Landcare Research - Manaaki Whenua

Landcare-Research -Manaaki Whenua

FNZ 69 - Carabidae (Insecta: Coleoptera): synopsis of species - Popular summary

Larochelle, A; Larivière, M-C 2013. Carabidae (Insecta: Coleoptera): synopsis of species, Cicindelinae to Trechinae (in part). Fauna of New Zealand 69, 193 pages.
( ISSN 0111-5383 (print), ISSN 1179-7193 (online) ; no. 69. ISBN 978-0-478-34738-8 (print) , ISBN 978-0-478-34739-5 (online) ). Published 7 Mar 2013
ZooBank: http://zoobank.org/References/E5F2CF9A-BC6D-47C1-A3EC-A948CB58ECC7

Popular summary

Ground-beetles

The family Carabidae (ground-beetles, including tiger beetles) is composed of over 34,000 species distributed among 1,927 genera worldwide. Carabids occupy most land habitats on nearly all continents. These beetles are abundant in the field and attract attention with their peculiar shape and coloration. They are mostly active at night and prey on a wide range of small animals such as other insects and spiders; some species are active during the day and feed on plant tissue. Most ground-beetles, in temperate climates at least, live at the surface of the ground, while some species dwell in the soil (e.g., Anillina), in caves (e.g., Trechini, Harpalini), or on the vegetation (e.g., Zolini, Lebiini). Most New Zealand species cannot fly, which reduces their dispersal capacity and affects the flow of genes defining their body shape, making it rather variable. In 2001, Larochelle & Larivière’s Catalogue (Fauna of New Zealand 43) recorded 5 subfamilies, 20 tribes, 78 genera, and 424 species for this country, whereas this new work recognises 7 subfamilies, 20 tribes, 97 genera, and 518 species. When completely inventoried and described the fauna will likely reach 800 species. Compared with larger or warmer regions of the world, the New Zealand fauna may appear relatively small, but New Zealand is a very special place – a biodiversity ‘hot-spot’ – with over fifty genera (about 60 % of fauna) found nowhere else in the world. The remaining genera not endemic to this country are made up of overseas genera introduced mainly from Australia and native genera shared with Australia and other parts of the world.

In New Zealand, ground-beetles are generally recognised by the following body features: length, 1.0–39.0 mm; colour dark (usually black or brown); elytra (wing covers) rarely spotted; dorsal surface without hair cover; head narrower than pronotum (dorsal part between head and wings); mandibles well developed, with sharp tips; eyes moderate in size; antennae thread-like or beaded like a necklace, composed of 11 segments; pronotum narrower than elytra, with a pronounced mobility; legs long and slender, fit for running; tarsi (last part of legs) composed of 5 segments; elytra fused, with striae (deepened lines) present; membranous wings very short, almost absent. Most carabids are recognisable alive by a peculiar way of running on the ground.

As a family, Carabidae are sensitive to their environment and are commonly used as biological indicators to evaluate the diversity of life in ecological systems, indicate the influence of landscape changes, evaluate environmental health, predict the effect of climate changes, select habitats for nature conservation, and characterise forest soil. They can also be used to control pest insects (e.g., caterpillars). In the future, ground-beetles may become more commonly used in biological control, e.g., as natural control agents against harmful insects, especially soil pests, or as control agents of weeds, especially their seeds. In New Zealand, conservation biologists have listed many, often large-sized carabids, as rare or threatened and worthy of protection.

This Fauna of New Zealand contribution is aimed at specialists and non-specialists; it should greatly facilitate identification and information gathering. Its purpose is to provide an overview of 134 species and subspecies belonging to the tribes Cicindelini, Pamborini, Amarotypini, Migadopini, Clivinini, Moriomorphini, and Trechini. This work is one more step in the authors’ goal of reaching an overall understanding of the New Zealand carabid fauna within a reasonable time frame and making relatively large amounts of information available for practical use by a wide range of end-users.

Cicindelini. Tiger beetles are represented by two endemic genera and 16 species occurring on the North, South and Stewart Islands. New Zealand species are mostly active during the day and live in a range of habitats such as coastal sand beaches and dunes, riverbanks, grasslands, and roadsides. These stunning insects are recognised by the metallic colour of their body, hairy legs, very large eyes, strongly toothed mandibles, and pale markings on the elytra. Adults and larvae are voracious predators, often feeding on ants. The larva lives in a deep burrow dug into the soil, placing itself at the burrow’s entrance, attached to the wall by two pairs of hooks on the abdomen, and awaiting organisms on which it preys.

Pamborini. This tribe is represented by the endemic Fairburn’s snail-eater (Maoripamborus fairburni) occurring only in the northern part of the North Island. This beetle is active at night, living in forests under logs and fallen branches. It is a fascinating flightless insect recognised by its elongate head with mouthparts adapted to feed on snails.

Amarotypini. This tribe occurs only in New Zealand and is known from a single endemic genus and species (Amarotypus edwardsii) found on the North, South and Stewart Islands. This flightless beetle is easily recognised by its metallic bronze colour and its oval shape. It is active at night, hiding during the day under the bark of live southern beech trees. When disturbed, the beetle drops to the ground or emits a strong smell.

Migadopini. These insects, also known as Austral shiny carab beetles, occur in New Zealand, Australia, the Falkland Islands, and southern South America. The New Zealand fauna comprises three endemic genera and 18 species. Some species occur only on subantarctic islands (Antipodes, Aucklands), while most species are distributed on the South and Stewart Islands. These beetles often live along the edges of rills and seepages running through forests or in high altitude meadows and fellfields. They live in groups and are active at night, often hiding during the day under stones. They are also flightless and predatory.

Clivinini. This tribe occurs throughout the world. The New Zealand fauna is known from a single genus (Clivina) and four species introduced from Australia, occurring on the North and South Islands. Slope-rumped beetles are recognisable by their narrow-waisted body, forelegs with finger-like elongations, and strongly developed mandibles. They live in groups and are active at night, living in wet or moist areas, hiding in burrows during the day, and flying readily to lights at night.

Rhysodini. Four genera and six endemic species of Wrinkled bark beetles are known from New Zealand. They are darkly coloured, have cylindrical, narrow-waisted bodies and bead-like antennae. Of the six New Zealand species, five are found only in the northern part of the North Island; the sixth species extends its range to northern areas of the South Island. These beetles can be found in fallen logs, standing dead trees, stumps, woody roots, and under loose bark. They have been observed feeding on slime moulds or fungi.

Moriomorphini. This tribe occurs in the Australian Region, on Pacific Islands, and in southern South America. The New Zealand fauna is composed of seven genera and 48 species distributed on the North and South Islands; they are endemic except for a single species introduced from the Australian region. These insects are mostly flightless, active at night, and probably predatory. They inhabit forests, fields, sand dunes, and the vicinity of streams. They are often found during the day in leaf-litter or under logs, fallen branches, and stones. Several species occasionally climb on trees. Many species have strongly convex and ovate elytra (wing-covers), giving them a “hump-backed” appearance. The largest genus (Trichopsida) is known from 18 species occurring in southern areas of the North Island and on the South Island. This genus is unique in having palpi (structures fit to touch) with hairy last segments. Many species have strongly reduced eyes, swollen tempora (temples), pale and flattened body, and long hair-cover, suggesting subterranean habits. Some species can be collected only by using soil-washing techniques.

Trechini. This tribe is represented by 11 genera and 34 flightless species distributed from the North Island to the subantarctic islands. All representatives of this group are endemic to New Zealand, except for one species also occurring on the Falkland Islands, South Georgia Island, and in Patagonia. Most species are cave-dwellers, many live on the banks of streams, and some occur in the vicinity of seashores, e.g., under stones and among gravel. A single species is found in the humus and leaf-litter of southern beech rainforests. Cave-dwelling species are usually pale in colour, flat-bodied, without eyes, and with long antennae and legs. Species of this tribe are probably predacious. The most diverse genus is Duvaliomimus with 13 species and two subspecies; they live in groups and are active at night, hiding during the day under stones and among gravel.