Nest construction and larval behaviour of Onitis belial and Onitis ion (Coleoptera, Scarabaeidae)

Abstract. 1. Female beetles working alone or in cooperation with a male buried dung to make brood masses. O.belial brood masses were packed close together in clusters; each mass was constructed as a horizontal thick-walled tube of dung which was filled with a dung sausage containing two to six eggs. O.ion made vertical sausage-shaped brood masses with one to four eggs.
2. The larvae of both species were able to survive in artificial brood balls as well as in multi-egg brood masses because of their ability to repair larval chambers with their own excrement.
3. The multi-egg brood mass of Onitis has probably evolved from a simple one-egg brood mass. It does not resemble the underground dung mass from which brood balls are made by certain Coprini.     

Nest construction, fighting, and larval behaviour in a geotrupine dung beetle, Ceratophyus hoffmannseggi (Coleoptera: Scarabaeidae)

A pair of beetles worked together to make a series of horizontal brood masses by packing dung into underground chambers. An egg was laid in the soil just beyond the tip of each mass. Resident beetles used their horns to resist intruders of either sex. During head-to-head pushing contests in the nest entrance-tunnel, a stable position was adopted where the horns of each opponent thrust harmlessly against the pronotum of the other. The larva prevented collapse of its chamber by building a rigid tube from accurately positioned faecal pellets. Defects in the larval chamber released no obvious repair behaviour and the larva was, therefore, not able to survive in a free-standing brood ball or in the presence of another larva in the same chamber.
It is a pleasure to thank Sr J. de Ferrer (8 Av. F. Franco, Algeciras) for his help and advice.     

Normal and atypical nesting behaviour of Copris lunaris (L.): comparison with related species (Coleoptera, Scarabaeidae)

Abstract. 1. The lifecycle, mating and larval behaviour of Clunaris are described. Adults appeared in the autumn and nested in the following spring. The female beetle remained in the nest with the brood and could nest again the following year.
2. Nesting was initiated when virgin females were mated in the spring. Brood balls were formed by techniques sirnilar to those used by Scarabaeini. The female beetle left the nest soon after the first imagos broke out of the brood balls.
3. Nesting behaviour was readily modified by external conditions. Many parts of the sequence could be repeated or omitted. The female beetle left the nest if the brood was removed, but she remained for longer than usual if younger brood was substituted near the end of the normal nesting period.
4. Certain experimental conditions released behaviour patterns typical of other species. These were formation of superficial nests or of two-chambered nests, oviposition before completing the brood ball, and coating of the brood balls with soil (all found in other Coprina), as well as ball rolling and ball burial (found in Scarabaeini). The results are discussed in relation to the evolution of Copris nesting behaviour.     

Kleptoparasitic behaviour of Aphodius rufipes (L.) larvae in nests of Geotrupes spiniger Marsh. (Coleoptera, Scarabaeidae)

Abstract.

• 1 Third instar larvae of A.rufipes were found in short vertical shafts in the soil beneath horse dung and they entered the underground brood masses of G.spiniger when these occurred beneath the same deposit of dung.
• 2 A.rufipes larvae excavated shafts (60–80mm deep) beneath dung in cages. Just before diapause they burrowed down to the floor of the cage. Burrowing was inhibited in compact soil and in very dry soil. The feeding larvae were attracted to dung and to moisture and they readily attacked other larvae with their mandibles.
• 3 In cages which contained G. spiniger nests the A.rufipes larvae burrowed down to feed on the G.spiniger brood masses. G.spiniger eggs and larvae did not act as attractants but they were often destroyed if the A.rufipes larvae encountered them by chance.
• 4 In cages which contained G.stercorarxus nests A.fossor larvae burrowed down to feed on the brood masses if no dung was provided at the surface.
• 5 This non-obligatory parasitism arises from the normal behaviour of the larvae and is usually of trivial significance, but under certain conditions the protected environment of an underground nest may favour the survival of the invading larvae.

     

The mesostigmatic mites associated with Copris hispanus (L.) (Coleoptera, Scarabaeidae) in Israel

Works dealing with the association of searabaeid beetles and mesostigmatic mites are shortly reviewed. In the present paper the mite fauna of 106 specimens of Copris hispanus (Scarabaeidae) is investigated. A total of 3732 mites was collected, belonging to 17 species (10 genera, 6 families). The following species are described (or redescribed) and figured: Parasitus coleoptratorum (L.) Berlese, 1906; Parasitus copridis n. sp.; Parasitus hyper-setosus n. sp,; Pachylaelaps hispani Berlese, 1908; Proctolaelaps parascolyti n. sp.; Alliphis halleri (G. & R. Can., 1881); Alliphis gurei n. sp. The degree of specifity of the mite-beetle association is discussed. It is suggested that there is some relation between the social organization of the beetles and the degree of mite infestation, comparable to the mite-hymenoptera association.     

Nesting behaviour of a subsocial African ball-roller Kheper platynotus (Coleoptera, Scarabaeidae)

ABSTRACT. 1. The nesting behaviour of Kheper platynotus (Bates) was observed in the Tsavo West National Park, east Kenya.
2. The construction of the brood ball seemed to be initiated by the female; thereafter, the male joined in. After its construction, the ball was rolled and buried by the male, whilst the female rode on the ball and occasionally helped the male.
3. After burying the ball, the male came out on the ground, leaving the female under-ground. The female coated the ball with soil and her excrement, and let it ferment for about 2 weeks. Thereafter, the female converted the ball into one to four free-standing brood pears, and laid one egg in each pear. The number of pears produced depended on the size of ball. Even after oviposition, the female remained in the nest to care for the brood.
4. Oocytes matured a little before being laid. Excess oocytes were gradually assimilated during brood care.
5. Females seemed most likely to breed in two or more successive rainy seasons.
6. Although male-male aggression was observed, size assortative mating was not observed.     

The repair of larval cells and other larval activities in Geotrupes spiniger Marsham and other species (Coleoptera, Scarabaeidae)

Abstract. 1. G. spiniger larvae repaired openings in their cells by excavating dung from the brood-mass and placing it in the edge of the hole. Thrusting with the head sealed small holes but pushed dung away from larger defects. Sliding and somersaulting movements allowed repair of different parts of a defect. Repair was provoked by contact with the defect, not by changes in humidity.
2. Dung excavated at the anterior end of the cell was transferred by somersaulting, and thrust into the posterior end to seal off foreign bodies. Burrowing by the larvae depended on similar behaviour which moved the whole cell within the brood-mass.
3. Larvae were sensitive to surface contact, making a coordinated attack on a source of stimulation. They also moved towards dung and wet soil.
4. Fluid regurgitated by disturbed larvae killed blowfly larvae when injected, and repelled earthworms.
5. To construct a pupal cell, excavated material was transferred by somersaulting and used to build a transverse partition without the usual vigorous thrusting movements. The ability to re-initiate pupal cell formation was retained for about 4 days.
6. Larvae enclosed in artificial brood-balls enlarged defects while attempting to repair them, but larvae just prior to pupation taken from recently made pupal cells could repair such defects.
7. Aphodius fossor larvae rarely attempted to repair openings in their cells and usually escaped by burrowing (as above), but opening a recent pupal cell always provoked repair.
8. Repair by G. spiniger larvae is closely related to other larval activities but lacks several features that are important for repair by species developing in freestanding brood-balls.     

An analysis of the nesting behaviour of Geotrupes spiniger Marsham (Coleoptera, Scarabaeidae)

Abstract. 1. Female G.spiniger adults working alone made nests each consisting of a vertical shaft leading to a series of horizontal brood chambers filled with dung brood masses. Oviposition near the tip of the brood mass occurred while the egg cell was being completed over the expanded ovipositor. The shaft above each brood mass was filled with soil excavated from the next brood chamber. A similar response also filled artificial diverticula. An avoidance reaction towards buried dung prevented damage to pre-existing brood masses. 2. Virgin females did not make nests and did not avoid buried dung, but after mating (at about 4 weeks after eclosion) both types of behaviour were released within a few hours. 3. The presence of dung was required to initiate but not to maintain nesting behaviour. If dung was removed after oviposition the chamber was filled with soil produced by renewed excavation. Cellulose pulp could substitute for dung in brood mass formation. 4. Beetles interchanged between burrows at different stages before oviposition readily repeated all pre-oviposition behaviour. They appeared to respond to the length of the shaft and of the brood chamber since they extended short shafts and short brood chambers considerably more than those of normal length. After oviposition the beetles continued to make brood masses even under abnormal conditions. 5. Tilting the cage through 90° caused beetles before oviposition to re-orientate their burrowing direction, but tilting just after oviposition caused them to make vertical brood masses. Placing the shaft in a horizontal position towards the end of brood mass formation postponed the termination of this phase. 6. Beetles repeatedly excavated shafts and chambers when transferred to new cages. Conversely they repeatedly made brood masses when maintained in preformed plaster-of-Paris burrows. 7. This nesting behaviour can be described as a reaction chain in which each action generates its own terminating stimulus and initiates the subsequent response. The behaviour before oviposition could be omitted or repeated as required by the environment, but after oviposition there was little response to external interference. These characteristics have direct relevance to the survival of the larvae.     

A virus of black beetle,Heteronychus arator (F.) (Coleoptera: Scarabaeidae)

During a survey for pathogens of black beetle, high mortality was observed in a population in kikuyu pasture at Wharepapa, near Helensville. Several pathogens were isolated from larvae and adults, including a protozoan (possibly Adelina sp.), a rickettsia, a fungus (Beauvaria sp.), a neoaplectanid nematode, and a small RNA virus. The virus was transmitted to larvae of Pseudaletia separata, Galleria mellonella, Aphodius tasmaniae, and Pericoptus truncatus, and a fatal paralysis ensued after 14–37 days. The potential of the neoaplectanid nematode and the virus in control is discussed.     

The evolution of parental behaviour in Scarabaeinae (Coleoptera, Scarabaeidae): an experimental approach

ABSTRACT.

• 1 Dung beetle lifestyles are reviewed. Most Scarabaeinae lay their eggs in dung masses that are packed into underground chambers, but Coprini and Scarabaeini typically lay their eggs in free-standing brood balls and it is in these tribes that parental care of the brood has evolved.
• 2 Brood balls are constructed by aggregating fragments of dung. This technique is derived from the method of gathering dung at the surface. Larvae developing in brood balls are better protected against dehydration and parasite attack. The repair technique of Scarabaeine larvae preadapts them to life in brood balls.
• 3 Parental care by Copris lunaris depends on appropriate responses by the female to the brood, and it has the selective advantage of protecting the brood against parasites. Preadaptations for parental care in‘non-brooding’Coprini are discussed.
• 4 Variations in the basic Copris nesting behaviour are summarized. Similar variations can occur spontaneously in C.lunaris and can also be released by unusual circumstances.
• 5 C.lunaris females could in principle cooperate but certain factors have prevented this social evolution. The significance of the transient cooperation with the male beetle is discussed.

     

Sperm cell number per bundle in Gnorimus nobilis L. (Coleoptera,Scarabaeidae)

An attempt was made to determine the number of spermatozoa per bundle in a scarabaeoid species Gnorimus nobilis both through the analysis of the premeiotic cytology of germ line cells and by counting the spermatids within a spermiocyst at the beginning of the process of spermiogenesis. The obtained results, taken together, indicate that definitive spermatogonia go through a series of 6 synchronous mitotic divisions before entering meiosis as primary spermatocytes, which in turn produce 256 (2⁸) spermatozoa per bundle after completion of meiosis and spermiogenesis. The obtained data are compared with similar ones for other beetle species belonging to the family Scarabaeidae and the suborder Coleoptera-Polyphaga, respectively. Also, some phylogenetic implications of these data are briefly discussed.     

暗黑鳃金龟甲幼虫肠道细菌分离及鉴定

目的从微生态学角度研究暗黑鳃金龟甲幼虫营养生理活动,探讨其肠道菌群的构成,为其资源开发及生物防治提供理论依据。方法按传统分离方法,从暗黑鳃金龟甲幼虫肠道环境中分离纯化获得10个细菌菌株,对其菌体形态、染色反应、培养性状、生理生化反应进行了系统研究。结果研究结果表明,上述10个细菌菌株分别属于鲁氏耶尔森菌（Yersinia．ruckeri）、侧胞芽胞杆菌（Bacilluslaterosporus）、坚强芽胞杆菌（Bacillus．firmus）、放线杆菌属（Actinobacillus）、飞虫杀雄菌（Arsenophonusllasoniae）、不动杆菌属（Acinetobacter）、气单胞菌Aeromonas）、沙门菌属（Sal—moneUa）、短芽胞杆菌（Bacillusbrevis）、变形菌属（Proteus）。结论通过对暗黑鳃金龟甲幼虫肠道细菌的鉴定,其肠道细菌在培养性状、生理性状、生理生化测定等方面存在较多差异。     

Brood ball construction by the non-brooding Coprini Sulcophanaeus carnifex and Dichotomius torulosus (Coleoptera, Scarabaeidae)

ABSTRACT.

• 1 Feeding burrows made by S.carnifex and D.torulosus adults consisted of tunnels filled with sausage-shaped masses of dung. Brood balls were made by taking fragments of dung from an adjacent feeding burrow and aggregating them into a small sphere which was gradually enlarged and then coated with soil.
• 2 S.carnifex adult females showed no response to their own eggs (unlike Copris lunaris: Klemperer, H.G. (1982) Ecological Erltonzology, 7, 155–167). S.carnifex larvae made and maintained an air channel to the upper pole of the ball and they are in this respect preadapted to receive parental care.
• 3 Compared with a brood mass, a brood ball was less likely to be attacked by Meptoparasitic larvae. The soil coat retarded drying of the brood ball by increasing the total mass of moisturecontaining material.

     

Parental behaviour in Copris lunaris (Coleoptera, Scarabaeidae): care and defence of brood balls and nest

Abstract. 1. Nesting female beetles righted brood balls (so as to replace the egg or larva in the uppermost position) and repaired damaged balls. This behaviour required the presence of an egg or larva in the ball, or of a short-lasting material found just after oviposition. The shape of the ball was also a righting stimulus since artificial ellipsoids were stood on end.
2. Balls containing dichloromethane extracts of C.lunaris brood were righted and repaired. Eggs and larvae of several other Scarabaeidae did not release these responses but were destroyed.
3. Righting behaviour was released when brood was absent from the top of the ball. The beetle then crawled vertically downwards and, if it encountered the displaced apex, a novel rolling action followed which automatically turned the ball towards the correct position.
4. An opening made in the nest was repaired with soil excavated from the chamber floor. Clunaris adults and Aphodius fossor larvae were attacked if they were encountered in the nest.     

White grubs,Holotrichia rustica and Holotrichia mucida (Coleoptera: Scarabaeidae) as pests of teak (Tectona grandis L. f.) seedlings

Abstract Field observations were carried out between 2002 and 2005 on bio‐ecology of white grubs infesting teak (Tectona grandis Linn. f.) seedlings at Ramdongari Forest Nursery, Forest Development Corporation of Maharashtra, Nagpur in central India. The study collected the data required for an integrated pest management strategy against the white grubs. The species damaging teak seedlings were Holotrichia rustica (Burmeister) and H. mucida Gyllenhal. The beetles (adults) of both these species began to emerge just after the pre‐monsoon showers and when the relative humidity had risen rapidly over several days, but before the first monsoon rains. While the adults fed and mated on naturally growing bushes of Ziziphus jujuba, Z. mauritiana, Z. xylopyra, Acacia leucophloea and A. catechu immediately after the emergence from the teak beds in the nursery, the immature stages (grubs) of both species fed on roots of the teak seedling, leading to plant death. This is the first report of (i) damage caused to teak seedlings by grubs of H. rustica and H. mucida, and (ii) of Z. jujuba and Z. mauritiana being hosts for the beetles of H. mucida and H. rustica. It is also the first detailed report on the field bio‐ecology of the H. rustica and H. mucida as major pests of teak. White grubs are among the toughest‐to‐manage pests of economic importance and information presented here on the pest incidence and damage of H. rustica and H. mucida is important to researchers and nursery field managers for the management of these pests on teak.