Seed dynamics of resprouting shrubs in grassy woodlands: Seed rain,predators and seed loss constrain recruitment potential

Abstract Measuring the fate of seeds between seed production and seedling establishment is critical in understanding mechanisms of recruitment limitation of plants. We examined seed fates to better understand the recruitment dynamics of four resprouting shrubs from two families (Fabaceae and Epacridaceae) in temperate grassy woodlands. We tested whether: (i) pre‐dispersal seed predation affected seed rain; (ii) post‐dispersal seed predation limited seed bank accumulation; (iii) the size of the seed bank was related to seed size; and (iv) viable seeds accumulated in the soil after seed rain. There was a distinct difference in seed production per plant between plant families with the legumes producing significantly more seeds per individual than the epacrids. Seed viability ranged from 43% to 81% and all viable had seed or fruit coat dormancy broken by heat or scarification. Pre‐dispersal predation by Lepidopteran larvae removed a large proportion of seed from the legume seed rain but not the epacrids. Four species of ants (Notoncus ectatomoides, Pheidole sp., Rhytidoponera tasmaniensis and Iridomyrmex purpureus) were major post‐dispersal seed removers. Overall, a greater percentage of Hardenbergia (38%) and Pultenaea (59%) seeds were removed than the fleshy fruits of Lissanthe (14%) or Melichrus (0%). Seed bank sizes were small (<15 seeds m^?2) relative to the seed rain and no significant accumulation of seed in the soil was detected. Lack of accumulation was attributed to seed predation as seed decay was considered unlikely and no seed germination was observed in our study sites. Our study suggests that seed predation is a key factor contributing to seed‐limited recruitment in grassy woodland shrubs by reducing the number of seeds stored in the soil.     

Ant behaviour and seed morphology: a missing link of myrmecochory

Seed dispersal by ants (myrmecochory) is mediated by the presence of a lipid-rich appendage (elaiosome) on the seed that induces a variety of ants to collect the diaspores. When seeds mature or fall onto the ground, these ant species transport them to their nest. After eating the elaiosome, the seed is discarded in nest galleries or outside, in the midden or farther away, where seeds can potentially germinate. The final location of seeds with their elaiosomes removed was evaluated to assess the importance of possible handles (structures that ants can grasp to carry) in transporting ants during re-dispersal experiments of seeds from nests of six species of ants. The results indicate that seeds remained within the nest because the ants were not able to transport them out of the nest. As a consequence of the elaiosome being removed, small ant species could not take Euphorbia characias seeds out of their nests. Only large ant species could remove E. characias seeds from their nests. Attaching an artificial handle to E. characias seeds allowed small ant species to redistribute the seeds from their nests. On the other hand, Rhamnus alaternus seeds that have a natural handle after the elaiosome removal were removed from the nests by both groups of ant species. If a seed has an element that acts as a handle, it will eventually get taken out of the nest. The ants’ size and their mandible gap can determine the outcome of the interaction (i.e. the pattern of the final seed shadow) and as a consequence, could influence the events that take place after the dispersal process.     

Relocation of Croton sonderianus (Euphorbiaceae) seeds by Pheidole fallax Mayr (Formicidae): a case of post-dispersal seed protection by ants?

Although seed dispersal by ants might reduce seed predation near the parent plants, predation on discarded seeds clustered on nest refuse piles may reduce any initial benefit provided by seed removal. Here we examine the fate of Croton sonderianus seeds that were discarded by Pheidole fallax Mayr ants on their nest refuses in caatinga vegetation of northeast Brazil. We collected all seeds discarded in refuse piles of 20 nests and within a radius of 50 cm from their borders, and examined them for evidence of predation. A total of 3,017 seeds were recorded either located in the P. fallax refuse piles (89.1%) or nest vicinity (10.9%). Predation was three fold higher in nest vicinity as compared to refuse piles. By removing seeds from beneath parent plants and relocating then to refuse piles, P. fallax is possibly providing double protection services for C. sonderianus seeds. Our findings represent the first evidence for predator-avoidance as benefit for plants resulting from ant seed-dispersal in the neotropics.     

Seed handling behaviours of native and invasive seed‐dispersing ants differentially influence seedling emergence in an introduced plant

相似文献   

Assessing ant seed predation in threatened plants: a case study

Erodium paularense is a threatened plant species that is subject to seed predation by the granivorous ant Messor capitatus. In this paper we assessed the intensity and pattern of ant seed predation and looked for possible adaptive strategies at the seed and plant levels to cope with this predation. Seed predation was estimated in 1997 and 1998 at the population level by comparing total seed production and ant consumption, assessed by counting seed hulls in refuse piles. According to this method, ant seed predation ranged between 18% and 28%. A more detailed and direct assessment conducted in 1997 raised this estimate to 43%. In this assessment spatial and temporal patterns of seed predation by ants were studied by mapping all nest entrances in the studied area and marking the mature fruits of 109 reproductive plants with a specific colour code throughout the seed dispersal period. Intact fruit coats were later recovered from the refuse piles, and their mother plants and time of dispersal were identified. Seeds dispersed at the end of the dispersal period had a greater probability of escaping from ant seed predation. Similarly, in plants with late dispersal a greater percentage of seeds escaped from ant predation. Optimum dispersal time coincided with the maximum activity of granivorous ants because, at this time, ants focused their harvest on other plant species of the community. It was also observed that within-individual seed dispersal asynchrony minimised seed predation. From a conservation perspective, results show that the granivorous ant–plant interaction cannot be assessed in isolation and that the intensity of its effects basically depends on the seed dispersal pattern of the other members of the plant community. Furthermore, this threat must be assessed by considering the overall situation of the target population. Thus, in E. paularense, the strong limitation of safe-sites for seedling establishment reduces the importance of seed predation.     

Odor of achlorophyllous plants’ seeds drives seed‐dispersing ants

Seed dispersal by ants is an important means of migration for plants. Many myrmecochorous plants have specialized appendages in their seeds called elaiosome, which provides nutritional rewards for ants, and enable effective seed dispersal. However, some nonmyrmecochorous seeds without elaiosomes are also dispersed by ant species, suggesting the additional mechanisms other than elaiosomes for seed dispersal by ants. The seeds of the achlorophyllous and myco‐heterotrophic herbaceous plant Monotropastrum humile are very small without elaiosomes; we investigated whether odor of the seeds could mediate seed dispersal by ants. We performed a bioassay using seeds of M. humile and the ant Nylanderia flavipes to demonstrate ant‐mediated seed dispersal. We also analyzed the volatile odors emitted from M. humile seeds and conducted bioassays using dummy seeds coated with seed volatiles. Although elaiosomes were absent from the M. humile seeds, the ants carried the seeds to their nests. They also carried the dummy seeds coated with the seed volatile mixture to the nest and left some dummy seeds inside the nest and discarded the rest of the dummy seeds outside the nest with a bias toward specific locations, which might be conducive to germination. We concluded that, in M. humile seeds, volatile odor mixtures were sufficient to induce seed‐carrying behavior by the ants even without elaiosomes.     

Adaptive advantages of myrmecochory: the predator-avoidance hypothesis tested over a wide geographic range

The predator‐avoidance hypothesis states that once released from the parent plant, myrmecochorous seeds are rapidly taken by ants to their nests, where they are protected from predators. Previous studies conducted to test this hypothesis have frequently neglected two major aspects necessary for its verification: 1) the influence of processes acting after the seed release and 2) the spatial evenness of such processes. Thus, large‐scale variations in the mechanisms acting beyond seed release, and possibly influencing seed escape from predators, remain poorly documented. Here, we present the results of a post‐dispersal seed‐removal experiment on the myrmecochorous herb Helleborus foetidus, aimed at verifing the predator‐avoidance hypothesis by considering two key post‐release aspects of seed fate: seed destination (dispersed or nondispersed) and seed burial (buried or not buried). Experiments were performed in four different regions in the Iberian Peninsula. After three days of exposure of seeds to the main predator (fieldmice Apodemus sylvaticus), ca 30% of the seeds were removed. Seed destination affected the proportion of seeds escaping predation, but the sign, magnitude and statistical significance of the effect varied among the geographical regions. In the southern region (Cazorla), seeds dispersed in ant nests or intermediate destinations suffered scarcely any predation, but seeds under reproductive‐age plants experienced losses ca 50%. Conversely, in the northern region (Caurel), seeds in nests suffered significantly greater losses than seeds under plants or intermediate destinations, suggesting that nests were especially unsafe destinations. Seed burial had a strong impact on seed escape from predators, and its effect was highly consistent among geographical regions. In view of the consistency of its effect at different spatial scales, seed burial was a more general mechanism for predation avoidance than seed relocation to ant nests, which was habitat‐ and/or ant‐species‐dependent. Our results thus only partially support the predator‐avoidance hypothesis for the evolution of myrmecochory.     

The role of ants and mammals in dispersal and post-dispersal seed predation of the shrubs Grevillea (Proteaceae)

The role seed predators play in influencing the dynamics of plant populations has been little studied in Australia. The interaction of ant dispersal and seed predation on the soil seedbank in six shrubby species of Grevillea from the Sydney region of southeastern Australia was examined in selective exclusion experiments, seed array trials and placement of single seeds on the ground.Two distinct seed types in Grevillea were examined and different seed dispersal and post-dispersal seed predation patterns were associated with each: (a) seeds lacking an elaiosome were not attractive to ants and annual seed losses of between 82 and 95% were found in vegetation unburnt for greater than 8 years. Native rodents, Rattus fuscipes, and macropods, Wallabia bicolor, were responsible for these seed losses; (b) seeds with an elaiosome were rapidly handled by ants. Two functional types of ants were recognised. Most encounters were by ants that were small (Local) relative to seed size and these ants simply removed the elaiosome in situ or moved seeds only small distances (<20 cm). Some 0–24% of ant/seed encounters were by large (Removalist) ant species that were capable of moving seeds back to nests. In addition, Rattus fuscipes and Wallabia bicolor consumed at least 32–68% of seeds of Grevillea species with an elaiosome.Ants may reduce the overall levels of seed predation where seeds moved by Removalist ant species escape predation and are deposited in safe sites, hence allowing more seeds to reach the persistent soil seedbank. Mammals do not consume all seeds when ants are excluded, allowing for the potential for some seed escape from predation after seeds are discarded by Local ant species.     

Myrmecochory in Polygala vulgaris L., Luzula campestris (L.) DC. and Viola curtisii Forster in a Dutch dune area

Summary Seed dispersal by ants in Polygala vulgaris, Luzula campestris and Viola curtisii was studied in a primary dune valley on the island of Terschelling, The Netherlands. Normally developed seeds of all three species are taken by the ants into their nests. The ants show a distinct preference for the seeds of the specialized myrmecochore Polygala vulgaris, as compared with the two diplochorous species. It could be demonstrated that the elaiosome is the attractive part of the seed. Mapping studies demonstrate that the dispersal of the seeds by ants has a marked effect on the distribution pattern of the standing population of Polygala and Viola. Adult plants are often found on or close to the active nest mounds of all ant species present, while the growing sites of juvenile individuals and seedlings are practically restricted to the nest environment. The nests of two of the seed-dispersing ant species, viz., those of Lasius niger and Tetramorium caespitum, show differences in soil chemistry with the surroundings. The ant nests are significantly richer in some essential plant macronutrients, such as phosphate, potassium and nitrate. The advantage of myrmecochory in the dune area of Terschelling is discussed.     

Seed dispersal by ants in the semi-arid Caatinga of North-East Brazil

BACKGROUND AND AIMS: Myrmecochory is a conspicuous feature of several sclerophyll ecosystems around the world but it has received little attention in the semi-arid areas of South America. This study addresses the importance of seed dispersal by ants in a 2500-km(2) area of the Caatinga ecosystem (north-east Brazil) and investigates ant-derived benefits to the plant through myrmecochory. METHODS: Seed manipulation and dispersal by ants was investigated during a 3-year period in the Xingó region. Both plant and ant assemblages involved in seed dispersal were described and ant behaviour was characterized. True myrmecochorous seeds of seven Euphorbiaceae species (i.e. elaiosome-bearing seeds) were used in experiments designed to: (1) quantify the rates of seed cleaning/removal and the influence of both seed size and elaiosome presence on seed removal; (2) identify the fate of seeds dispersed by ants; and (3) document the benefits of seed dispersal by ants in terms of seed germination and seedling growth. KEY RESULTS: Seed dispersal by ants involved one-quarter of the woody flora inhabiting the Xingó region, but true myrmecochory was restricted to 12.8 % of the woody plant species. Myrmecochorous seeds manipulated by ants faced high levels of seed removal (38-84 %) and 83 % of removed seeds were discarded on ant nests. Moreover, seed removal positively correlated with the presence of elaiosome, and elaiosome removal increased germination success by at least 30 %. Finally, some Euphorbiaceae species presented both increased germination and seedling growth on ant-nest soils. CONCLUSIONS: Myrmecochory is a relevant seed dispersal mode in the Caatinga ecosystem, and is particularly frequent among Euphorbiaceae trees and shrubs. The fact that seeds reach micro-sites suitable for establishment (ant nests) supports the directed dispersal hypothesis as a possible force favouring myrmecochory in this ecosystem. Ecosystems with a high frequency of myrmecochorous plants appear not to be restricted to regions of nutrient-impoverished soil or to fire-prone regions.     

Assessing ant seed predation in threatened plants: a case study

Erodium paularense is a threatened plant species that is subject to seed predation by the granivorous ant Messor capitatus. In this paper we assessed the intensity and pattern of ant seed predation and looked for possible adaptive strategies at the seed and plant levels to cope with this predation. Seed predation was estimated in 1997 and 1998 at the population level by comparing total seed production and ant consumption, assessed by counting seed hulls in refuse piles. According to this method, ant seed predation ranged between 18% and 28%. A more detailed and direct assessment conducted in 1997 raised this estimate to 43%. In this assessment spatial and temporal patterns of seed predation by ants were studied by mapping all nest entrances in the studied area and marking the mature fruits of 109 reproductive plants with a specific colour code throughout the seed dispersal period. Intact fruit coats were later recovered from the refuse piles, and their mother plants and time of dispersal were identified. Seeds dispersed at the end of the dispersal period had a greater probability of escaping from ant seed predation. Similarly, in plants with late dispersal a greater percentage of seeds escaped from ant predation. Optimum dispersal time coincided with the maximum activity of granivorous ants because, at this time, ants focused their harvest on other plant species of the community. It was also observed that within-individual seed dispersal asynchrony minimised seed predation. From a conservation perspective, results show that the granivorous ant–plant interaction cannot be assessed in isolation and that the intensity of its effects basically depends on the seed dispersal pattern of the other members of the plant community. Furthermore, this threat must be assessed by considering the overall situation of the target population. Thus, in E. paularense, the strong limitation of safe-sites for seedling establishment reduces the importance of seed predation.     

小果野芭蕉种子散布和不同时空尺度上种子被捕食格局

 以分布在云南西双版纳地区的大型先锋草本植物小果野芭蕉(Musa acuminata)为研究材料,研究其种子初次散布过程和不同时空尺度上种子被 捕食格局。小果野芭蕉的成熟果实有75%在夜间被取食和传播,在白天消失的果实则占25%。蝙蝠是其最主要的种子传播者,鸟类在其种子传播 过程中也起到一定的作用。人工摆放种子试验结果显示小果野芭蕉种子的主要转移者是小型啮齿类(鼠类)和蚁类：在开放处理下3 d后转移率为 86%,排除蚁类(鼠类可进入)处理下种子转移率为69%以及排除鼠类(蚂蚁可进入)处理下种子被转移率为56%。季节、地点和生境均显著影响人工 摆放种子被转移强度：雨季显著高于旱季(p<0.001), 野芭蕉生境显著高于与其相连的自然森林和荒地(p<0.001),在人为干扰较少的补蚌自然 保护区显著低于西双版纳热带植物园和新山,而后两者之间并无显著差异(p>0.05)。同时,地点和生境以及季节、地点和生境都有显著的交互 作用。与相邻的森林和荒地相比,野芭蕉群落中种子被鼠类捕食的强度最大且受蚁类二次转移的比例最少,森林和荒地中种子被鼠类捕食的强 度相对较小且蚁类对种子的二次转移比例较高,从而更好地帮助种子逃避鼠类捕食。因此,依赖于食果动物(主要是蝙蝠, 也包括鸟类)的初次 散布是小果野芭蕉种子逃避捕食的关键。     

Endophytic fungi alter foraging and dispersal by desert seed-harvesting ants

Endophytic fungi are thought to interact mutualistically with host plants by producing alkaloid metabolites that deter herbivory. Since such fungi are transmitted via seed in some grasses, the presence of endophytes may also protect plants from seed predators. We conducted seed choice experiments for two dominant seed harvesting ants, Pogonomyrmex rugosus in the Sonoran desert and Pogonomyrmex occidentalis at a higher elevation, riparian zone in Arizona, USA. Non-infected fescue (Festuca arundinacea) seeds and seeds infected with the endophytic fungus, Acremonium coenophialum, were presented to ant colonies in three different populations. Infected seeds were harvested less frequently than non-infected seed for the two populations of Pogonomyrmex rugosus but not for the population of Pogonomyrmex occidentalis. We also a conducted seed dispersal experiment for one population of Pogonomyrmex rugosus. Of the seeds that were harvested, most of the colonies discarded more infected seeds into refuse piles than expected by chance. Seeds discarded into refuse piles have greater germination success than surrounding areas. The most important interaction of endophytes and grasses may be deterrence of seed predation and enhancing the probability of germinating in favorable sites, since these processes directly increase plant fitness.     

Seed dispersal in Erythronium dens-canis L. (Liliaceae): variation among habitats in a myrmecochorous plant

Erythronium dens-canis is a geophyte which produces a single flower each season. The fruits produce small seeds with relatively large elaiosomes. We performed experiments to investigate primary and secondary seed dispersal mechanisms of this species in different habitats in the western part of the Cantabrian Range in northwest Spain. Sticky traps were used to measure primary dispersal of seeds up to 0.5 m from mother plants. Seed cafeteria experiments were performed in different habitats to examine the role of ants and rodents in secondary seed transport and seed predation. Our results indicate that: (a) primary seed dispersal is positively skewed (99% of seeds fall within 20 cm of the mother plant) and seed dispersal distances vary significantly among plants; (b) secondary dispersal is exclusively by myrmecochory, although the proportion of seeds removed by ants differs significantly among habitats; (c) ant species composition and abundances vary among habitats; and (d) freshly dropped seeds are more likely to be removed than seeds that have begun to dry out. We conclude that secondary dispersal of seeds is greatly influenced by habitat but not by small-scale microhabitat. This revised version was published online in June 2006 with corrections to the Cover Date.     

DUAL FUNCTION OF THE ELAIOSOME OF CORYDALIS AUREA (FUMARIACEAE): ATTRACTION OF DISPERSAL AGENTS AND REPULSION OF PEROMYSCUS MANICULATUS,A SEED PREDATOR

It has been suggested that one of the selective advantages of ant dispersal is the burial of seeds in ant nests where predators such as small rodents cannot find them. The elaiosomes of Corydalis aurea (Fumariaceae) are extremely attractive to ants, which assiduously gather the seeds and take them to nests. However, seed production commonly exceeds the gathering capacity of ants so that seeds accumulate beneath the parent plants. In spite of this, no signs of rodent predation are evident. Experiments with a major seed predator, the deer mouse Peromyscus maniculatus, show that when given the choice of seeds with and without elaiosomes, the mice consume significantly more seeds without elaiosomes. This remains true whether or not the intact seeds bear fresh, moist elaiosomes or dry, withered ones. Our experiments strongly suggest that the elaiosome has a dual function, the attraction of the ant seed dispersers and the repulsion of seed predators.     

First report of seed dispersal by ants in Dicentra peregrina (Papaveraceae), an alpine plant in the Japanese Alps

Seed dispersal by ants, known as myrmecochory, is commonly observed among various plant taxa. The seeds of these plants have an elaiosome to attract ants. In Japan, myrmecochory has been well studied in several lowland plant species, but not in highland plant species that grow above the tree line. We investigated whether the seeds of Dicentra peregrina, known as the “queen of the alpine plants” in Japan, are carried by Formica gagatoides ants at 2510 m a.s.l. on Mt Norikura, Kita‐Alps, Japan. We observed F. gagatoides workers picking up D. peregrina seeds by grasping the elaiosome and carrying the seeds into their nests. We inferred from the observed ant behavior and the seed morphology that D. peregrina is a myrmecochorous species.     

Indirect effects of granivory by harvester ants: plant species composition and reproductive increase near ant nests

Summary Of 36 plant species surveyed, 6 were significantly associated with nests of the desert seed-harvester ant Veromessor pergandei or Pogonomyrmex rugosus; two other plant species were significantly absent from ant nests. Seeds of two common desert annuals, Schismus arabicus and Plantago insularis, realize a 15.6 and 6.5 fold increase (respectively) in number of fruits or seeds produced per plant growing in ant nest refuse piles compared to nearby controls. Mass of individual S. arabicus seed produced by plants growing in refuse piles also increased significantly. Schismus arabicus, P. insularis and other plants associated with ant nests do not have seeds with obvious appendages attractive to ants. Dispersal and reproductive increase of such seeds may represent a relatively primitive form of ant-plant dispersal devoid of seed morphological specializations. Alternatively, evolution of specialized seed structures for dispersal may be precluded by the assemblage of North American seed-harvester ants whose workers are significantly larger than those ants normally associated with elaiosome-attached seed dispersal. Large worker size may permit consumption of elaiosome and seed.     

Unexpected relationships and valuable mistakes: non‐myrmecochorous Prosopis dispersed by messy leafcutting ants in harvesting their seeds

Abstract Ants generally disperse seeds while feeding on fruits or structures attached to the seed. Seed dispersal as a by‐product of seed predation (dyszoochory) was recognized in specialized harvester ants, but not in ants predating seeds opportunistically. Leafcutting ants are the main herbivores in much of the Neotropics, and they have been reported to remove fruits and seeds, but their role as seed predators and dispersers has not been acknowledged. Prosopis flexuosa D.C. (Fabaceae, Mimosoideae) is the most abundant tree species in the central Monte Desert, Argentina, and it is likely to depend on secondary animal dispersal. Mammalian frugivores are usually considered its main dispersers, but the opportunity for dispersal may be small since the removal of fruits and seeds by seed predators is very intense. The objective of this study was to identify which ant species interact with P. flexuosa fruits and to evaluate their relative importance as seed predators and dispersers. In a field experiment, whole and segmented pods were offered and several ant species exploiting the fruits were identified. Additionally, all pod segments remaining around nests of the three ant species able to remove them (the leafcutters Acromyrmex lobicornis Emery and Acromyrmex striatus Roger, and Pheidole bergi Mayr) were examined during and after the P. flexuosa primary dispersal season. Up to 753 pod segments and 90 sound seeds were found accumulated in a circle of 1 m radius over nests of A. lobicornis, and even more in an examined trail. Acromyrmex striatus left a smaller proportion of sound seeds and P. bergi left a smaller number of pod segments. All tendencies were similar during shorter known periods of accumulation. Leafcutting ants are acting as important seed predators, and ‘by mistake’ may be dispersing a key non‐myrmecochorous tree. This is an unexplored path in the seed dispersal cycle of P. flexuosa that challenges the tendency to predict interactions based on classifications made with other goals.     

Dispersal for distance? Acacia ligulata seeds and meat ants Iridomyrmex viridiaeneus

Abstract Ant seed dispersal distances are typically small, averaging less than 1 m in published studies. Here, a new record (180 m) for ant seed dispersal distance is reported, and preliminary observations are made on the interaction between meat ants Iridomyrmex viridiaeneus Viehmeyer (Hymenoptera: Formicidae) and diaspores of the sandhill wattle, Acacia ligulata A. Cunn. ex Benth. (Fabaceae) in Kinchega National Park, New South Wales (NSW), Australia. Iridomyrmex viridiaeneus moved diaspores over distances of 7–180 m (mean 93.9 m) from the source trees to their nests, removed the arils underground and discarded the seeds over a 3000‐m² area surrounding the nest. A germination trial determined that the viability of discarded seeds was 40%, with 80% of the viable seeds in a dormant condition. Although the cumulative effects of I. viridiaeneus on A. ligulata recruitment require further investigation, this study and others raise the possibility that myrmecochorous systems in the Australian arid zone may be characterized by longer dispersal distances than those in other parts of the world. Long‐distance seed movement by ants lends credence to the hypothesis that distance dispersal (in contrast to directed dispersal) could be of benefit to myrmecochorous plants.     

Seed dispersal of the hemiparasitic plant Thesium chinense by Tetramorium tsushimae and Pristomyrmex punctatus

Heterotrophic plants normally produce a vast number of dust‐like seeds containing minimal energy reserves, which are usually wind dispersed. However, some heterotrophic species have evolved adaptive strategies to use zoochorous seed dispersal. Seed dispersal by ants, known as myrmecochory, is one of the most widespread animal dispersal systems and has been reported in a diverse range of plant taxa. However, the combination of myrmecochory and heterotrophy seems to be very rare. Here I report the discovery of myrmecochory in the hemiparasitic plant Thesium chinense by Tetramorium tsushimae and Pristomyrmex punctatus. Myrmecochory would be an advantageous dispersal system for T. chinense because its fruits are quickly transferred to the ants' nests, which provide a refuge from the seed predator Canthophorus niveimarginatus. Myrmecochory is also potentially beneficial for T. chinense, as the nests of these ants are frequently located close to poaceous plants, which are the preferred hosts.