Tve356 Oberprieler.Qxp

1 2 ROLF G. OBERPRIELER & ERIK ARNDT 1CSIRO Entomology, Canberra, Australia, 2University of Applied Sciences, Bernburg, Germany ON THE BIOLOGY OF MANTICORA FABRICIUS (COLEOPTERA: CARABIDAE: CICINDELINAE), WITH A DESCRIPTION OF THE LARVA AND TAXONOMIC NOTES Oberprieler, R.G. & E. Arndt, 2000. On the biology of Manticora Fabricius (Coleoptera: Cara- bidae: Cicindelinae), with a description of the larvae and taxonomic notes. – Tijdschrift voor Entomologie 143: 71-89, figs. 1-24. [ 0040-7496]. Published 5 July 2000. Observations from both the field and captivity on the biology and behaviour of Manticora in southern Africa gathered over two decades are collated and presented under the aspects of activity patterns, locomotion, escape and defence, hunting, prey detection, prey capture and feeding, fighting, mating and mate-guarding, oviposition, sheltering and hibernation, and prey spectrum for the adult beetles, and activity patterns, tunnel construction, prey detection, prey capture and feeding, and prey spectrum for the larvae. A likely parasitoid of the larva is identified. The larvae and aspects of the hunting behaviour of adults and larvae are illustrated in colour for the first time. Contrary to earlier reports, the adults hunt their prey by smell and are opportunistic diur- nal predators of phytophagous terrestrial insects, not ‘snail-shell breakers’ specialized to prey on strongly sclerotized beetles. The large, sexually dimorphic mandibles fulfil an additional role dur- ing mating in that they enable the male to ride on the female in a prolonged mandibular am- plexus and guard her against other males. The asymmetrical development of the male mandibles appears to represent an evolutionary compromise between the selection pressures of prey capture and mate guarding. The larvae of the three common species of the genus, M. tuberculata de Geer, M. mygaloides Thomson and M. latipennis Waterhouse, are described in all instars. They are characterized by eight autapomorphic character states and also display some characteristics shared with the Megacephala group, supporting the notion of a common early split from the re- maining cicindelines. It is concluded that the current classification recognizing several closely similar and largely sympatric species is untenable from a biological and evolutionary perspective and that, in addition to the above-mentioned species, only M. congoensis Péringuey and M. gru- ti Boucard appear to represent natural but allopatric species. A thorough and comprehensive sys- tematic revision of the genus is required to fully clarify its taxonomy. Correspondence: R. Oberprieler, Division of Entomology, CSIRO, G.P.O. Box 1700, Canber- ra, ACT 2601, Australia. E-mail: [email protected] Keywords. – Cicindelinae; Manticora; biology; behaviour; larvae; systematics; southern Africa. Despite the interest that the large southern African ratory in southern Africa over a period of twenty tiger beetles of the genus Manticora have generated years. This paper collates all the behavioural observa- for more than a century among students and collec- tions of Manticora obtained from mainly three popu- tors of tiger beetles, little is known about their biolo- lations representing (according to the current state of gy and ecology. Yet, in view of the basal phylogenetic taxonomy of the genus) two species. Descriptions of position of the genus (Arndt & Putchkov 1997), all three larval instars of the genus are provided, based knowledge of its larva and larval habits is crucial to on specimens from these and some other recently understanding its relationships to other cicindeline sampled populations. Finally, the function of the en- genera. Unfortunately also, much of the scanty bio- larged mandibles in the males and the bearing of dif- logical information that has been published on these ferences in characters of the larvae and of behavioural beetles is unsubstantiated or incorrect, as shown by traits on the taxonomy and species boundaries in the the senior author’s observations in the field and labo- genus are discussed. 71 Downloaded from Brill.com10/04/2021 08:06:47AM via free access T E, 143, 2000 Sketchy early biological notes on Manticora were as one of the few totally nocturnal cicindeline genera, published by Castelnau (1863), Lucas (1883) and Si- but at least did not perpetuate the ‘snail-shell breaker’ mon (1894). Péringuey (1893) provided a more de- myth. Rather, his summary of the mandibular am- tailed account of the habits of adult Manticora, his plexus and contact-guarding of females by male tiger observations and interpretations being, in compari- beetles implicitly applies to Manticora as well and is in son with those of later authors, remarkably acute and agreement with both Péringuey’s (1893) early obser- accurate, if somewhat anthropomorphic (‘ … perched vations and with our own conclusions regarding the high on their legs [they] move about in the dry barren function of the apparently allometrically developed plains of the Karoo, in a jerky impetuous manner, mandibles of the males (see below). which implies a bold, fearless temper, evidently aware Oberprieler & Grobbelaar (1991) published a pre- of its physical power.’, p. 3). Although Péringuey liminary, popular version of the observations on M. could not ascertain the precise identity of the natural latipennis Waterhouse, detailed below, sketching the prey species of these beetles, he judiciously suspected general life history and behaviour of the genus. Wern- that a common grasshopper and termites served as the er & Wiesner (1995) added a (correct) observation on principal food of the adults and larvae, respectively. the daily activity period of M. mygaloides (‘damaren- He also noticed the sexual dimorphism of the sis’) and a vague one as ‘hunting for myrmopods and mandibles and recognized that their greater develop- [the tenebrionid] Psammodes vialis’. ment in the male ‘has probably been acquired for the The first (but superficial) description of a larva of purpose of seizing hold, as they do, of the broad neck Manticora was given by Kolbe (1885), based on a spec- of the female for mating’. Perhaps most significantly, imen from the ‘Mission Barmen in Afr. merid. occid.’ he realized that the great variability in size and devel- (evidently the present Gross-Barmen near Okahandja opment of characters in these wingless beetles is large- in Namibia, 22.05S 16.44E) assignable to M. myga- ly due to their limited vagility and consequent isola- loides Thomson (see taxonomic notes below). Shortly tion of populations, as well as to greatly varying climatic afterwards, Péringuey (1893) described the larva of M. conditions and availability of food in their generally tuberculata de Geer from Vanwyksvlei in the Cape drought-prone habitats. Province of South Africa (30.21S 21.49E). Horn Later authors were less astute and careful in their (1915) illustrated a larva of M. tuberculata tibialis Bo- observations and interpretations of the habits of Man- heman but gave no proper description nor details of its ticora. Poulton & Marshall (1902) compared it with origin (but see Material examined). Much later, Leffler the similar-sized and -coloured genus Anthia (Cara- (1980) described a defective larva of M. latipennis from bidae) and argued that it has ‘a similar warning atti- Beira in Mozambique (19.50S 34.55E), but some of tude … but it cannot project its protective secretion, the characters he described are evidently incorrect (see which merely exudes when it is handled; the liquid below). Putchkov & Arndt (1994) included Manticora also is not acid as in Anthia, but possesses a strong in their key to all known tiger beetle larvae and illus- smell.’ – a complete fabrication since Manticora does trated several important characters. not exude any noticeable defensive secretion. Thiele (1977) portrayed Manticora as representing an ex- MATERIAL AND METHODS treme case of ‘procerization’, as typical in snail-shell breaking carabids, and suggested the large develop- Populations studied ment of its mandibles to be an adaptation to particu- The observations reported here were undertaken larly large and resistant prey such as scorpions – in to- over a period of twenty years both in the field in the tal ignorance of the evident sexual dimorphism of natural habitats of these beetles as well as in captivity these structures. Roer (1984), who published the most in Pretoria, South Africa. Adult beetles and larvae comprehensive study of Manticora behaviour to date, from several populations were kept in captivity al- refuted Thiele’s hypothesis that these beetles are spe- most continuously from 1984 to 1996. Detailed ob- cialized scorpion predators in a laboratory experiment. servations and experiments were carried out from one However, he espoused the ‘snail-shell breaker con- population in the Northern Cape Province and two cept’, applying it instead to strongly sclerotized prey in the former Transvaal Province (currently Northern such as apterous, terrestrial tenebrionid beetles (even Province and Gauteng) of South Africa, with addi- though his own experiments demonstrated that Man- tional observations from populations in northern and ticora cannot crush sclerotized Onymacris species). central Namibia and the Northern Cape Province Further, he alleged that Manticora is essentially a noc- and the Northern Province of South Africa. turnal hunter that tracks its prey visually – apart from Our first observations were by the senior author on being almost contradictory, both

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