High occurrence of colony fusion in a European population of the American termite Reticulitermes flavipes

The coexistence of multiple unrelated reproductives within social insect colonies decreases the relatedness among colony members and therefore challenges kin selection theory. This study investigated the colony genetic structure of a French introduced population of the American subterranean termite Reticulitermes flavipes by analyzing genotypes at eight microsatellite loci and at one mtDNA region. Results revealed that all colonies contained numerous related secondary reproductives, and that 31% of colonies possessed more than two unrelated reproductives. The presence of several unrelated reproductives within colonies of this species is commonly assumed to result from colony fusion. Although such a high occurrence of colony fusion is the highest ever observed in a termite population, it is probable that the available methodology underestimated the detection of colony fusion in French populations. Overall, these results suggest that French colonies might differ strongly from the great majority of American colonies in their capacity to produce secondary reproductives as well as in their ability to merge. The nature and evolutionary origin of these population differences are discussed.     

Turnover in termite colonies: a genetic study of colonies ofIncisitermers schwarzi headed by replacement reproductives

Summary Analysis of allozyme markers was carried out on 16 colonies of the termiteIncisitermes schwarzi in which one or both primary (founding) reproductives had been replaced by secondary reproductives. About one-quarter of field-collected colonies have replacement reproductives, and the genetic data suggest that in most of these a single replacement event had occurred. Genetic evidence for a second replacement event was found in one colony. Genetic analysis of the offspring allowed the following conclusions: (1) Soldiers are a relatively long-lived caste, so that even in colonies in which all other members have been replaced by offspring of the secondary reproductives, the soldiers remain the offspring of the primary reproductives; and (2) when primary reproductives are replaced by secondary reproductives, the nosoldier offspring of the former are completely replaced by those of the latter over a period of about two or three years, probably as a result of the normal maturation of colony members (workers, nymphs, and alates). The results provide no evidence for the existence of a true sterile worker caste in this species.     

The origins and relatedness of multiple reproductives in colonies of the termite Nasutitermes corniger

Colonies of the termite Nasutitermes corniger often contain multiple reproductive queens and kings. We used double-strand conformation polymorphism (DSCP) analysis of mitochondrial DNA (mtDNA) to determine the probable origins of co-occurring reproductives. Colonies differed in queen and king number, in the number of nests containing reproductives, and in the genetic relationships among reproductives. Most of the 44 colonies contained a single pair of maternally unrelated reproductives. In the two single-nest colonies with a pair of queens, the two queens differed in mtDNA haplotype, suggesting nest-founding by unrelated queens. In the seven single-nest colonies with larger numbers of reproductives (11–49), all reproductives shared the same haplotype, a pattern consistent with replacement of a single pair by several offspring. As predicted by theory, the number of coexisting queens was greater for replacement reproductives than for co-foundresses. Several complex colonies contained multiple queens of two or more haplotypes distributed among several interconnected nests. This indicates that several matrilines can persist within a colony through one or more generations of budding and replacement, a hypothesis confirmed by orphaning experiments. The various modes of termite colony formation rival the diversity seen in ant species and demonstrate the remarkable convergence of behaviours between the two groups.     

Worker size in the formosan subterranean termite in relation to colony breeding structure as inferred from molecular markers

The Formosan subterranean termite, Coptotermes formosanus Shiraki, is an invasive species that originated in China and has been introduced to Hawaii and the U.S. mainland. Colonies are headed either by a pair of reproductives (simple families) or by varying numbers of inbreeding reproductives (extended families), and therefore have variable degrees of inbreeding. Worker size also varies among colonies of Formosan termites. We tested whether variation in worker size can be explained by the breeding system. Workers were collected from colonies from three geographically separated populations (China, Hawaii, and Louisiana), and body weight and head size were measured. Microsatellite genotyping was used to establish whether colonies were simple or extended families and to determine the heterozygosity of workers and their degree of inbreeding relative to their colony (F (IC), sensitive to the number of reproductives). All Chinese colonies contained multiple inbreeding neotenics. In Hawaii, 37% of the colonies were simple families and 63% were extended families, both having considerable degrees of inbreeding. In Louisiana, 57% of the colonies were simple families, which were mostly headed by unrelated pairs, and 43% were extended families. In simple families, size and body weight of workers were not associated with F (IC) or heterozygosity. In extended families of two populations, both size parameters were negatively correlated with F (IC); however, heterozygosity was not associated with worker size in any of the populations. This suggests that the number of reproductives within colonies has a stronger influence on worker size than the individuals' genetic diversity in Formosan subterranean termite colonies.     

The breeding system and population structure of the termite Reticulitermes grassei in Southwestern France

We assessed colony and population structure in three French populations of the termite Reticulitermes grassei using eight polymorphic microsatellite loci. Although most colonies contained the offspring of multiple, highly related replacement reproductives (complex families), some contained the offspring of a single pair of reproductives (simple families), and the proportion of such colonies varied across populations. Populations also showed variability in the numbers of reproductives within complex families; the F-statistics of these families in one population were consistent with having upwards of 100 replacement reproductives, while in another population these colonies contained fewer than 10 pairs of reproductives. Colony boundaries in all populations were well defined, in spite of reports of a widespread breakdown in nestmate recognition and unicolonial populations of R. grassei from these regions in France. A second unexpected finding was a lack of significant isolation by distance among colonies within populations, indicating that colony reproduction by budding was rare or absent. The lack of this form of colony reproduction even within populations where it is expected to be common suggested that the propensity for colony budding may not be as common as suggested by the literature.     

Workers do not mediate the inhibitory power of queens in a termite, <Emphasis Type="Italic">Reticulitermes speratus</Emphasis> (Isoptera,Rhinotermitidae)

In social insects, the caste systems are based on reproductive division of labor; queens specialize in reproduction and workers primarily maintain the colony. Recently, a volatile pheromone containing n-butyl-n-butyrate and 2-methyl-1-butanol was identified as a termite queen pheromone that inhibits the differentiation of female neotenic reproductives (secondary queens). Although this volatile inhibitory pheromone regulates caste differentiation directly, the method by which it reaches members without direct contact with the queen in large colonies is not well understood. Therefore, additional mechanisms of indirect communication must exist, such as worker-mediated queen signal transport. We found that workers exposed to female reproductives did not mediate queens’ inhibitory signal in a termite Reticulitermes speratus. The experiment assessed worker transfer from direct to indirect contact groups and determined that the differentiation of new female reproductives in the indirect contact groups was not influenced by the direct contact groups, whereas direct contact with functional female reproductives and artificial queen pheromone did suppress neotenic differentiation. This suggests that worker transfer of the queen signal is unlikely and that for colony-wide inhibition direct contact by the majority of infertile members with reproductives or eggs, which emit the same volatiles as female reproductives, is necessary within a certain time interval.     

Colony and population genetic structure of the Formosan subterranean termite,Coptotermes formosanus,in Japan

Subterranean termites have unusual plasticity in their breeding systems. As a result of their cryptic foraging and nesting habits, detailed information on the numbers and types of reproductive individuals in colonies has been difficult to obtain. In this study, we used microsatellite markers to infer the major features of the breeding system of the Formosan subterranean termite, Coptotermes formosanus, in southern Japan, where it is believed to have been introduced from China. A total of 30 colonies was sampled from two islands (Kyushu and Fukue) located 100 km apart. Twenty workers from each colony were genotyped at six microsatellite loci. Analysis of worker genotypes within colonies indicated that 27 colonies (90%) were simple (Mendelian) families. The remaining three colonies, all from Kyushu, were consistent with being extended families having begun as simple families but being currently headed by multiple neotenic (secondary) reproductives descended from the original king and queen. Workers from simple families in both populations were significantly inbred (FIT = 0.10 for Kyushu and 0.46 for Fukue) and highly related to their nestmates (coefficient of relatedness, r = 0.59 for Kyushu and 0.77 for Fukue), suggesting that many simple-family colonies were headed by closely related reproductives, especially in the Fukue population. This conclusion is supported by the high coefficient of relatedness between nestmate reproductives in simple-family colonies (r = 0.23 for Kyushu and 0.61 for Fukue) based on genotypes inferred from their worker offspring. There was moderate genetic differentiation (FST = 0.12) between the two populations, suggesting rather restricted gene flow between them. There was no significant isolation by distance among colonies, as might be expected given the limited dispersal of reproductives, presumably because of the frequent movement of colonies by humans. Finally, there was no evidence of a recent bottleneck, a finding possibly consistent with the more than 300-year history of this species in Japan.     

Extreme genetic mixing within colonies of the wood-dwelling termite Kalotermes flavicollis (Isoptera,Kalotermitidae)

The existence of altruism in social insects is commonly attributed to altruistic individuals gaining indirect fitness through kin selection. However, recent studies suggest that such individuals might also gain direct fitness through reproduction. Experimental studies on primitive wood-dwelling termites revealed that colony fusion often causes the death of primary reproductives (queen and king), allowing opportunities for workers to inherit the nest by developing into replacement reproductives (neotenics). Therefore, colony fusion has been proposed as an important factor that may have favoured sociality in termites. However, whether colony fusion occurs frequently in natural populations of wood-dwelling termites remains an open question. We analysed eleven colonies of the wood-dwelling termite Kalotermes flavicollis (Kalotermitidae), using two mitochondrial and five nuclear microsatellite markers. Nine of eleven colonies (82%) were mixed families, with offspring of three or more primary reproductives. To our knowledge, this result represents the highest frequency of mixed-family colonies ever reported in termites. Moreover, genetic mixing of colonies appeared extreme in two ways. First, the number of haplotypes per colony was exceptionally high (up to nine), indicating that colonies were composed of multiple queens' offspring. Second, some mixed-family colonies included individuals belonging to two highly divergent genetic lineages. F-statistics and relatedness values suggest that mixed-family colonies most likely result from colony fusion, giving support to the accelerated nest inheritance theory. These findings raise important questions about the mode of foundation of mixed-family colonies and the evolutionary forces that maintain them within populations.     

X‐ray computed tomography reveals that intraspecific competition promotes soldier differentiation in a one‐piece nesting termite

Investment in soldier production in eusocial lineages involves a trade‐off between maintenance costs and defense benefits. Termites are eusocial insects that live in colonies organized into three castes: primary reproductives, soldiers, and workers or pseudergates. Neotermes chilensis (Blanchard) (Isoptera: Kalotermitidae) is a one‐piece nesting termite that nests and forages in a single piece of wood. Two scenarios may be of importance in a defense context of one‐piece nesting termites: during swarms, when colonies may be invaded by winged termites (alates) in search of a place to found a new colony, and when colonies of conspecifics are present within the same substrate. It was hypothesized that the ratio of soldiers to non‐soldiers would be higher at the onset of the swarming period and in substrates bearing more than one termite colony. A method based on X‐ray computed tomography (CT) was developed to study gallery connectivity in colonies of N. chilensis and caste composition within colonies. Computed tomography allowed the digital reconstruction of the galleries within the substrate, even when they belonged to different colonies, and was effective in distinguishing termites from substrate, and soldiers from reproductives and pseudergates. Using CT, the ratio of soldiers to non‐soldiers was shown to be highest in colonies within multicolonial scapes (i.e., neighboring colonies were present in the same substrate) during the swarming season, thus supporting our initial hypotheses. These results constitute a unique example of induced defenses arising from intraspecific interactions in termites.     

Comparative study of incipient colony development in the Formosan subterranean termite, <Emphasis Type="Italic">Coptotermes formosanus</Emphasis> Shiraki (Isoptera,Rhinotermitidae)

Summary The Formosan subterranean termite, Coptotermes formosanus Shiraki is the most destructive, difficult to control and economically important species of termite in the southern United States. At present, no information is available on the genetic relatedness of primary Formosan subterranean termite reproductives that establish new colonies. Information on survivorship and fitness components of primary reproductives from different sibships (sibling or nonsibling) is helpful to our understanding of biological and ecological characteristics of different breeding generations in C. formosanus. The present study examined the effects of sibship and colony origin on growth and mortality of incipient colonies of C. formosanus. Seven stock colonies of C. formosanus were collected in 1996 through 1997 in New Orleans and Lake Charles, La, USA. A total of 338 incipient colonies of sibling pairs or nonsibling pairs of C. formosanus were set up. The study indicated that mate relatedness significantly affected mortality and fitness. Nonsibling mates suffered significantly higher mortality than sibling mates originated from New Orleans. However, the decreased success of outbred mates was offset by an increased fecundity compared to inbred colonies over time. Both sibling- and nonsibling-founded colonies from Lake Charles had a significantly higher survival rate than did colonies from New Orleans. Colonies from Lake Charles also produced a significantly higher number of larvae/workers than colonies from New Orleans. The mismatch of habits by mates from different locations and the potential for greater disease risks may be associated with higher mortality in outbred pairs. However, heterozygous offspring of outbred pairs probably have increased genetic variation, which provides greater adaptation potential, thus making the colony more robust in the face of environmental fluctuations.Received 11 March 2002; revised 26 February 2003; accepted 14 March 2003.     

Association between caste and genotype in the termite Mastotermes darwiniensis Froggatt (Isoptera: Mastotermitidae)

Abstract Termite workers and soldiers differ markedly in their morphology and behaviour. We sought evidence for genetic influences on caste determination in the giant northern termite, Mastotermes darwiniensis , by investigating if workers and soldiers from the same colony differed genetically. The genotypes of 795 termites from 11 distinct colonies were assayed at six polymorphic microsatellite loci. We found that the multilocus genotypes of workers and soldiers from 8 of the 11 colonies did not differ significantly. Thus, the majority of the data provided no evidence for a genetic association with caste in workers and soldiers of M. darwiniensis . However, the genotype frequencies of workers and soldiers from three colonies differed, suggesting that genotype is occasionally associated with caste in this species. The genetic differentiation of castes within these colonies could reflect differences in the propensities of termites with distinct genotypes to develop into particular castes and provide a selective advantage to colonies headed by multiple reproductives.     

圆唇散白蚁补充生殖蚁的类型与建群能力

摘要: 【目的】为了探讨圆唇散白蚁Reticulitermes labralis补充生殖蚁对巢群稳定和发展的作用。【方法】对野外巢群进行调查研究, 及对婚飞成虫通过雌雄配对与补充生殖蚁隔离巢群进行人工饲养的对比研究。【结果】在野外巢群只发现1对原始蚁王蚁后, 而补充生殖蚁的数量最多可达到689头/巢。圆唇散白蚁有3种类型的补充生殖蚁, 即由工蚁转化来的无翅型补充生殖蚁、若蚁转化来的翅芽型补充生殖蚁和末龄若蚁羽化来的拟成虫型补充生殖蚁。实验室条件下婚飞配对群体和隔离群体建群1个月后的存活率分别为64%和96%。建巢初期婚飞配对群体的子代数目增长缓慢, 2个月时的群体数量为6.3±1.54, 10个月时的群体数量也仅为8.4±1.47; 而隔离建群补充生殖蚁2个月时的群体数量为52.4±6.44, 10个月时的群体数量为164.3±20.85, 都高于婚飞配对群体。 此外, 野外巢群的补充蚁后跟原始蚁后一样都具有发达的卵巢。【结论】在圆唇散白蚁中补充生殖蚁是白蚁巢群主要的繁殖力量, 也是建立新巢群的重要繁殖品级。     

Spatial structuring of the population genetics of a European subterranean termite species

In population genetics studies, detecting and quantifying the distribution of genetic variation can help elucidate ecological and evolutionary processes. In social insects, the distribution of population‐level genetic variability is generally linked to colony‐level genetic structure. It is thus especially crucial to conduct complementary analyses on such organisms to examine how spatial and social constraints interact to shape patterns of intraspecific diversity. In this study, we sequenced the mitochondrial COII gene for 52 colonies of the subterranean termite Reticulitermes grassei (Isoptera: Rhinotermitidae), sampled from a population in southwestern France. Three haplotypes were detected, one of which was found exclusively in the southern part of the study area (near the Pyrenees). After genotyping 6 microsatellite loci for 512 individual termites, we detected a significant degree of isolation by distance among individuals over the entire range; however, the cline of genetic differentiation was not continuous, suggesting the existence of differentiated populations. A spatial principal component analysis based on allele frequency data revealed significant spatial autocorrelation among genotypes: the northern and southern groups were strongly differentiated. This finding was corroborated by clustering analyses; depending on the randomized data set, two or three clusters, exhibiting significant degrees of differentiation, were identified. An examination of colony breeding systems showed that colonies containing related neotenic reproductives were prevalent, suggesting that inbreeding may contribute to the high level of homozygosity observed and thus enhance genetic contrasts among colonies. We discuss the effect of evolutionary and environmental factors as well as reproductive and dispersal modes on population genetic structure.     

Does lack of intraspecific aggression or absence of nymphs determine acceptance of foreign reproductives in <Emphasis Type="Italic">Macrotermes</Emphasis>?

The rejection or acceptance of a foreign reproductive by an alien colony may not always be as straightforward as cue recognition between worker termites. This paper aims to determine whether adoption of foreign reproductives is caused simply by lack of intraspecific aggression or is contingent on the reproductive status of the host colony. In the fungus-culturing termites, Macrotermes gilvus (Hagen) and Macrotermes carbonarius (Hagen), major workers showed low intraspecific aggression towards non-nestmates irrespective of geographic distance between source colonies. Our results indicated that workers were hardly aggressive towards non-nestmates. In royal cell-swapping experiments, both species responded in a similar way: (1) in host colonies with nymphs present, the foreign reproductives were rejected; while (2) in host colonies without nymphs the foreign reproductives were either accepted and breeding resumed or the host colonies died eventually. Workers from the host colonies preferentially maintained offspring nymphs from which adultoid replacement reproductives develop rather than accepting foreign reproductives. There is no fitness gain for the queenless workers in accepting foreign reproductives; however, there is overall benefit to the newly born population.     

Colony genetic organization and colony fusion in the termite Reticulitermes flavipes as revealed by foraging patterns over time and space

Temporal and spatial analyses are seldom utilized in the study of colony genetic structure, but they are potentially powerful methods which can yield novel insights into the mechanisms underlying variation in breeding systems. Here we present the results of a study which incorporated both of these dimensions in an examination of genetic structure of subterranean termites in the genus Reticulitermes (primarily R. flavipes). Most colonies of this species (70%) were simple families apparently headed by outbred primary reproductives, while most of the remaining (27% of the total) colonies contained low effective numbers of moderately inbred reproductives. Mapping the spatial distribution of colony foraging sites over time revealed that despite the high colony density, the absolute foraging boundaries of most R. flavipes colonies were persistent and exclusive of other conspecific colonies, which suggests that this species is more territorial than has been implied by laboratory studies of intraspecific aggression. Nevertheless, we found a single colony (3% of all colonies) which contained the offspring of more than two unrelated reproductives. Although other studies have also described subterranean termite colonies with a similarly complex genetic composition, we demonstrate here that such colonies can form under natural conditions via the fusion of whole colonies. This study underscores how repeated sampling from individual colonies over time and space can yield information about colony spatial and genetic structure that cannot be obtained from conventional analyses or sampling methods.     

Impact of orphaning on field colonies of Southeast Asian Macrotermes gilvus (Hagen) and M. carbonarius (Hagen) (Termitidae, Macrotermitinae)

Field colonies of Macrotermes gilvus (Hagen) and M. carbonarius (Hagen) were experimentally orphaned to examine their potential for producing replacement reproductives. Orphaned colonies were investigated only once for caste composition at selected time intervals at 3, 6, 9 or 12 months after orphaning. Of the 38 orphaned colonies of M. gilvus, 15 colonies (39.5%) re-established. In M. carbonarius, three colonies out of 20 (15%) re-established. Re-established colonies were headed by adultoids which were morphologically indistinguishable from primary reproductives. In naturally orphaned colonies of M. gilvus, we often found multiple adultoids with normal pigmentation but torn wings, i.e. the colonies retained alates as replacement reproductives. The number of reproductives probably declines over time. It may take alates of M. gilvus 6 months to develop into functional adultoids, and up to 12 months for alates of M. carbonarius. Our results also demonstrate that the presence of sexual castes (nymphs or alates) at the time of orphaning does not necessarily guarantee the success of colonies in re-establishing themselves as breeding colonies. We also found a high prevalence of occupation of the mounds by other termite species, after the death of M. gilvus (18.4%) or M. carbonarius (30.0%) colonies, probably using them as foraging sites.     

Permanent loss of wings in queens of the ant <Emphasis Type="Italic">Odontomachus coquereli</Emphasis> from Madagascar

Winged queens are the most common reproductives in ants. They are morphologically specialized for independent colony foundation, with wings for long-range dispersal and metabolic reserves to raise the first brood. However independent foundation can sometimes be selected against and replaced by fission, featuring short-range dispersal on the ground and reproductives that are dependent on the wingless workers for all non-reproductive tasks. We investigated the evolutionary consequences of this transition on the morphology of the reproductives by collecting 30 colonies of Odontomachus coquereli from Madagascar, the only species in the genus where winged queens have never been found. Data about colony demography, morphometry, allometry and ovarian dissections showed that the winged queen caste has been replaced by a wingless reproductive caste with distinct body proportions relative to the workers or to congeneric winged queens. The 17 reproductives that we measured exhibited little size variability. A single wingless reproductive was found in each colony, corresponding to ‘ergatoids’ in literature. Several facts suggest that colonies reproduce by fission, notably the relatively constant colony size (19±11 workers). The developmental origins of wingless reproductive phenotypes need investigation; little genetic change may be involved, as seen when Odontomachus larvae are parasitized by nematodes. The sole function of wingless reproductives in O. coquereli is reproduction, and they contrast with multi-purpose wingless reproductives found in other ants, where numerous intermorphs occur in each colony and contribute to sterile tasks. Received 15 December 2006; revised 26 February 2007; accepted 1 March 2007.     

Efficient but occasionally imperfect vertical transmission of gut mutualistic protists in a wood‐feeding termite

Although mutualistic associations between animals and microbial symbionts are widespread in nature, the mechanisms that have promoted their evolutionary persistence remain poorly understood. A vertical mode of symbiont transmission (from parents to offspring) is thought to ensure partner fidelity and stabilization, although the efficiency of vertical transmission has rarely been investigated, especially in cases where hosts harbour a diverse microbial community. Here we evaluated vertical transmission rates of cellulolytic gut oxymonad and parabasalid protists in the wood‐feeding termite Reticulitermes grassei. We sequenced amplicons of the 18S rRNA gene of protists from 24 colonies of R. grassei collected in two populations. For each colony, the protist community was characterized from the gut of 14 swarming reproductives and from a pool of 10 worker guts. A total of 98 operational taxonomic units belonging to 13 species‐level taxa were found. The vertical transmission rate was estimated for each protist present in a colony based on its frequency among the reproductives. The results revealed that transmission rates were high, with an average of 0.897 (±0.164) per protist species. Overall, the protist community did not differ between reproductive sexes, suggesting that both the queen and the king could contribute to the gut microbiota of the offspring. A positive relationship between the transmission rate of protists and their prevalence within populations was also detected. However, transmission rates alone do not explain the prevalence of protists. In conclusion, these findings reveal key forces behind a conserved, multispecies mutualism, raising further questions on the roles of horizontal transfer and negative selection in shaping symbiont prevalence.     

Asexual queen succession mediates an accelerated colony life cycle in the termite Silvestritermes minutus

Mixed modes of reproduction, combining sexual processes with thelytokous parthenogenesis, occur in all major clades of social insects. In several species of termites, queens maximize their genetic input into nondispersing replacement queens through parthenogenesis, while maintaining genetically diverse sterile offspring and dispersing reproductives via sexual reproduction. This so‐called asexual queen succession (AQS) has multiple independent origins and its presumed advantages are diverse as well, ranging from multiplication of colony reproductive potential to extension of its lifespan beyond that of the foundress. However, how AQS shapes colony life cycles under natural conditions remains poorly known. The neotropical termite Silvestritermes minutus inhabits small but conspicuous nests, offering a unique opportunity to investigate the impact of AQS on life history. We report on its breeding system, life cycle and sex allocation using social structure census in 137 nests and genotyping of 12 colonies at 12 microsatellite loci. We show that colonies are established by an outbred pair of primary reproductives. In less than 2 years, the foundress is replaced by multiple neotenic queens, arising mostly through automixis with central fusion. Sterile castes, male and most (93%) female dispersers are produced sexually. Colony reproduction is usually restricted to a single dispersal of alates with unbiased sex ratio, taking place after 3 years. We conclude that S. minutus benefits from AQS to maximize colony growth rate and alate production within a very short life cycle rather than to extend colony lifespan. This highlights the versatile role of AQS in different cases of its polyphyletic origin.     

Polymorphism in the neotropical termite Serritermes serrifer

Serritermitidae (Isoptera) is a small and little known Neotropical termite family which includes only two genera: Glossotermes and Serritermes. Despite the lack of detailed studies, it has been assumed that these termites have a true worker caste. A recent study revealed that Glossotermes has a linear development pathway and lacks true workers. Here, we present a study of the polymorphism of Serritermes serrifer Hagen & Bates, a species endemic to the Cerrado ecoregion of central Brazil which lives as an inquiline inside nests of Cornitermes spp. A morphometric analysis was performed based on measurements taken of 11 body parts of 544 specimens of immatures, worker‐like individuals, soldiers, and alates. Sex of specimens was determined by dissection and examination of the seventh sternite. A principal component analysis (PCA) was used to evaluate morphological changes during development. Contrary with previous information from the literature and similar to Glossotermes, Serritermes shows a linear development pathway with two larval instars, two sizes of pseudergates, and a single nymphal morph. Pseudergates apparently undergo stationary molts. Sex ratio among pseudergates is male‐biased, but not as strongly as in Glossotermes. Typical colonies have a single physogastric primary queen and a single primary king. Ergatoid reproductives are relatively rare and some female ergatoids may become strongly physogastric. Nymphoid reproductives were not found. All soldiers are male and bear well‐developed testes.