Ensifera

The Ensifera consists of about 10,000 species in 10 families. The phylogeny of Ensifera has been most recently investigated by Gwynne (1995) and Desutter-Grandcolas (2003). Among ensiferans are some clear relicts, such as members of the Stenopelmatoidea and Hagloidea. As alluded to earlier, Ensifera is the older of the two suborders, with putative members recorded from the very end of the Permian (Bethoux et al., 2002), and the lineage was certainly established during the Triassic. Numerous ensiferan families are represented in the Mesozoic (Figures 7.29 to 7.32), and even putative gryllids are documented from the Triassic along with the presently relict haglids. Tettigoniidae are documented from as long ago as the Early Cretaceous. Other modern families such as Stenopelmatidae (Gryllacridinae) and Gryllotalpidae are known from the Early Tertiary. Among the various extinct lineages of Ensifera, perhaps the most distinctive are the Phasmomimidae from the Late Jurassic. Phas-momimids had long wings and may have been related to the Haglidae.

The superfamily Stenopelmatoidea consists of four cricket-like families (Stenopelmatidae, Rhaphidophoridae, Schizodactylidae, Anostostomatidae), principally occurring

Schizodactylidae

7.29. One of the last occurrences of Elcanidae is in 120 myo limestone from the Cretaceous of Brazil. Elcanidae were diverse and abundant from the Late Triassic to the mid-Cretaceous, having gone extinct presumably during the Late Cretaceous. Although they had long, ensiferan-like antennae, they were probably more closely related to grasshoppers and locusts. AMNH; body length 14 mm.

7.29. One of the last occurrences of Elcanidae is in 120 myo limestone from the Cretaceous of Brazil. Elcanidae were diverse and abundant from the Late Triassic to the mid-Cretaceous, having gone extinct presumably during the Late Cretaceous. Although they had long, ensiferan-like antennae, they were probably more closely related to grasshoppers and locusts. AMNH; body length 14 mm.

7.30. Cricket (Gryllidae) from the Early Cretaceous of Brazil. The earliest crickets occur in the Late Triassic; by the time of the Santana Formation in Brazil 120 mya, they were diverse and abundant. AMNH; body length 19 mm.

in New Zealand and Australia. Some stenopelmatoids have an imposing habitus and include the Jerusalem crickets, wetas, cave crickets, and king crickets. Most species are flightless and nocturnal, scavenging for arthropod remains, but they can be omnivorous or even predatory. The former family Gryllacrididae is now considered a subfamily of the Stenopelmatidae, as are the Schizodactylidae in some classifications (e.g., Gorochov, 2001). Gryllacridids are best known for the raphidophorines, the so-called camel crickets, which are named for the short, hump-back body but which also have extremely long antennae that they constantly wave back and forth. The large genus Ceuthophilus contains hundreds of species, which are common inhabitants of caves, basements, and rocky areas.

Tettigonioidea consists of the familiar katydids and bush crickets and, with about 6,000 species, is the most diverse lineage of Ensifera. Presently, the superfamily consists of only the nominate family and several subfamilies that are some times given family rank. Tettigoniids are large insects occurring throughout the world. While many are of little economic importance, just as many species can cause extensive damage to crops and reach pest levels, a few even swarm similar to locusts. Perhaps the most widely known of such pests is the Mormon cricket, Anabrus simplex. Many tettigoniids are arboreal or live in bushes (hence the name bush crickets) and are remarkably cryptic, typically mimicking leaves (Figure 7.26), but also mimicking lichens (Figures 7.24, 7.27) and mosses (Figure 7.25).

The superfamily Hagloidea contains a single modern family with two subfamilies that seem to intermingle traits of the Tettigonioidea and Grylloidea. Hagloids were much more diverse in the past, extending at least into the Triassic, apparently diminishing in diversity through the Cretaceous.

Grylloidea contains the familiar crickets (Gryllidae) as well as the mole crickets (Gryllotalpidae) and ant crickets (Myrmecophilidae). Each of these families have a worldwide distribution, but only the gryllids are of any significant diversity. Gryllotalpids and myrmeophilids together amount to

7.31. Another cricket from the Cretaceous of Brazil. AMNH; body length 21 mm.
7.32. An ensiferan with a long, thin ovipositor from the Early Cretaceous of Brazil. AMNH; length 42 mm.

slightly more than 100 species, while Gryllidae accounts for about 570 species. Crickets are the most famous of all ensifer-ans, particularly for their songs. While crickets are familiar to everyone, the other grylloid families are a bit more unusual. Mole crickets have remarkably molelike fossorial forelegs (Figure 1.26), modified for digging their way through soil and sand in a system of tunnels just like moles. These forelegs are also used for excavating the roots of various plants on which individuals feed. Myrmecophilids are small, apterous, scale-covered inquilines of ants, a few of which are associated with termites.

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