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Home , Altica chalybea, Anomoea, Babia (beetle), Baliosus, Bassareus (beetle), Blepharida

Conservation of Biological Diversity: A Key to the Restoration of the Chesapeake Bay Ecosystem and Beyond. G. D. Theires, editor. Maryland Department of Natural Resources, Annapolis, MD, 1998

THE LEAF (INSECTA: COLEOPTERA: CHRYSOMELIDAE): POTENTIAL INDICATOR ASSEMBLAGES FOR NATURAL AREA MONITORING

C. L. Staines and S. L. Staines 3302 Decker Place, Edgewater, MD 21037

Abstract: Chrysomelids are model herbivores. Most species are monophagous or narrowly oligo- phagous on a small number of plant families. In the tropics, the area most studied, chrysomelids have been found to be an excellent indicator of local species richness, due to not only their relative abundance but the ease of morphospecies sorting by a nonspecialist. The diversity of chrysomelids is exceptionally rich and a function of local plant diversity. These factors make chrysomelids an excellent candidate for indicator species assemblages for natural area monitoring. A project was started in 1997 on Plummers Island, Maryland, to determine whether chrysomelid species assemblages are indicators of plant diversity, site disturbance, and environmental heterogeneity. At this site we have the advantage of historical collection data dating back to 1901 that can be used as baseline information. . : - ' , •

INTRODUCTION .. the major shapers of ecosystems. Many think that represent approximately 90% of all ecosystems such as the African savannah are shaped by species including plants (Pimentel et al. 1992), with vertebrates, but without the coprophagous arthropods the accounting for approximately 80% of all system would soo'n be overwhelmed with accumulated species diversity (Samways 1992). Together with micro- dung. Our dependence on invertebrates for survival is organisms, insects make up most animal biomass and mostly ignored (Wilson 1987). show the greatest diversity of ecological roles (Coulson Arthropods are found in every conceivable habitat and Crossley 1987). They are also known to be especial- and have many different functions important in ly vulnerable to small-scale habitat destruction (Ehrlich sustaining the balance of ecosystem processes (Wilson and Murphy 1987; Murphy et al. 1990). 1987; Hawkins and MacMahona1989; Walker 1992). American culture views arthropods as pests that need Insects are highly specialized in their niche require- to be controlled or eradicated (Byrne et al. 1984; ments, with diverse ecological roles that provide Howarth and Ramsay 1991; Kim 1993). The public's low important services to the ecosystem processes, as decom- esteem of invertebrates and fear of "creepy crawlies" is posers, consumers, predators, and parasites (Swift and exploited by the advertising industry's message that the Anderson 1989; Morris et al. 1991; Miller 1993). The only good bug is a dead bug. The only exceptions are active decomposition of plant and animal matters by aesthetically accepted species (e.g., butterflies) and those , termites, and beetles is essential to material- perceived as economically beneficial (e.g., honey bees). recycling systems (Frost 1959). Predators play an This negative perception and disproportionate amount of important role in regulating populations of phytophagous attention extends to conservationists (Pyle 1976; Mc- pests (DeBach and Rosen 1991; Olembo 1991). Arthro- Naughton 1989; Hafernik 1992). pods and other invertebrates are the major movers and It is a common misconception that vertebrates are shakers in subterranean ecosystems including litter

233 layers. They are involved in every aspect of the eco- feeding, and mating may all occur on one or a few neigh- system processes (Kiihnelt 1976; Paoletti et al. 1991). boring plants. Even in infertile or impoverished habitats, arthropods support the ecosystem in which insectivorous vertebrates INDICATOR SPECIES ASSEMBLAGES flourish (Braithwaite et al. 1988; Braithwaite 1991). The value of invertebrates as environmental indi- Within insects, beetles (Coleoptera) is the largest cators is only beginning to be appreciated (Magurran order, with more than 290,000 described species (Wilson 1988; Pearson and Cassola 1992; Oliver and Beattie 1987). Beetles are divided into 134 families, 114 of 1993). Indicator species are used to assess environ- which occur in America north of Mexico, they are found mental effects of human activities, determine regional living in just about every habitat except the open ocean, patterns of , measure changes in community and they may occupy any trophic level (Downie and structure and function, and estimate land value (Hutto et Arnett 1996). al. 1987; Murphy et al. 1990; Noss 1990; Pearson and Chrysomelidae (leaf beetles) is one of the largest Cassola 1992). Insects show great potential as environ- families of beetles with approximately 50,000 described mental indicators because they are often specialized, they species worldwide placed in 19 subfamilies (Lopatin are easily observed and monitored in the field, and their 1977). This makes the family second only to the needs are often correlated with the needs of other fauna Curculionidae (weevils, Insecta: Coleoptera), and it has and flora (Wilson and Peter 1988; Samways 1989). more than twice the species richness of birds and Much of the previous work involving indicators has mammals combined (Klausnitzer 1981). In North used one or a few species. The weakness of this America, there are 1,481 species in 188 genera (Arnett approach is its narrow focus, which may result in the 1985). The chrysomelid fauna of Maryland has not been protection of one organism at the expense of others documented. Cavey and Staines (unpublished data) list (Landres et al. 1988; Kreman 1992, 1994; Kreman et al. 373 chrysomelid species in Maryland. 1993). Recently the concept of inventorying taxonomic Most chrysomelids live on terrestrial, aquatic, or assemblages that are likely to represent environmental subaquatic plant material as both larvae and adults as patterns, distributional patterns of species in other root, leaf, flower, or pollen feeders, whereas stem boring, unrelated assemblages, or the overall biodiversity of an leaf-mining, detritus-feeding, and ant-nest associates are area has been proposed (Kreman 1992,1994; Kreman et found among relatively few species. al. 1993; Pearson 1994; Favila and Halffter 1997). Chrysomelids are usually thought of as plant pests, A good indicator species assemblage should have both through direct plant feeding and through trans- several characteristics of which the most important are as mission of plant viruses (Selman 1988). Metcalf (1986) follows: (1) The indicator assemblage should be from a reported that the Diabrotica costs U.S. farmers $1 speciose taxon. The taxon should be important in the billion annually in corn alone. However, other chrysom- structure and function of the target ecosystem. (2) There elids perform useful roles in biological control of weeds must be sufficient information available on the (White 1996), with the number of those being evaluated and natural history of the indicator assemblage to allow for such services increasing throughout the world. for the identification of species and the ecological Chrysomelids are also the target of biochemical pros- interpretation of the results. (3) The higher taxa should pecting. Many species sequester or modify plant be broadly distributed geographically and occupy a chemicals whereas others apparently manufacture a breadth of habitats. (4) The indicator assemblage must unique chemistry against predators (Pasteels et al. 1988, be easy to capture and the capture method must be 1994). Some of these compounds may be useful to standardized. An asymptote should be reached in several humans. weeks or months. (5) The indicator assemblage must be The Chrysomelidae are model herbivores. The one for which collection and other necessary activities majority of species are monophagous or narrowly can be carried out without jeopardizing the conservation oligophagous on a small number of plant families. of any member of the assemblage. (6) Capture data must Association with the host plant is intimate and pro- provide enough information to determine the com- longed. Oviposition, larval feeding, pupation, adult position and structure of the assemblage and its inter-

234 action with the rest of the community. Chrysomelids with ant nests and feed on ant eggs, exuviae, dead ant have not yet been evaluated as an indicator species bodies, and other refuse. Adults feed indiscriminately on assemblage but with a properly designed protocol the flowers, buds, young leaves, and pollen. Females either family meets all of these characteristics. drop their eggs to the ground or glue them to leaves. Eggs resemble seeds and are carried by ants to their Speciose Taxon nests. Not all clytrine larvae live in ant nests, but larvae There are approximately 50,000 chrysomelid species of species in some genera live under stones in the vicinity worldwide (Lopatin 1977), making the family the second of ant nests (Jolivet and Hawkeswood 1995). largest in the animal kingdom. It has more than twice - Larvae of the 2,300 described the species richness of birds and mammals combined worldwide Cryptocephalinae species are free-living case (Klausnitzerl981). bearers and are either phytophagous or detriticolus. Adults are phytophagous on a wide range of plant Natural History families (Jolivet and Hawkeswood 1995). As with most large groups, the Chrysomelidae is Chlamisinae - The larvae of this subfamily are free- very diverse biologically. The family is divided into 19 living phytophagous case bearers. Adults and larvae of subfamilies (Seeno and Wilcox 1982). The following is the 360 known species are extremely cryptic. The larval a summary of the biology of the 14 subfamilies known to case resembles a caterpillar or excreta of a large . occur in Maryland. Although possessing functional wings, adults seldom . - The 150 worldwide Donaciinae species Adults are also protected by their hard integument and are aquatic or subaquatic with adults and larvae feeding ability to retract the head into the pronotum and legs into on emergent vegetation. Larvae feed in the stems or ventral grooves. Retraction of these body parts makes the roots of plants and extract oxygen from their host plant chlamisine appear like caterpillar droppings (Jolivet and (Jolivet and Hawkeswood 1995). It appears that the Hawkeswood 1995). There are two scientifically tested genus prefers running water habitats, whereas definitive methods of distinguishing between the chlami- Plateiimaris prefers quiet or swampy water. sine and caterpillar droppings:- If it does not smear in Orsodacniinae - The biology of the 11 species of your hand or dissolve in alcohol it is a chlamisine. Orsodacniinae is not well known. Adults are common on - The Eumolpinae is a large group of flowers in the spring, and the larvae are thought to be about 3,500 known species worldwide. Most species are leafminers on various plants in the Rosaceae (Jolivet and compact and many have metallic coloration. Adults lay Hawkeswood 1995). their eggs in soil crevices. Larvae are root feeders, often Zeugophorinae - This is a small group of 51 known feeding in groups in earthen cells 5-10 cm (2-4 in.) species worldwide. Larvae mine the young leaves of below soil level. Most species studied are polyphagous. various Salicaceae, Juglandaceae, Corylaceae, and Betu- Adults may feed on the larval host plant or a wide variety laceae (Jolivet and Hawkeswood 1995). of plants (Jolivet and Hawkeswood 1995). Criocerinae - The Criocerinae, with about 1,400 - The 3,000 known Chrysomelinae described species worldwide, is a difficult group to species are very host specific at the generic and species generalize. Most North American species feed on Com- levels. Larvae and adults feed on the foliage of their melinaceae or Poaceae. The larvae of some species are host. Pupation occurs in the soil. Some species use leafminers whereas others cover themselves with excreta. defensive chemicals for protection (Jolivet and Hawkes- Pupation occurs in the soil (Jolivet and Hawkeswood wood 1995). 1995). - Adults of almost all the 5,800 des- Synetinae - The Synetinae is a group of nine poorly cribed species of Galerucinae feed on dicotyledons, but known species worldwide. The larvae feed on the roots some feed on pollen of a variety of grasses. Larval of a wide variety of plants. Adult females scatter their biology is very diverse in this group. Some species are eggs on the soil (Jolivet and Hawkeswood 1995). root feeders, others leafminers, whereas still others are Clytrinae - The larvae of many of the 1,000 free-living leaf feeders. Leaf-feeding larvae are often described worldwide Clytrinae species are associated gregarious. Adults are leaf or pollen feeders. Some of

235 the most serious plant pests in the world are in this group not only to their relative abundance but to the ease of (Jolivet and Hawkeswood 1995). morphospecies sorting by a nonspecialist. These factors Alticinae - The Alticinae (flea beetles) is the largest make Chrysomelidae an excellent candidate for an subfamily, with 514 genera and more than 7,000 known indicator species assemblage for natural area monitoring. species. Habits are highly varied within this group. Larvae are leafminers, fruit miners, stem borers, flower PLUMMERS ISLAND, MARYLAND or bud miners, root feeders, or leaf feeders. Adults are Plummers Island is a 3.6-ha (8.9-acre) island in the primarily leaf feeders and very host specific. Many flea Potomac River just east of the American Legion Bridge beetles employ reflex bleeding, escape mechanisms (1-495). The island and 15.6 ha (38.5 acre) adjacent on (jumping), and flight for protection. Some genera or the Maryland mainland have been a field laboratory of species are brachypterous or apterous (Jolivet and the Washington Biologists' Field Club since 1901. In Hawkeswood 1995). 1959 the National Park Service purchased the mainland Hispinae - All but one North American genus area and received the island as a gift with the provision (Stenispd) of Hispinae are leafminers as larvae. Many of that the club could continue to conduct research on it the 3,000 known species are associated with various (Long 1966). With the activity of club members, this site Poaceae, Fabaceae, and Asteraceae. Eggs are laid in host is one of the best collected and studied areas in North plant tissue and pupation occurs in the leaf mine. All America. North American species with known biology are Maxon (1935), Krombein (1963), Manville (1968), univoltine (Jolivet and Hawkeswood 1995). and Erwin (1981) have documented the vegetational and - The tortoise beetles are an interesting topographical changes to the island since 1901, which group of 3,000 described species usually associated with we summarize next. The island is an elongated triangle the Convolvulaceae and Solanaceae in North America. above the fall line of the Potomac River and below Great Larvae are free-living leaf feeders often found on the Falls. The highest point is 38 m (124 ft) above sea level same plant as the adults. The caudal fork on the last and about 23 m (75 ft) above mean low water mark, a abdominal segment of larvae carries a fecal shield for second knoll is 30.5 m (i=QO ft) in elevation. There are protection (Jolivet and Hawkeswood 1995). several rocky bluffs, ridges, and knolls with vegetation currently dominated by oak (Quercus sp.), hickory Geographical Distribution (Carya sp.), and American hornbeam (Carpinus carolin- On a worldwide basis, chrysomelids occur in all iand) interspaced with small shrubs and herbaceous biogeographic regions. The number of species is greatest- vegetation. The canopy cover is nearly 100%. The west in the tropics but species may be found in the tundra. end qf the island contains a small area of coarse alluvial Distributional data have already been published for most sand with similar deposits along the channel separating species, which adds to the desirability of their use as the island from the Maryland mainland and on the entire indicators. eastern end of the island. There are also mudflats along the river. Both the mudflats and sandy areas are subject Ease of Capture to periodic flooding. A 1.2-ha (3-acre) floodplain once Adult chrysomelids are easy to capture. The only existed along the river side (Maxon 1935). equipment generally needed is a sweep net and beating As seen from the 1905 photographs in Manville sheet. Specimens can be collected live for later release or (1968) and Erwin (1981), most of the upland and preserved in alcohol. Most species are relatively abun- western portion of the island had few trees. The flood- dant, so the removal of specimens will not adversely plain contained sycamore (Platanus occidentalis) and affect populations. other deciduous species unidentifiable from the photographs. The ridge contained red cedar (Juniperus Interaction with the Rest of the Ecosystem virginiana) and a few deciduous trees. The Maryland In the tropics chrysomelids have been found to be an mainland to the canal towpath had been cleared for excellent indicator of local species richness (Farrell and agriculture. The Virginia mainland was thickly covered Erwin 1988; Basset and Samuelson 1996). This is due with deciduous trees. The island and mainland were left

236 1903 11 13 15 17 19 20 97

Figure 1. The number ofchrysomelid species collected on Plummers Island, Maryland, 1901-1^20 and 1997. to revert to forest species. The Washington Biologists' species of Chrysomelidae from Plummers Island. Dates Field Club's policy is not to manage for particular of collection ranged from 1901 to 1972. The 1997 vegetation but to allow natural succession of whatever survey resulted in 655 specimens representing 40 species, species find their way to the island. 8 of which had never been collected on or reported from In April 1997, a project was started to inventory the Plummers Island. This brings the total number of chrysomelid fauna of Plummers Island. Beetles were species to 147 (Table 1). collected by sweeping and beating vegetation and by An analysis of the historic collection data (1901- visual examination of known chrysomelid host plants. 1920) shows that the species documentation on the island One evening was spent black lighting and visually was uneven (Fig. 1). The years 1901-1920 were used examining known chrysomelid host plants with a because there was a sufficient number of specimens headlamp. collected to make data analysis feasible. There are only At the same time, the insect collection at the about 20 specimens in the NMNH for the years 1921- National Museum of Natural History (NMNH), Smith- 1996. The most productive year was 1905, in which 68 sonian Institution, was examined for specimens collected species (38 previously unreported [new]) were collected. on Plummers Island. Label data were recorded from Other productive years were 1907 (39 species, 7 new), these specimens for comparison with material collected 1902 (38 species, 35 new), 1906 (35 species, 9 new), during 1997. The expectation was a decrease in the 1908 (32 species, 5 new), and 1913 (30 species, 1 new). number of chrysomelid species found and a turnover in The results of the 1997 survey (40 species, 8 new) com- species composition as the island changed from open pare favorably with these data. juniper-grassland to submature oak-hickory-maple forest. One explanation for the differences in the number of Examination of the NMNH collection resulted in 140 species collected is that previous collectors sometimes

237 Table 1. Chrysomelidae known to occur on Plummers Island, Maryland.

Subfamily Species Historic 1997 Donaciinae metallica (Ahrens) X Orsodacninae Orsodacne atra (Ahrens) X Criocerinae Lema trivittata trivittata Say X Criocerinae Neolema sexpunctata (Olivier) X X Criocerinae Oulema cornuta (Fab.) X Criocerinae Oulema melanopus (L.) X Criocerinae Oulema sayi (Crotch) X X Clytrinae laticlavia laticlavia Forster X Clytrinae quadriguttata quadriguttata (Olivier) X Clytrinae omogera omogera (Lacordaire) X Cryptocephalinae lituratus (Fab.) X Cryptocephalinae Bassareus mammifer (Newman) X Cryptocephalinae auratus (Fab.) X X Cryptocephalinae scutellaris (Fab.) X Cryptocephalinae saponatus (Fab.) X Cryptocephalinae Pachybrachis bivittatus (Say) X Cryptocephalinae Pachybrachis cephalicus Fall *"• X Cryptocephalinae Pachybrachis femoratus (Olivier) X Cryptocephalinae Pachybrachis luctuosus Suffrian X Cryptocephalinae Pachybrachis mnigrum (Melsheimer) X Cryptocephalinae Pachybrachis pectoralis (Melsheimer) X Cryptocephalinae Pachybrachis relictus Fall X Cryptocephalinae Pachybrachis spumarius Suffrian i, x Cryptocephalinae Pachybrachis subfasciatus LeConte V. X Cryptocephalinae Pachybrachis tridens (Melsheimer) X Cryptocephalinae Pachybrachis trinotatus (Melsheimer) X Chlamisinae foveolatus (Knoch) X X Chlamisinae dispar Lacordaire X Chlamisinae Exema elliptica Karren X Chlamisinae bebbianae (Brown) X Chlamisinae Neochlamisus bimaculatus Karren X Chlamisinae Neochlamisus platani (Brown) X Eumolpinae clypealis (Horn) X X Eumolpinae Brachypnoea puncticollis (Say) X Eumolpinae Brachypnoea tristis (Olivier) X Eumolpinae auratus (Fab.) X Eumolpinae brunnea Fab. X Eumolpinae Colaspis favosa Say X Eumolpinae longipes Melsheimer X Eumolpinae Fidia viticida Walsh X X Eumolpinae pubescens (Fab.) X Eumolpinae marcassita (Crotch) X Eumolpinae Graphops pubescens (Melsheimer) X Eumolpinae quadrinotata (Say) X X Eumolpinae Paria sexnotata (Say) X X Eumolpinae picipes (Olivier) X X Eumolpinae Rhabdopterus praetextus (Say) X Eumolpinae globosa (Olivier) X

238 I Table 1 (continued)

Subfamily Species Historic 1997 Eumolpinae tricolor (Fab.) X X Eumolpinae decemnotata (Say) X Eumolpinae Xanthonia villosula (Melsheimer) X Eumolpinae Xanthonia sp. X Chrysomelinae bidenticola Brown X Chrysomelinae Calligrapha californica coreopsivora Brown X Chrysomelinae Calligrapha multipunctata bigsbyana (Kirby) X Chrysomelinae Calligrapha Philadelphia (L.) X Chrysomelinae Calligrapha scalaris (LeConte) X X Chrysomelinae quadrigemina (Suffrian) X Chrysomelinae scripta Fab. X Chrysomelinae cyanea Melsheimer X Chrysomelinae Labidomera clivicollis (Kirby) X Chrysomelinae decemlineata (Say) X Chrysomelinae Phaedon viridis Melsheimer X Chrysomelinae Phratora americana (Schaeffer) X Chrysomelinae suturalis suturalis (Fab.) X Galerucinae Acalymma vittatum (Fab.) X X Galerucinae Cerotoma trifurcata (Forster) X Galerucinae Diabrotica undecimpunctata howardi Barber X X Galerucinae Galerucella nymphaeae (L.) X Galerucinae LeSage X Galerucinae Ophraella conferta (LeConte) X

Galerucinae Ophraella notata (Fab.) X is Galerucinae Phyllecthris dorsalis (Olivier) x V- Galerucinae Phyllecthris gentilis LeConte * X Galerucinae Scelolyperus liriophilus Wilcox X Galerucinae Tricholochmaea rufosanguinea (Say) X Galerucinae Tricholochmaea tuberculata (Say) X Alticinae chalybea Illiger • X Alticinae Altica ignita Illiger X Alticinae Altica kalmiae Melsheimer X X Alticinae Altica woodsi Isley X Alticinae Aphthona insolita (Melsheimer) X Alticinae rhois (Forster) x ,. Alticinae Capraita obsidiana obsidiana (Fab.) X Alticinae Capraita quercata (Fab.) X X Alticinae Capraita sexmaculata (Illiger) X X Alticinae Capraita subvittata (Horn) X X Alticinae Capriata suturalis (Fab.) X Alticinae confinis Crotch X Alticinae Chaetocnema crenulata Crotch X Alticinae Chaetocnema denticula (Illiger) X X Alticinae Chaetocnema quadricollis Schwarz X X Alticinae Crepidodera browni Parry X Alticinae Crepidodera nana (Say) X Alticinae Derocrepis erythropus (Melsheimer) X Alticinae borealis (Chevrolat) X

239 Table 1 (continued)

Subfamily Species Historic 1997 Alticinae discoidea abbreviata Melsheimer X Alticinae Disonycha discoidea discoidea (Fab.) X Alticinae Disonycha glabrata (Fab.) X X Alticinae Disonycha xanthomelas xanthomelas (Dalman) X Alticinae Distigmoptera pilosa (Illiger) X Alticinae brevis Schwarz X Alticinae Epitrix cucumeris (Harris) X X Alticinae Epitrix fasciata Blatchley X Alticinae Epitrix fuscula Crotch X X Alticinae Epitrix hirtipennis (Melsheimer) X Alticinae Epitrix nitens (Horn) X Alticinae Glyptina brunnea Horn X Alticinae Glyptina spuria LeConte X Alticinae Hornaltica atriventris (Melsheimer) X Alticinae Kuschelina gibbitarsa (Say) X Alticinae Kuschelina petuarista (Fab.) X Alticinae Kuschelina thoracica (Fab.) X Alticinae Kuschelina vians (Illiger) X X Alticinae Longitarsus sp. 1 X Alticinae Longitarsus sp. 2 X Alticinae Luperaltica nigripalpus (LeConte) X Alticinae Mantura floridana Crotch X Alticinae Monomacra iris (Olivier) X Alticinae Orthaltica copalina (Fab.) • i x Alticinae Pachyonychus paradoxus Clark X Alticinae Palaeothona picta (Say) X Alticinae Phyllotreta bipustulata (Fab.) X Alticinae Phyllotreta conjuncta Gentner X Alticinae Phyllotreta liebecki Schaeffer X Alticinae Phyllotreta striolata (Fab.) • X Alticinae Phyllotreta sp. 1 X Alticinae Strabala rufa (Illiger) X Alticinae blanda Melsheimer X Alticinae Systena hudsonias (Forster) X X Alticinae (Illiger) ur X Hispinae Baliosus nervosus (Panzer) X Hispinae Chalepus bacchus (Newman) X Hispinae Chalepus bicolor (Olivier) X Hispinae Microrhopala xerene (Newman) X Hispinae Octotoma plicatula (Fab.) X X Hispinae dorsalis (Thunberg) X X Hispinae Odontota mundida (Sanderson) X Hispinae Odontota scapularis (Olivier) X Hispinae Stenispa metallica (Fab.) X Hispinae Sumitrosis inaequalis (Weber) X X Hispinae Sumitrosis rosea (Weber) X X Hispinae Xenochalepus potomacus Butte X

240 Table 1 (continued)

Subfamily Species Historic 1997 Cassidinae Charidotella bicolor (Fab.) X X Cassidinae cassidea (Fab.) X Cassidinae guttata (Olivier) X X Cassidinae Plagiometriona clavata (Fab.) X X

labeled material from the Maryland mainland as well as pennis) are relatively common species that somehow had the island proper as Plummers Island. The present not been collected on or reported from Plummers Island. survey was restricted to the island itself. The elimination The vegetational changes on the island have affected of the mainland section reduces the number of habitats the composition of the chrysomelid fauna. Several host available for chrysomelids. A second explanation for the plants not found during the 1997 survey reduced the differences in the number of species collected is the number of species collected. The major deletion was wil- amount of time spent on the island. An analysis of the low (Salix sp.), which supported seven species of leaf collection dates from the historic specimens showed that beetles. Another major host plant not found was rag- in 1905, the only year yielding more chrysomelid species weed (Ambrosia artemisiifolid), which supported four than the current survey, chrysomelids were collected on chrysomelid species. 24 different dates. Other years with high yields also had The majority of species not collected in 1997 had more dates of collection: 25 for 1907, 21 for 1908, and their host plant present on the island. These species may 17 for 1913. The current survey spent 10 days (average not have been collected for several reasons. The major of 5 hr/day) on the island. It is not possible to determine reason is that a number of the species are inhabitants of the number of hours the earlier collectors spent on the fields. Whereas the host plant survives in the first 5-10 island so an exact comparison of results per day cannot m (16-33 ft) of woods, the beetles are not found unless be made. the host is in direct sunlight: <.?b> Species such as The 32 historic species collected in 1997 fall into and Brachypnoea puncticollis are three categories. The first is the woods and woods edge good examples. Most Cryptocephalinae also fit this pat- species such as Tymnes tricolor, Rhabdoptems picipes, tern. Another possible reason is the collection methods and the five hispines species. The second is the open- employed. Whereas earlier collectors used various field species that still persist in the sunnier locations on extraction methods (such as Berlese funnels) and light the island where their host plant occurs. Examples of trapping, the 1997 survey relied mostly on sweeping and this group are Systena hudsonias, Epitrix cucumeris, and beating foliage and visual inspection of plants. However, Disonychaglabrata. The third category is the generalists use of the earlier two methods may have resulted in such as Acalymma vittatum and Diabrotica undecim- additional species. One evening of the survey was spent punctata howardi, which are collected as they feed on black lighting. While no chrysomelid species were pollen of various flowers. collected, nocturnal species such as Of the eight species collected on the island for the probably still occur on the island. During the black light first time, only two are recent adventives. Oulema evening some time was spent examining foliage with a melanopus was first collected in Maryland in 1969 and headlamp. Two species of chrysomelids (Neolema now occurs throughout the state (Staines 1997). sexpuncatata and Oulema sayi) were collected. How- Chrysolina quadrigemina was introduced into Ontario, ever, neither species had been found while sweeping and Canada, in the 1950s for biological control of examining foliage that afternoon. . The first specimens were found in Maryland A potential error to the preceding data analysis is in 1991 (Hoebeke 1993). This is the second record of the that not all Plummers Island material is deposited in the species for Maryland. The other six species (Lema NMNH. From the literature reviewed for this project two trivittata trivittata, Altica woodsi, Capriata suturalis, historic Plummers Island records of species (Plateumaris Chaetocnema confinis, C. crenulata, and Epitrix hirti- metallica and Exema ellipticd) were obtained. Addi-

241 tional material is probably present in museums surveys and data analysis. CSIRO, Canberra, . throughout the United States. Some of the records Braithwaite, R. W., L. Miller, and J. T. Wood. 1988. The ecological presented as new to the island for 1997 may have been structure of termites in the Australian tropics. Australian Journal of collected earlier, but the specimens have not been Ecology 13:379-391. examined by the authors or reported in the literature. Byrne, D. N., E. H. Carpenter, E. M. Thomas, and S. T. Cotty. 1984. These holdings may>_ also contain additional historic Public attitudes toward urban arthropods. Bulletin of the Entomological Society of America 30:40-44. records that may raise the total number of species from the island and affect the analysis of the number of species Coulson, R. N., and D. A. Crossley. 1987. What is insect ecology? A commentary. Bulletin of the Entomological Society of America 33: found each year. 64-68.

DeBach, P., and D. Rosen. 1991. Biological control by natural enemies. CONCLUSIONS Second edition. Cambridge University Press, New York. It is premature to draw far-reaching conclusions Downie, N. M., and R. H. Arnett. 1996. The beetles of northeastern North from 1 year of field work. The 147 chrysomelid species America. Sandhill Crane Press, Gainesville, Florida. known from Plummers Island is impressive, with 39% of the species known from Maryland found in less than 20 Ehrlich,P. R., and D. Murphy. 1987. Conservation lessons from long-term studies of checkerspot butterflies. Conservation Biology 1:122-131. ha (49 acres). Further survey work in 1998 using a wider variety of survey methods will give a much more Erwin, T. L. 1981. Natural history of Plummers Island, Maryland. XXVI. The ground beetles of a temperate forest site (Coleoptera: Carabidae): An complete and detailed picture of the Chrysomelidae of analysis of fauna in relation to size, habitat selection, vagility, seasonality, Plummers Island. Inventories have been published for a and extinction. "Bulletin of the Biological Society of Washington 5:106- 224. number of plant and animal groups on Plummers Island (Hood 1917;McAtee and Caudell 1917; Killip and Blake Farrell, B. D., and T. L. Erwin. 1988. Leaf-beetle community structure in 1935, 1953; Leonard and Killip 1939; Leonard and an Amazonian rainforest canopy. Pages 73-90 in P. Jolivet, E. Petitpierre and T. H. Hsiao, editors. Biology of Chrysomelidae. Kluwer Academic Pierce 1939; Leonard 1966; Manville 1968;Erwin 1981). Publishers, Dordrecht, Netherlands. These detailed data will enable a thorough analysis of the Favila, M. E., and G. Halffter.( 1997. The use of indicator groups for use of chrysomelids as an indicator species assemblage measuring biodiversity as relate"d4to community structure and function. for natural area monitoring. Acta Zoologica Mexicana 72:1-25. Frost, S. W. 1959. Insect life and insect natural history. Second edition. ACKNOWLEDGMENTS Dover Publications, New York.

We thank S. Lingafelter, U.S. Department of Agri- Hafernik, J. E. 1992. Threats to invertebrate biodiversity for conservation culture, Systematic Entomology Lab, for access to the strategies. Pages 171-195 in P. L. Fielder and S. K. Jain, editors. NMNH collection. D. H. Nicolson, Department of Bot- Conservation biology: the theory and practice of nature conservation, preservation and management. Chapman and Hall, New York. any, Smithsonian Institution, gave valuable assistance on the history and plants of Plummers Island. W. E. Hawkins, C. P., and J. A. MacMahon. 1989. Guilds: the multiple meanings of a concept. Annual Review of Entomology 34:423-451. Steiner, Department of Entomology, Smithsonian Insti- tution, collected some chrysomelids on his visits to Hoebeke, E. R. 1993. Establishment of Urophora quadrifasciata (Diptera: ) and Chrysolina quadrigemina (Coleoptera: Plummers Island. This research was funded in part by a Chrysomelidae) in portions of the eastern United States. Entomological grant from the Washington Biologists' Field Club. News 104:143-152.

Hood, J. D. 1917. An annotated list of the Thyansoptera of Plummer's LITERATURE CITED Island Maryland. Insecutor Inscitiae Menstruus 5:53-65. Amett, R. H. 1985. American insects: a handbook of the insects of America north of Mexico. Van Nostrand Reinhold Co., New York. Howarth, F. G., and G. W. Ramsay. 1991. The conservation of island insects and their habitats. Pages 71-108 in N. M. Collins and J. A. Basset, Y., and G. A. Samuelson. 1996. Ecological characteristics of an Thomas, editors. The conservation of insects and their habitats. Academic arboreal community of Chrysomelidae in Papua New Guinea. Pages 234- Press, New York. 262 in P. H. A. Jolivet and M. L. Cox, editors. Chrysomelidae Biology, Volume 2: Ecological studies. SPB Academic Publishing. Amsterdam, Hutto, R. L., S. Reel, and P. B. Landres. 1987. A critical evaluation of the Netherlands. species approach to biological conservation. Endangered Species Update 4:1-4. Braithwaite, R. W. 1991. Fauna and habitat surveys as ecological pathfinders. Pages 23-28 in C. R. Margules and M. P. Austin, editors. Jolivet, P., and T. J. Hawkeswood. 1995. Host-plants of Chrysomelidae of Nature conservation: cost effective conservation: cost effective biological the world. Backhuys Publishers, Leiden, Netherlands.

242 Kim, K. C. 1993. Insect pests and evolution. Pages 3-26 in K. C. Kim and McNaughton, S. J. 1989. Ecosystem and conservation in the twenty-first B. A. McPheron, editors. Evolution of insect pests. John Wiley and Sons, century. Pages 109-130 in D. Western and M. C. Pearl, editors. Inc., New York. Conservation in the twenty-first century. Oxford University Press, New York. Killip, E. P., and S. P. Blake. 1935. Natural history of Plummers Island. II. Flowering plants and ferns. Proceedings of the Biological Society of Metcalf, R. L. 1986. Foreword. Pages vii-xv in J. L. Krysan and T. A. Washington 48:118-137. Miller, editors. Methods for the study of pest Diabrotica. Springer-Verlag, New York. Killip, E. P., and S. P. Blake. 1953. Natural history of Plummers Island. X. Flowering plants and ferns. Supplement I. Proceedings of the Biological Miller, J. C. 1993. Insect natural history, multi-species interactions, and Society of Washington 66:31-38. biodiversity in ecosystems. Biodiversity and Conservation 2:233-241.

Klausnitzer, B. 1981. Beetles. Exeter, New York. Morris, M. G., N. M. Collins, R. I. Vane-Wright, and J. Waage. 1991. The utilization and value of non-domesticated insects. Pages 319-349 in N. M. Kreman, C. 1992. Assessing the indicator properties of species assemblages Collins and J. A. Thomas, editors. The conservation of insects and their for natural areas monitoring. Ecological Applications 2:203-217. habitats. Academic Press, London.

Kreman, C. 1994. Biological inventory using target taxa: a case study of Murphy, D. D., K. E. Freas, and S. B. Weiss. 1990. An environment- the butterflies of Madagascar. Ecological Applications 4:407-422. metapopulation approach to population viability analysis for a threatened invertebrate. Conservation Biology 4:41-51. Kreman, C., R. K. Colwell,T. L. Erwin, D. D. Murphy,R.F.Noss,andM. A. Sanjayan. 1993. Terrestrial assemblages: their use in Noss, R. F. 1990. Indicators for monitoring biodiversity: a hierarchical conservation planning. Conservation Biology 7:796-808. approach. Conservation Biology 4:355-364.

Krombein, K. V. 1963. Natural history of Plummers Island, Maryland. Olembo, R. 1991. Importance of microorganisms and invertebrates as XVII. Annotated list of the wasps (: Bethyloidea, Scolioidea, components of biodiversity. Pages 7-16 in D. L. Hawksworth, editor. The Vespoidea, Pompiloidea, Spechoidea). Proceedings of the Biological biodiversity of microorganisms and invertebrates: its role in sustainable Society of Washington 76:255-280. agriculture. CAB International, Wallingford, England.

Kiihnelt, W. 1976. Soil biology, with special reference to the animal Oliver, I., and A. J. Beattie. 1993. A possible method for the rapid kingdom. Second edition. Michigan State University Press, East Lansing. assessment of biodiversity. Conservation Biology 7:562-568.

Landres, P. B., J. Verner, and J. W. Thomas. 1988. Ecological uses of Paoletti, M. G., M. R. Fauretto, B. R. Stinner, F. F. Purrington, and J. E. vertebrate indicator species: a critique. Conservation Biology 2:316-328. Bater. 1991. Invertebrates as bioindicators of soil use. Agriculture, Ecosystems and Environment 34:341-362. Leonard, E. C., and E. P. Killip. 1939. Natural history of Plummers Island, ^, Maryland. VIII. Lichens. Proceedings of the Biological Society of Pasteels, J. M., J. Braekman, andD. Daloze. 1988. Chemical defense in Washington 52:23-26. - the Chrysomelidae. Pages 233-252 in P. Jolivet, E. Petitpierre, and T. H. Hsiao, editors. Biology of Chrysomelidae. Kluwer Academic Publishers, Leonard, E. C., and M. E. Pierce. 1939. Natural history of Plummers Dordrecht, Netherlands. Island, Maryland. VIII. Hepaticae. Proceedings of the Biological Society of Washington 52:21-22. Pasteels, J. M., M. Rowell-Rahier, J. Braekman, and D. Daloze. 1994. Chemical defense of adult leaf beetles updated. Pages 289-301 in P. H. Leonard, M. D. 1966. Natural history of Plummers Island, Maryland. XIX. Jolivet and M. L. Cox, editors. Novel aspects of the biology of Annotated list of the aphids (Homoptera: Aphididae). Proceedings of the Chrysomelidae. Kluwer Academic Publishers, Dordrecht, Netherlands. Biological Society of Washington 79:117-126. Pearson, D. L. 1994. Selecting indicator taxa for the quantitative Long, E. J. 1966. The Island. American Forests, February 1966:22-24. assessment of biodiversity. Philosophical Transactions of the Royal Society of London 6345:75-79. Lopatin, I. P. 1977. Leaf beetles (Chrysomelidae) of central Asia and y Kazakhstan. Academy of Sciences of the Union of Soviet Socialist Pearson, D. L., and F. Cassola. 1992. World-wide species richness patterns Republics, Institute of Zoology, Keys to the Fauna of the USSR 113, of tiger beetles (Coleoptera: Cicindelidae): indicator taxon for biodiversity Leningrad, USSR. and conservation studies. Conservation Biology 6:376-391.

Magurran, A. E. 1988. Ecological diversity and its measurement. Princeton Pimentel, D., U. Stachow, D. A. Takacs, H. W. Brubaker, A. R. Dumas, University Press, Princeton, New Jersey. J. J. Meaney, J. A. S. O'Neil, D. E. Onsi, and D. B. Corzilius. 1992. Conserving biological diversity in agricultural/forestry systems. Manville, R. H. 1968. Natural history of Plummers Island, Maryland. XX. BioScience 42:354-362. Annotated list of the vertebrates. Special Publication of the Washington Biologists' Field Club. Pyle, R. M. 1976. Conservation of Lepidoptera in the United States. Biological Conservation 9:55-75. Maxon, W. R. 1935. Natural history of Plummers Island, Maryland. I. Introduction. Proceedings of the Biological Society of Washington Samways, M. J. 1989. Insect conservation and the disturbance landscape. 48:115-117. Agriculture, Ecosystems and Environment 27:183-194.

McAtee, W. L., and A. N. Caudell. 1917. First list of the Dermaptera and Samways, M. J. 1992. Some comparative insect conservation issues of Orthoptera of Plummers Island, Maryland. Proceedings of the north temperate, tropical, and south temperate landscapes. Agriculture, Entomological Society of Washington 19:100-122. Ecosystems and Environment 40:137-154.

243 Seeno, T. N., and J. A. Wilcox. 1982. genera (Coleoptera: Walker, B. H. 1992. Biodiversity and ecological redundancy. Chrysomelidae). Entomography 1:1-222. Conservation Biology 6:18-23.

Selman, B. J. 1988. Viruses and Chrysomelidae. Pages 379-387 in P. White, R. E. 1996. Leaf beetles as biological control agents against Jolivet, E. Petitpierre, and T. H. Hsiao, editors. Biology of Chrysomelidae. injurious plants in North America. Pages 373-399 in P. H. A. Jolivet and Kluwer Academic Publishers, Dordrecht, Netherlands. M. L. Cox, editors. Chrysomelidae biology, Volume 2: Ecological studies. SPB Academic Press, Amsterdam, Netherlands. Staines, C. L. 1997. Cereal leaf beetle (Coleoptera: Chrysomelidae) as a pest of ornamental grasses. Proceedings of the Entomological Society of Wilson, E. O. 1987. The little things that run the world. Conservation Washington 99:376. Biology 1:344-346.

Swift, M. J., and J. M. Anderson. 1989. Decomposition. Pages 547-569 in Wilson, E. O., and F. M. Peter, editors. 1988. Biodiversity. National H. Lieth and M. J. A. Werger, editors. Tropical rain forest ecosystems, Academy Press, Washington, D.C. biogeography and ecological studies. Elsevier, Amsterdam, Netherlands

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