Mating behaviour of Staminodeus vectoris (Coleoptera: Curculionidae), and the value of systematics in behavioural studies

The mating behaviour of Staminodeus vectoris Franz (Curculionidae: Curculioninae: Derelomini) is described and discussed in light of a phylogeny of Staminodeus Franz. At La Selva, Costa Rica, S. vectoris is associated with the staminodes of the inflorescences of Asplundia uncinata Harling and several other species of Cyclanthaceae. The males have a row of 6–10 teeth along the margin of the protibia, whereas the females have a small, curved spine on the frons. The adults arrive in numbers at the inflorescences during the pistillate phase of the anthesis of A. uncinata, feeding on the staminodes. Eventually, a female detaches a staminode with her mandibles, falls to the ground, and transports it to the site of oviposition in the leaf litter. First, she crawls underneath the staminode, then moves it posteriorly with her legs, and finally returns to its distal end before repeating the process. The female turns on her back and maintains her original position during the movement of the staminode, using her frontal spine as a point of resistance against the substrate. Meanwhile, a male associates with the staminode. The males fight with their prothoracic legs, executing fast blows until their protibial teeth cling and dislodge competitors from the staminode. The positive and negative allometries of the lengths of the male protibia and female spine, are consistent with their functions in the contexts of sexual and natural selection, respectively. The phylogeny of all seven species of Staminodeus hypothesises that female transporting behaviour evolved before male fighting behaviour.     

Mating behaviour in the bees,Dieunomia heteropoda and Nomia tetrazonata,with a review of courtship in Nomiinae (Hymenoptera: Halictidae)

Males of many bees in the subfamily Nomiinae (Halictidae) have numerous secondary sexual characters, which provide much systematic information. Similarly, the use of these structures by males during sexual behaviour may provide useful characters, but the courtship and copulatory behaviour of most of these bees is not known. Structures and behaviour used for courtship and mating are described for two species of nomiine bees, Dieunomia heteropoda and Nomia tetrazonata, along with brief observations of mating in a parasitic bee, Triepeolus verbesinae (Apidae: Nomadinae). A review of mating behaviour within the Nomiinae shows no obvious phyletic patterns, based upon present limited knowledge. The species-specific nature of the male secondary sexual characters suggests they may have evolved in the context of sexual selection, but behavioural data from populations of additional species are needed to evaluate the hypothesis adequately.     

Larval growth rates and sexual differences of resource allocation in the cetoniine scarab Mecynorhina polyphemus Fabricius 1781 (Coleoptera: Scarabaeidae: Goliathini)

Larval ontogeny of the scarab Mecynorhina polyphemus was monitored throughout all instars, and larvae were weighed at 7-day intervals. Durations of the prepupal, pupal and postpupal stages were recorded. Larvae increase their body masses over 300 times during ontogeny. Male imagines are larger than females, and this is primarily a function of faster growth rates during instar III, resulting in significantly heavier larvae at the end of this instar. The durations of the three instars are not significantly different in males and females, but the duration of the prepupal and postpupal phases is significantly longer in males. There is a strong correlation in both sexes between maximal larval mass and the mass of the imago, but larval mass–imago mass scales with significantly different slopes in males and females. Male larvae must allocate increasingly more resources into production of cephalic horns with increments in larval mass, requiring differently proportioned pupal chambers.     

Revision of the Madagascan genus Madecorphnus Paulian (Coleoptera: Scarabaeidae: Orphninae)

A scarab beetle genus, Madecorphnus Paulian, endemic to Madagascar, is revised. Nine new species are described: M. brunneus sp. nov., M. dentatus sp. nov., M. montreuili sp. nov., M. niger sp. nov., M. pauliani sp. nov., M. perinetensis sp. nov., M. peyrierasi sp. nov., M. punctatus sp. nov., M. simplex sp. nov. Diagnosis of the genus is clarified. Distribution map and a diagnostic key to all species are presented.     

Antennation and sexual performance of male digger wasps Sphex ingens Smith (Hymenoptera: Sphecidae)

Antennation can play several roles in hymenopteran copulation, mainly in wasps. The digger wasp Sphex ingens Smith has a very peculiar sexual behaviour, in which forced copulation is a striking element. However, communication through antennation during the pre-copulation and copulation phases and the relationship between the sexual performance of males and the final result of copulation require further clarification. The sexual behaviour of wild populations of S. ingens was filmed during the breeding season in a site between the beaches Meros and Aventureiro, Ilha Grande, southeastern Brazil. We assessed antennation behaviour, courtship duration, sexual performance, and genital clasping. Only successful males had the genital clasping assessed. Evidence found so far points out that the successful males showed better sexual performance – that is, they antennated more in a shorter courtship duration. Also, genital clasping in successful males did not depend on antennation, courtship duration, or sexual performance. Our results shed light on some aspects of the sexual behaviour of wasps, as they explain part of the sexual selection mechanisms adopted by the species.     

Two nesting behaviours and life history of a subsocial African dungrolling beetle,Scarabaeus catenatus (Coleoptera: Scarabaeidae)

Nesting behaviour of a large-sized dung beetle, Scarabaeus catenatus (Gerstaecker), was observed at the Tsavo West National Park, south-eastern Kenya. Although this species is taxonomically a member of a dung-roller group (that is, subfamily Scarabaeinae), it had not only a rolling behaviour but also a tunneller behaviour for nesting. In the former case, the scarab rolled a chunk or a ball of dung some distance (0·5–15·5m) away from the dung pat and buried it under the ground. In the latter case, it dug a tunnel near the dung pat (0–1 m) and transported several pieces of dung into the burrow. In both cases, brood nests were completed by a female alone or by male-female co-operation. Four days after dung burial, the female made one to four brood balls out of buried dung, in each of which she deposited an egg. On the other hand, the male left the nest soon after the female completed oviposition. Even after oviposition, the female stayed in the nest and cared for her progeny until they emerged. This indicates that S. catenatus is subsocial. A major source of offspring mortality was likely to be predation by driver ants (Dorylus sp.). Most females seemed to breed one time in each of two or more successive rainy seasons.     

The puparia of some West African species of Mepachymerus and Steleocerellus (Diptera: Chloropidae)

The puparia of two species of Mepachymerus and three species of Steleocerellus (Diptera: Chloropidae, Chloropinae), reared from wild grasses in West Africa, are described.     

Non-monogamous mating system and evidence of lekking behaviour in the Helmeted Manakin (Aves: Pipridae)

ABSTRACT

Manakins (Pipridae) are a group of Neotropical birds well known for their spectacular lekking displays and non-monogamous mating system. Nevertheless, the two species of Antilophia have been traditionally considered monogamous and, therefore, an exception to this rule. In this paper, we studied the home range and the mating system of a colour-ringed population of the Helmeted Manakin Antilophia galeata in southeastern Brazil. We propose that it is a non-monogamous species that ranges widely during the breeding season, presenting a lekking behaviour in the form of unspectacular but aggressive chasing courtship displays.     

The behaviour of Cotinis nitida Linnaeus,the green June beetle (Coleoptera: Scarabaeidae), on mowed lawns makes them especially vulnerable to bird predators

ABSTRACT

Males of the green June beetle Cotinis nitida are regularly attacked by birds as they search for females on lawns but which bird species feeds on the beetle changes from year to year. In 2018 for the first time on a farm in northern Virginia, brown thrashers (Toxostomum rufum) joined blue jays (Cyanocitta cristata) as major predators of the beetles. The two species employed very different tactics when hunting for June beetles, with the thrashers searching while walking forward on the mowed lawn while the jays scanned for beetles when perched in trees about the lawn. The beetles became very scarce at the lawn in early July in 2017 and 2018 and their predators apparently moved elsewhere. Subsequently, male beetles were occasionally observed patrolling a nearby hayfield in search of mates with rare copulations recorded after July 15. Because predatory birds could not exploit the beetles in the tall grass of the hayfield it seems likely that the mowed lawn constituted an evolutionarily novel ecological trap which made searching beetles conspicuous and easily captured by beetle-hunting birds.     

The occurrence and function of the sphragis in the zerynthiine genera Zerynthia,Allancastria and Bhutanitis (Lepidoptera: Papilionoidea: Papilionidae)

In some butterfly species males attach a large external mating plug termed a sphragis to the female abdomen during mating. This is derived from male accessory secretions and covers the female ostium bursae and surrounding areas, thus preventing or delaying remating. Specimens of all 12 species of the genera Zerynthia, Allancastria and Bhutanitis (Lepidoptera: papilionidae), which form a natural clade within the Zerynthiini, were examined for presence or absence of a sphragis and their male and female genitalia were studied. In all three genera female genitalia lack a typical sinus vaginalis and the sterigma is modified to form an exposed, shiny, well-sclerotized genital plate, derived from the fusion and expansion of the lamellae ante- and postvaginales. The exposed ostium bursae is situated near the posterior end of the genital plate in Zerynthia, whereas in Allancastria and Bhutanitis it is near the anterior end. A crude irregularly formed sphragis was found at least facultatively in all species. The sphragides of Zerynthia and Bhutanitis were generally poorly developed, in most cases only partially covering the female genital plate. In Allancastria the sphragis mostly covered the genital plate entirely, and generally incorporated numerous long scales derived from the male’s 8th abdominal segment; scales were sometimes sparse or absent, probably due to depletion from repeated matings by males. In Zerynthia, males lacked the dense terminal abdominal tuft of elongated scales found in Allancastria, and their sphragis lacked scales. The sphragis of Bhutanitis thaidina incorporated scales from the male valves, whereas in the B. lidderdalii sphragis (and probably B. ludlowi) the scales derived from the male’s 8th abdominal segment. The role of the scales and possible reasons for the difference in the development of the sphragis among these genera are discussed.     

Mating behaviour,territoriality and natural history notes of Phyllomedusa ayeaye Lutz, 1966 (Hylidae: Phyllomedusinae) in south-eastern Brazil

The mating (male courtship, amplexus and oviposition) and male territorial behaviours of Phyllomedusa ayeaye are described from a high-altitude site in the state of Minas Gerais, south-eastern Brazil. Information related to male breeding success and territoriality, as well as egg clutch parameters, is provided, together with qualitative information regarding tadpole phenology and juvenile recruitment. In addition, estimations of sexual dimorphism and numbers of marked individuals are available through capture-mark-recapture sampling. Females bred with males within spatially clustered oviposition sites (broadleaf plants). In some cases, the amplectant couple actively searched for the oviposition site. Males defended territories from other males, employing both acoustic and physical interactions. Some males successfully maintained their calling sites over successive nights, and others seemed to switch among nearby sites during successive nights and tried to disrupt ongoing ovipositions. No significant relationship was found between physical attributes (snout vent length or body mass) of males with breeding success. Also, no influence of the number of nights a male was active in chorus and its breeding success was detected. Therefore, it is proposed that the mating system in P. ayeaye may be opportunistic. Additional information related to reproduction (egg clutch parameters and breeding behaviours) is also discussed for other species of the Phyllomedusa hypochondrialis group and compared with the results of the present study.     

New species and records of the Neoserica (sensu stricto) group (Coleoptera: Scarabaeidae: Sericini)

In this paper we examined newly collected specimens of the Neoserica Brenske, 1894 (sensu stricto) species group housed in Chinese collections. Four new species are described from China: Neoserica (s. str.) mengsongensis Liu & Ahrens, sp. nov. (Yunnan Prov.), Neoserica (s. str.) pseudosangangana Liu & Ahrens, sp. nov. (Guizhou Prov.), Neoserica (s. str.) taibaiensis Liu & Ahrens, sp. nov. (Shaanxi Prov.) and Neoserica (s. str.) yongkangensis Liu & Ahrens, sp. nov. (Zhejiang Prov.). Habitus and the male genitalia are illustrated. Additionally, we provide new distribution records, an updated distribution map and an updated key to the species of the Neoserica (sensu stricto) group.

http://zoobank.org/urn:lsid:zoobank.org:pub:A3C6B300-EAC3-445E-8B14-E1DBB7BBFB7F     

Mating behaviour,nympho-imaginal development and description of a new Mesabolivar species (Araneae: Pholcidae) from the Brazilian dry forest

A new species of Mesabolivar is described from Brazilian forests: Mesabolivar delclaroi. The mating behaviour, postembryonic development, number of egg sacs and eggs, birth rate, number of instars, developmental time until adulthood, sex ratio and size of cephalothorax (per instar) were recorded. The sexual behaviour was described and categorized into four steps: courtship, pre-copulation, copulation and post-copulation. After hatching, individuals presented five instars until maturity. The mean number of eggs (42 ± 16.6) and live births (31.5 ± 3.4) of the first egg sac were significantly greater than that of a second one (23.8 ± 3.8, and 19.25 ± 3.9, respectively). The developmental time from birth to adulthood (130.8 ± 9.6 days) did not differ significantly between egg sacs produced (128.61 ± 11.1). The size of the cephalothorax did not differ among adults or between sexes. The sex ratio revealed a shift in favour of females (4: 3).     

Two new taxa from the Lesser Sundas in the genus Onthophagus (Coleoptera: Scarabaeidae: Scarabaeinae)

Two new Indonesian taxa are proposed in Onthophagus Latreille, 1802, illustrating the composite faunal spectrum of the Lesser Sundas (Indonesia): O. montishannoniae, a new species from Flores, and O. accedens nusatenggaricus, a new subspecies from Lombok and Flores. O. accedens Lansberge, 1883 is, with O. dux Sharp, 1875, placed in what is here defined as the dux subgroup within the subgenus Parascatonomus Paulian, 1932. The three included species‐group taxa are keyed, their status is discussed, and new records are given. The position of O. montishannoniae seems taxonomically and geographically isolated: this species has no known close relatives in the region, neither in the Lesser Sundas, nor anywhere else in Wallacea.     

Asymmetrical male mandibular horns and mating behavior in Agathidium Panzer (Coleoptera: Leiodidae)

Males of some species of Agathidium Panzer have a prominent horn on the dorsal surface of the left mandible. The horn is unique in that it is highly asymmetrical. One species, A. marae Miller and Wheeler, has an additional horn on the right side of the frons. The horns are categorized into four general morphological types. Scaling relationships are investigated for two species, A. angulare Mannerheim and A. pulchrum LeConte. These species exhibit a scaling relationship that is strongly discontinuous (sigmoid) with a prominent “switch point”. Measurement data (pronotal width versus mandible height) are fit to a nonlinear regression model to determine the switch points and slopes at the switch points for the populations of each species. Behaviors associated with mating and other behaviors are described for A. pulchrum. Males use a head‐thrusting behavior to dislodge rival males from the substrate. Horned males appear better able to dislodge opponents. Head thrusting is also used less vigorously on females before and after mating.     

Natural history and behaviour of the primitively eusocial wasp Ropalidia marginata (Hymenoptera: Vespidae): a comparison of the two sexes

We report the natural history and behaviour of the primitively eusocial wasp Ropalidia marginata with a special reference to the males. We found that just as nests of this species are found throughout the year, so are the males. Females spend all their life in their nests but males stay in their natal nests only for 1–12 days and leave to lead a nomadic life. Males maintained in the laboratory can live for up to 140 days. Like all eusocial hymenopteran males, R. marginata males also do not perform any colony maintenance activities. We found that males did not forage or feed larvae. Compared with females, males showed fewer dominance and subordinate behaviours and being solicited behaviour and more feeding self and soliciting behaviours. By comparing males with young females, we found similar differences, except that the males showed similar rates of feeding self and higher rates of subordinate behaviour.     

Deltochilini and Phanaeini dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) in introduced and native ecosystems of Brazil

The dung beetle tribes Deltochilini and Phanaeini (Coleoptera: Scarabaeidae: Scarabaeinae) play an important ecological role in the habitats in which they live. Despite much field work on these beetles in the Neotropical region, biological information on many taxa is still unknown. Here we provide information on species of Deltochilini and Phanaeini including temporal distribution of adults, sex ratio (Male : Female) and measurements of the individuals as well as on ecology and general biology of all species sampled in introduced (pasturelands of Brachiaria spp.) and native (patch of the Brazilian savanna) ecosystems of Brazil. Furthermore, our findings may help to understand the complexity of the effects of mixed ecosystems on the biodiversity of dung beetles.     

Mating behaviour and spermatophore transfer in the shrimp Heptacarpus pictus (Stimpson) (Decapoda: Caridea: Hippolytidae)

Summary

Heptacarpus pictus, a small caridean shrimp inhabiting the low intertidal of southern and Baja California, breeds during the winter, spring, and summer months. Fall is a period of growth. Life span of an individual does not exceed 18 months, with fish predation as the most likely source of mortality.

Females are multiple brooders, carrying developing embryos concomitant with increase in ovary size. Hatching of larvae is followed by a moult, after which the female is attractive to males and receptive to copulation. A distance pheromone does not appear to be involved in attraction of males to females. Males apparently respond to a non-diffusible substance on the exoskeleton of newly moulted females.

Precopulatory behaviour is absent. Copulation can be divided into a series of relatively stereotyped events. Female rejection of the male or his spermatophore is the chief cause of unsuccessful matings.

Males deposit the spermatophore on the underside of the female's first abdominal segment. Sperm packets are formed upon extrusion from the male's genital openings, and are composed of a mucoid material in which sperm are mixed. The glutinous spermatophores adhere to the female's smooth abdominal sternite.

The endopods of pleopods 1 and 2 of the male are different in shape, size and setation from homologous rami of females and juveniles. Endopods of pleopod 1 possess a distally located appendix interna, absent in juveniles and females. An anteriorly projecting process, the appendix masculina, is located on the endopod of pleopod 2 in males. Experiments were performed which showed that these modifications insure proper deposition of spermatophores. Males which had the copulatory rami removed did not transfer spermatophores as successfully as normal males.

Transfer of the spermatophore from the male to the female is a result of the interplay of male pleopods 1 and 2 during copulation. The large expanded abdominal pleurae of females prevent the male's genital opening from contacting her abdominal sternite. Thus, the male's anterior pleopods have become modified to lift the emitted spermatophore from his genital orifices to the first abdominal sternite of the female.