species seem to be determined by their host plant. They can be separated into two species groups based on morphology and host plants. Adults of the S. aeneipennis group with noticeably reduced elytra (Fig. 7E) are associated with Clinopodium laxiflorum var. taiwanianum Hsieh & Huang (Lamiaceae) (Fig. 8A). This plant grows in middle elevations (1500– 2500 m) in central Taiwan (Fig. 8B). Four members of this group (Fig. 8A) are monophagous and their distributions coincide with the distribution of the host plant (Fig. 7B). The S. cheni group with less reduced elytra (Fig. 7F) includes three species in southern and southeastern Taiwan (Fig. 8A), which is out of the range of Clinopodium laxiflorum var. taiwanianum (Fig. 8B). The host plant of these species is Strobilanthes flexicaulis Hayata (Acanthaceae) and Hemiboea bicornuta (Hayata) Ohwi (Gesneriaceae) (Fig. 7B), which are abundant at low elevations.

Figure 7. 

The genus Shairella Chûjô A Clinopodium laxiflorum var. taiwanianum (Lee & Beenen, 2017) B Hemiboea bicornuta (Lee, 2022) C Larva of S. guoi feeding on leaves of Strobilanthes flexicaulis D pupa of S. guoi E Adult of S. aeneipennis species group (Lee & Beenen, 2017) associated with C. laxiflorum var. taiwanianum F adult of S. cheni species group (Lee and Beenen 1027) associated with H. bicornuta G adult of S. quadricostata (Lee 2022) associated with H. bicornuta.

Figure 8. 

Distribution of brachelytrous Shairella species and Clinopodium laxiflorum var. taiwanianum A solid line: 1000 m, broken line: 2000 m; different colors represent different species, circles represent species associated with C. laxiflorum var. taiwanianum, squares represent species associated with H. bicornuta B C. laxiflorum var. taiwanianum (after Lee and Beenen 2017).

Shairella quadricostata (Kimoto, 1996) (Fig. 7G) was transferred from Japonitata with normal elytra, and adults feed on leaves of H. bicornuta (Lee 2022). Hindwings are normally developed (Fig. 10A) in northern and central Taiwan and low-elevations of southern Taiwan (Fig. 9), but they are reduced to different degrees between different populations of mid-elevations of southern Taiwan (Figs 9, 10B–E). They are allopatric relative to other members of the genus except at Erhwanping (二萬坪) and Hsitou (溪頭), where S. aeneipennis also occurs (Fig. 9). However, they are separated ecologically since both species utilize different food plants (H. bicornuta for S. quadricostata and C. laxiflorum var. taiwanianum for S. aeneipennis). Adults of S. hsiehae Lee & Huang, 2023 were collected from Peitawushan (北大武山) on the same trail as S. quadricostata. However, they occurred at higher altitudes (above 1600 m), while adults of S. quadricostata were found at localities below 1000 m. Thus, both species are presumably allopatric, occurring at different altitudes.

Figure 9. 

Distribution of Shairella quadricostata and brachelytrous Shairella species, solid line: 1000 m, broken line: 2000 m. Green squares, brachelytrous species; blue circles, adults of S. quadricostata with normal hindwings; red circles adults of S. quadricostata with reduced hindwings.

Figure 10. 

Hindwings of Shairella quadricostata A female, from Wulai (烏來) B female, from Tengchih (藤枝) C female, from Erhwanping (二萬坪) D female, from Hsito (溪頭) E male, from Peitawushan (北大武山). (Lee 2022)

Adults of S. quadricostata (Fig. 7G) possess long antennae and a darker color and are adapted to nocturnal activity. Some populations have reduced hindwings (Fig. 10), presumably as an adaptation to stable microhabitats (mid-altitudes in south Taiwan) based on Southwood’s assumption (1962) (Fig. 9). Mountains represent historically persistent habitats, because populations can move upward or downward to minimize the impact of climatic fluctuations. Mountains are also isolated and represent an energetically costly environment for flight (Wagner and Liebherr 1992). In some Shairella species, elytra are reduced (Fig. 7F) due to allopatric speciation in southern Taiwan (Fig. 8A). Possibly, the shift in host plants resulted in adaptive radiation, leading to reduced elytra (Fig. 7E) in mid-altitudes of central Taiwan (Fig. 8A).

Moss (Bryophyta) cushions constitute a special environment characterized by several important features: food source and habitat for overwintering when many tracheophytes are absent; buffered temperature and moisture; and the small size of spaces among the stems and leaves within cushions (Glime 2006). Based primarily on taxonomic surveys, various habitats have been cited as having inordinately high frequencies of flightless insects (Roff 1990), but this kind of habit is omitted. Only 52 leaf beetle species from 15 genera are documented to live within moss cushions (bryobionts). All moss-inhabiting leaf beetles belong to the tribe Alticini, a group of about 12,000 species worldwide (Konstantinov et al. 2013). Of this group, some species of Benedictus Scherer, Cangshanaltica Konstantinov et al., Ivalia Jacoby, Paraminota Scherer, Paraminotella Döberl and Konstantinov, and Phaelota Jacoby are known to occur inside moss cushions or leaf litter in various regions of Asia. These species are characterized by small, round bodies and the absence of wings (Döberl and Konstantinov 2003; Konstantinov et al. 2013; Damaška and Konstantinov 2016; Damaška and Aston 2019; Damaška et al. 2020, 2022; Ruan et al. 2020, 2022, 2023; Takemoto and Suenaga 2021).

The genus Taiwanoshaira is the first genus of moss-feeding Galerucinae s. str. described that is endemic to Taiwan (Lee and Beenen 2020). Adults are nocturnal, with feeding and mating in moss cushions at night (Fig. 11). Adults were collected in Malaise traps set at specific localities such as Meifeng (梅峰), Yuanfeng (鳶峰), Hsiaofengkou (小風口), and Bilu Divine Tree (碧綠神木) (Fig. 12). During visits to these localities, more than 150 specimens were captured by hand-collecting at night.

Figure 11. 

The genus Taiwanoshaira Lee & Beenen A microhabitat for T. taipingshanensis and T. tsoui Lee & Beenen at Yuanyang Lake (鴛鴦湖) B active adults of T. chujoi inside moss cushions at Pilu (畢祿) C adult of T. taipingshanensis feeding on leaves of Plagiomnium vesicatum at Yuanyang Lake (鴛鴦湖) D adults of T. taipingshanensis mating at Yuanyang Lake (鴛鴦湖) (after Lee and Beenen 2020).

Figure 12. 

Distribution of Taiwanoshaira species, solid line: 1000 m, broken line: 2000 m. Blue dots, T. chujoi; blue squares, historical records for T. chujoi; red dots, T. tsoui; green dots, T. taipingshanensis (after Lee and Beenen 2020).

Mosses are common all over Taiwan due to high humidity and precipitation. They are most dominant in cloud forests, which cover most montane areas above 1000 m altitude. However, species of Taiwanoshaira are restricted to limited areas, based on the TCRT’s collecting experience (Fig. 12). Moreover, they were absent at some localities where they were recorded 40 years ago, such as Tapan (達邦) and Alishan (阿里山) for T. chujoi. They are currently common in only a few places, including Yuanyang Lake (鴛鴦湖), Hsiaofengkou (小風口), and Bilu Divine Tree (碧綠神木). Of these localities, the climatic patterns of the cloud forest at Yuanyang Lake (鴛鴦湖) were studied from 1994 to 2004 (Lai et al. 2006). This site (24°35'N, 121°24'E) is situated in Chi-Lan Mountain at an elevation of 1650 to 2420 m above sea level, where the annual mean air temperature is 12.7 °C and the relative humidity exceeds 90%. The annual precipitation varied between 2109 mm (in 1995) and 4727 mm (in 2001), with an average of 3396 mm, spread over 239 mean rainy days per year. These occurrences indicate that Taiwanoshaira species favour microhabitats with high humidity year-round. Large moss cushions provide moist microclimates without large fluctuations and thus represent a stable and largely predictable habitat.

Although Sikkimia is widespread in continental Asia and Taiwan, only Taiwanese species are wingless and nocturnal (Lee and Bezděk 2016) (Fig. 13). Taiwanese species of Sikkimia appear to be univoltine, based on field observations. Larvae are nocturnal and found on the underside of leaves between February and April. Larval development took 20–22 days under laboratory conditions (Fig. 14A, B). Mature larvae left the host plant and burrowed into the soil, where they built underground chambers for pupation. The pupal stage lasts about 22 days, and adults begin to emerge after April. Adults were nocturnal and lived for more than three months, a lengthy life span for chrysomelids. Presumably, Sikkimia species overwintered as adults, as some females were collected during winter. Adults and larvae were closely associated with the host plant Polygonum chinense L. (Fig. 14A). This plant is widely distributed and grows on the edges of forests, roadsides, walking trails, and rivers. The northern species, Sikkimia tsoui Lee & Bezděk, feeds on Rubus species (Rosaceae). Since these habitats are easily accessible, adults can be collected by searching on host plants at night. Approximately 350 specimens were collected all over Taiwan.

Figure 13. 

Males of Sikkimia species, dorsal view A S. rufa (China) B S. sufangae (Taiwan) C S. tsoui (Taiwan) (Lee and Bezděk 2016).

Figure 14. 

The genus Sikkimia Duvivier A larva of S. sufangae feeding on Polygonum chinense B larva of S. tsoui feeding on Rubus corchorifolius C female of S. tsoui. feeding on leaves of R. swinhoei D female of S. sufangae (Lee and Bezděk 2016).

Adults of Taiwanese species are characterized by a reduction of the hindwings and elytral humeral calli (Fig. 13B, C). The reduction of hind wings may result from the production of physogastric females (Fig. 14D). Nocturnal behavior presumably increases survival since natural enemies are less of a threat. As observed in adverse environments such as islands, deserts and alpine regions, flight is not essential at night, and energy can be delivered to egg production, as suggested by Beenen and Jolivet (2008).

All Sikkimia species are allopatric, restricted to different mountain ranges, and not separated by elevation. Populations of S. tsoui have a wide distribution and occupy northern and central Taiwan (Fig. 15). In addition to its wider distribution, populations of S. tsoui are abundant in some areas (increased fitness). For example, there were many adults at Hsitou (溪頭) and Yuanyang Lake (鴛鴦湖) with more than 50 individuals collected in one night. Both features may reflect the development of some unique characters in S. tsoui. Males of S. tsoui lack enlarged apical antennomeres (Fig. 13C), a character that may be involved in complex courtship behavior and the lack of this secondary sexual character may result in lower speciation across the wide range of distribution. Moreover, the ability to feed on a wide range of host plants (e.g., populations from Yangmingshan National Park (陽明山國家公園) were observed feeding on R. swinhoei Hance and R. corchorifolius L. f. (Rosaceae) (Fig. 14B, C). In addition, females with smaller sclerotized areas of abdominal tergites (Fig. 14C) represent plesiomorphic winged galerucines; those with larger, entirely sclerotized areas of abdominal tergites that provide better protection (Fig. 14D) represent a derived condition.

Figure 15. 

Distribution of Sikkimia species of Taiwan, solid line: 1000 m, broken line: 2000 m; different colors represent different species. Red dots, S. tsoui (after Lee and Bezděk 2016)

Furusawaia Chûjô is a small wingless galerucine genus distributed in China (two species) and Taiwan (five species). Most members of wingless genera are exclusively nocturnal. However, adults of Furusawaia exhibit bizarre behavior with diurnal or nocturnal habits in different individuals of the same species. Adults can often be observed walking on forest trails during the day, while others are active at night. Such behavior may be associated with bicolored elytra (Fig. 16), which may be shared with those bicolored, wingless galerucines, but further study for confirmation is required. Although their food plants are known (Stellaria species (Caryophyllaceae); Fig. 16A), collecting adults by searching food plants at night is difficult. Only 96 specimens were available for the study (Lee and Bezděk 2021).

Figure 16. 

The genus Furusawaia Chûjô A microhabitat of F. lui in Hsinpaiyang (新白楊) B adult of F. jungchani in the daytime, Huakang (華崗) C adult of F. lui at night, Hsinpaiyang (新白楊) D adult of F. tahsiangi in the daytime, Hsuehshan (雪山) E two adults of F. tsoui Lee & Bezdèk at night, Jianqing trail (見晴步道) F adult of F. yosonis at night, Alishan (阿里山) (Lee and Bezděk 2021).

In Taiwan, adults were observed walking or resting on forest trails at low altitudes (1000–2000 m) in northern Taiwan or middle and high altitudes (above 2000 m) in central and southern Taiwan. Most Furusawaia species have broad distributions except for F. jungchani Lee & Bezděk. Two species are sympatric in Taipingshan (太平山). Most adults were collected at lower altitudes (below 2500 m), where they are easily accessible to collectors. Very few individuals were found above 3000 m (Fig. 17).

Figure 17. 

Distribution map of Furusawaia species in Taiwan, solid line: 1000 m, broken line: 2000 m, black areas: 3000 m; different colors represent different species (after Lee and Bezděk 2021).

Apterogaleruca comprises two species, A. hirtihumeralis Chûjô and A. uenoi Kimoto. The former represents a species group that is widespread from lowlands to 2000 m (Fig. 18A–D). Adults and larvae feed on leaves of various species of Urticaceae, including Boehmeria densiflora Hook. & Arn., Elatostema lineolatum Wight var. majus Wedd. (Fig. 18D), E. platyphyllum Wedd., Gonostegia hirta (Blume) Miq., Pellionia radicans (Siebold & Zucc.) Wedd., Pe. scabra Benth., Pilea angulata (Blume) Blume, Pi. melastomoides (Poir.) Wedd., Pi. rotundinucula Hayata, Urtica thunbergiana Siebold & Zucc., and some species of Asteraceae such as Cirsium japonicum DC. var. australe Kitam. (Figs 17C, 18C) and Gynura divaricata (L.) DC. subsp. formosana (Kitam.) F.G. Davies. Members of Apterogaleruca are multivoltine and occur at more localities compared to other wingless galerucines. Physogastric females lay 16–18 eggs in a single egg mass (Fig. 19A). The larvae hatch in three to five days. Larvae feed on leaves, and the larval duration is ~24−26 days. Mature larvae (Fig. 19D) crawl into the soil and build underground chambers for pupation. The pupal stage lasts five to eight days. Apterogaleruca uenoi represents a species group that occurs above 2000 m. Adults of the A. uenoi group (Fig. 18E) differ from those of the A. hirtihumeralis group by possessing smooth bodies and short antennae. Hirtigaleruca is a monotypic genus (type species: H. aptera Chûjô) that inhabits southern Taiwan. This genus may prove to be a species group within Apterogaleruca because of similar morphologies of adults, except for dense hairs on the elytra (Fig. 18F). Moreover, immature stages of Hirtigaleruca are similar to those of Apterogaleruca and share the same host plants with the exception of having fewer eggs in a single egg mass (Fig. 19B). Observations of two or three species of the same species group or different groups at the same locality is typical.

Figure 18. 

Adults of Apterogaleruca and Hirtigaleruca A A. hirtihumeralis, male, collected from Tengchih (藤枝) B different individual collected at same locality C same species, feeds on Cirsium japonicum var. australe, collected from Yangmingshan (陽明山) D same species, female, collected from Neiwan (內灣) E A. uenoi, male, collected from Pilu (畢祿) F Hirtigaleruca aptera, male, collected from Ima (依麻).

Figure 19. 

Immature stages of Apterogaleruca and Hirtigaleruca A eggs of A. hirtihumeralis B eggs of Hirtigaleruca aptera C second-instar larva of A. hirtihumeralis feeding on Cirsium japonicum var. australe, collected from Nanya (南雅) D third-instar larva of A. hirtihumeralis feeding on Elatostema lineolatum var. majus, collected from Huisun (惠蓀).

Unlike most wingless members of Galerucini in Taiwan, individuals of Apterogaleruca inhabit not only mountainous regions but also alpine regions and lowlands. Members of this genus are most widespread and utilize most ecological niches in Taiwan since they are multivoltine and polyphagous in lowlands, and modifications of their external morphology (smooth surface and short antennae) are adapted to alpine regions.

The author has declared that no competing interests exist.

No ethical statement was reported.

This study was supported by the National Science and Technology Council NSTC 112-2313-B-055-001-MY3. Finally, I thank Ron Beenen, Yongying Ruan, and one anonymous reviewer for reviewing the manuscript, and Caroline Chaboo for editorial assistance.

The author solely contributed to this work.

Chi-Feng Lee https://orcid.org/0000-0003-1996-0557

All of the data that support the findings of this study are available in the main text.