Life History and Ecology of Acroneuria Carolinensis (Banks) in Panther Creek, Nicholas County, West Virginia (Plecoptera: Perlidae)

Life History and Ecology of Acroneuria Carolinensis (Banks) in Panther Creek, Nicholas County,... BY D. A. SCHMIDT D. C. TARTER Department of Biological Sciences Marshall University Huntington, WV 25701 INTRODUCTION Life history information is important to sampling techniques taxonomy, production, feeding, bioassay, environmental disturbance management studies. There is a basic lack of life history information that is needed by researchers resource managers (Rosenberg, 1979). Stoneflies are an important part of the stream ecosystem are useful as water quality indicators. Few studies concerning the life histories of Acroneuria spp. have been carried out. Siegfried Knight (1978) studied the life history of Acroneuria (Calineuria) californica Banks. Most other ecological data has been limited to A. abnormis A. lycorias concentrates on specific areas such as food habits, drift predator-prey relations. The objective of this investigation was to describe the life history of Acroneuria carolinensis with specific reference to: l) naiad age growth, 2) sex ratio, 3) food preference 4) emergence. TAXONOMY DISTRIBUTION Illies (1966) presented a review of the taxonomic changes of A croneuria carolinensis. A croneuria carolinensis was first described as a new species by Banks (1905) as Perla carolinensis from Black Mountain, North Carolina. In 1918, Navas placed it in another genus calling the insect Nostura carolinensis. Ricker (1935) assigned new nomenclature designated the insect as A croneuria custae. Claassen (1940) restored the specific name thus recognizing Acroneuria carolinensis as valid. *Manuscript received by the editor August 5, 1985 A croneuria carolinensis has been recorded from 11 states three Canadian provinces. It ranges from Manitoba, Ontario Quebec in southern Canada to Tennessee South Carolina in the United States (Peckarsky, 1979). MATERIALS METHODS Panther Creek originates in Nicholas County, 31/2 miles (5.6 km) southeast of the Greenbrier County line, near Saxman, West Virginia at an elevation of 3000 feet (914 m). Panther Creek flows northward, emptying into the Gauley River at an elevation of 820 feet (250 m); it has a total fall of 1180 feet. (360 m) a total length of 9.6 miles (15.4 km). The drainage basin area is 16.88 square miles (43.7 m2) (Reger, 1921). The study area is located along Route 39, 13.7 miles (22.1 km) west of the junction of Routes 19 39 at Summersville, at an elevation of 2200 feet (671 m). Collections were made in a riffle area 161 feet (49 m) below a concrete dam. The riffle was 36 feet (11 m) long had an average width of 25.6 feet (7.8 m). Substrate consists of rocks with an approximate size range of 6 to 18 inches (15 to 46 cm) in diameter. Qualitative samples were collected monthly from December 1984 to November 1985. After disturbing the substrate, a fine meshed dredge (mesh size: 4 mm, December-May; mm, June-November) was held immediately below the disturbed area to collect the drifting naiads. Contents of the dredge were emptied into a white enamel pan to facilitate sorting. Naiads were immediately killed preserved in 70 percent ethyl alcohol. Temperature of the stream was recorded monthly using a Fisher instantaneous thermometer. During the emergence period, temperature was recorded weekly. Water chemistry was measured monthly using a Hach chemical kit (Model AL-36B). Dissolved oxygen, carbon dioxide, hardness, alkalinity pH were measured in the field. All variables were measured in mg/1 except for pH. Total length (excluding antennae cerci) was measured by placing the naiad on a plastic millimeter ruler viewing under a binocular dissecting scope. Naiads were measured to the nearest 0.5 mm placed in mm class intervals. Length-frequency histo- grams were produced for each month. Number of age classes was determined based on the distribution of the body length. Population range diagrams (Hubbs Perlmutter, 1942) were used to show monthly head width variations between males females. Early instar naiads too small to sex (usually < 6.0 mm) were excluded from the analysis. Head width was measured to the nearest 0.05 mm using an ocular micrometer in a binocular dissecting microscope. Head width was used as a size stard because it changes least during preservation (Britt, 1953). Monthly growth rates were calculated as a percent increase in mean head width from one month to the next for males females. An estimation of the number of instars was calculated using the Janetschek method (Janetschek, 1967). Head width frequency histograms were produced for all collections combined. A trend-line for population growth was then calculated using a gliding mean over five successive class frequencies at a time. Gliding means were then subtracted from the frequency for each size class. These periodic maxima minima were ploted positive peaks were counted to determine number of instars. Sex of naiads was determined by examining the posterior margin of the 8th abdominal sternite. A chi-square test was performed on 72 males 152 females. Deviation from the expected 1" sex ratio was tested at the 0.05 confidence level. Naiad food preference was determined by examining the contents of the foregut. Twelve foreguts were analyzed each month. After the foreguts were removed by dissection, contents of the foregut were gently scraped onto a glass slide examined under a binocular dissecting scope. Food items were sorted identified to the lowest taxonomic unit possible. Taxa, number of taxa per foregut number of foreguts with the item were recorded. The mean number of a particular taxon per foregut the percentage of foreguts in which that taxon occurred (percent frequency of occurrence) were calculated on a monthly seasonal basis. Using a Ward ultraviolet light trap (8 watts), an attempt was made to collect emerging adults at the study area. On 31 May 1984, the trap was set up from 10:00 to 12:00 p.m. During May June, the banks of Panther Creek were searched for exuviae to determine the emergence period. Distance of exuviae from the stream bank type of substrate on which they were found were recorded. Dec Jan Feb _. rch April ", May "’a-= 35ijun e0 301Aug 350 I Sept Oct Nov 2O Body Length, mm Figure 1. Length-frequency histograms showing monthly distribution of Acro- neuria carolinensis naiads. Schmidt & Tarter Acroneuria carolinensis Fecundity was determined by direct egg count. Eggs were dissected out from 19 adults. They were placed in a syracuse watch glass counted under a binocular dissecting scope. Regression analysis was used to determine the relationship between total body length number of eggs produced. A correlation coefficient (r) was calculated to determine the strength of the relationship. The diameter length of 125 eggs from five adults were measured using an ocular micrometer in a binocular dissecting scope. Eggs were measured to the nearest 0.01 mm. Average egg size was calculated. RESULTS DISCUSSION Stream environment. The mean water temperature at Panther Creek during the study period was 8.3 C. The temperature ranged from 0.0 in January to 16 C in June. During emergence studies, a high temperature of 17 C was recorded on 8 June 1984. Dissolved oxygen was high, ranging from 7 to 13 mg/1 (X 9.4 mg/1). Carbon dioxide ranged from 10 to 85 mg/1, with a mean of 61.5 mg/1. Alkalinity ranged from 0.0 to 102.6 mg/1 (X 29.9 mg/1) during 1982, according to Pettry (1983). Total hardness ranged from 34.2 to 224.9 mg/1 (X 122.8 mg/1). The pH had a mean value of 6.9 ranged from 6.3 to 7.2. Length-frequency histograms. Length-frequency analysis indicated a two-year life cycle (Figure 1). Body length ranged from 3.5 to 26.0 mm. The largest naiads were collected in February, April May. Larger naiads were absent following the 20 May collection, when emergence had occurred. There was approximately an 11 week egg development period before recruitment of the new age class. The smallest earliest naiads were first collected in late August. The existence of a 6 mm naiad in January suggested some evidence that a three-year life cycle’,may be possible. Absence of additional naiads of this size could have been due to the larger mesh size dredge used during the winter collections. Harper Magnin (1969) suggested three-year life cycles for A. abnormis A. lycorias. They also indicated that the number of naiads collected was too small to make a definite conclusion. Sheldon (1969) reported a life cycle of three years for Calineuria californica at an elevation of 2200 m. Heiman Knight (1975) Siegfried Knight (1978) both suggested a two-year life cycle at lower elevation for C. californica. Allen Tarter (1985) reported a two-year life cycle for Eccoptura’ xanthanes (formerly A. xanthanes). Growth. Population range diagrams (Figure 2) showed a wide range in head width. The largest female head width was 6.22 mm occurred in October. The largest male head width was 5.07 mm occurred in December. Females exhibited greater mean head widths than males (Figure 2). Males exhibited greatest growth in August (12%) October (17%). Growth of females was greatest in August (28%) January (13%). The smallest immatures were first collected in August had their greatest growth in October (21%). Following emergence there was a marked decrease in mean head width for males in July (26%) females in June (30%). The population showed a sharp decrease in mean head width in August (48%). This decrease coincided with the recruitment of a new age class. Calineuria californica exhibited its greatest growth in spring when the stoneflies were still small (Siegfried Knight, 1978). Growth declined with an increase in size. In this study C. californiea showed an egg diapause early instars were not collected until February. In laboratory growth studies with C. californica, the greatest growth occurred in the summer, while the least occurred in the winter (Heiman Knight, 1975). The Janetschek method (Janetschek, 1967) indicated that A. carolinensis naiads underwent 25 instars (Figure 3a 3c). A general growth trend using gliding means is shown in Figure 3b. Sex ratio. A chi-square test was applied to 72 male 152 female A. carolinensis naiads. A significant deviation from the expected 1-1 ratio was observed at the 0.05 confidence level. Foregut analysis. Of the 144 foreguts examined, 78 (54%) contained food items. The highest percentage of empty foreguts occurred in April (75%). On a seasonal basis the percent of empty foreguts never exceeded 50 percent. Acroneuria carolinensis naiads were carnivorous, with Diptera (X 6.4, %FO 19.4), plecopterans (X 1, %FO 15.9), ephemeropterans (X 1, %FO 12.5) trichopterans (X 1.3, %FO 5.5) as the most important food items. Diptera was represented by larval chironomid midges. Plecopterans found in the foregut included members from the famijies Capniidae, Leutridae, Nem- Schmidt & Tarter Acroneuria carolinensis ww ’qiplM poex ouridae, Taeniopteryidae Peflodidae. Ephemeropterans included representatives from the genera Ephemerella, Epeorus, Cloeon, Stenonema a member from the family Baetidae. Trichopterans included representatives of the genera Glossosoma, Hydropsyehe Cheumatopsyehe. Results of monthly foregut analysis are presented in Figure 4. Plecopterans ephemeropterans made up the principle components of the diet throughout the year. Dipterans became important in the winter summer, while trichopterans were most important in the summer. Naiads fed most during the winter months with an average of 5.0 food items/stonefly. They fed least during the spring fall with an average of 1.1 food items/stonefly each season. Siegfried Knight (1976a, 1976b) Sheldon (1969) reported dipterans, trichopterans ephemeropterans as the most important food items for C. californica. Sheldon (1969) found that ephemeropterans were a regular component of C. californica’s diet dipterans were important in the winter summer. Siegfried Knight (1976a) stated that dipterans were the most important consistent food item for C. californica. Siegfried Knight (1976b) found that C. californica naiads showed no preference for a particular prey would eat anything available. They also reported a significant correlation between gut diversity benthic diversity. Sheldon (1969) stated that food consumption was low in the summer. In a laboratory study, Heiman Knight (1975) found that C. californica had its greatest food consumption in the summer, with minimal feeding in the winter, at normal environmental temperatures. Johnson (1981) reported that dipterans trichopterans were the primary diet for A. abnormis. The diet was supplemented with ephemeropterans. Phoresy. Larvae of a chironomid midge were observed living phoretically with A croneuria carolinensis naiads. The midges occurred on the prothorax or just beneath the mesothoracic wing pad. The phoretic attachment occurred on nine of 241 (3.7%) naiads examined. Dosdall Mason (1981) reported the chironomid Nanocladius (Plecopteracoluthus) branchicolus living phoretically on A. lycorias. They reported varied percentages of the number of stoneflies bearing the chironomids. The percentages of phoretic cases ranged from 10-50 percent. Rearing emergence. The attempt to collect emerging adults on 31 May 1984 was unsuccessful. Exuviae were collected up to 4.6 lO 23, I’ 1’ 4.0 5,0 Head Width mrn Figure 3. Growth rates of Acroneuria carolinensis naiads from Panther Creek, Nicholas County, West Virginia, 1983-1984: a) frequency of size classes; b) trendline of the population, calculated by gliding means over five successive size-class frequencies at a time; c) periodicity of maximum frequency of size. m from the water surface. They were found clinging to s, rocks, rhododendron stems moss. Based on the number of exuviae collected (33), peak emergence was on 8 June 1984; emergence lasted three weeks. The first exuvium was collected on June the last on 16 June. Emergence peaked with a corresponding peak in Plecoptera 40 Ephemeroptera or_ 41Trichptera Diptera IMI IM1 Month OI Figure 4. Percentage frequency of food items in foreguts of Acroneuria caroli- nensis naiads each month. temperature (17 C) (Figure 5). Mingo (1983) reported A. carol# nensis to be in flight from 12 June to 3 August in Maine. Flight periods for other A croneuria spp. recorded by Mingo (1983) were: A. abnormis, 10 June to 14 July; A. arenosa, 30 June to 3 August; A. lycorias, 10 July. Kondratieff Despins (1983) reported the Schmidt & Tarter Acroneuria carolinensis following flight periods for Acroneuria sp. related genera from Virginia: A. arenosa, late June to early July; A. abnormis, throughout June; Eccoptura xanthanes, late May through mid-July. Allen Tarter (1985) reported E. xanthanes emerged from 11 June to 14 July in Kentucky. In a separate study, A. carolinensis naiads adults were to be collected at Panther Creek in the spring of 1985. On 25 May no final instar naiads were collected. On 2 June a single final instar naiad was found after two hours of sampling. These findings suggested that emergence had taken place in mid-May, three weeks earlier than 1984 emergence. The weather in April 1985 was unseasonably warm, perhaps induced early emergence. Harper Pilon (1971) studied the emergence of A. abnormis for three years (1958, 1959, 1966). They found little temperature difference between the emergence curves, but cooler temperatures in 1958 had delayed emergence for two weeks. Fecundity. Of the 19 adults examined, only seven contained mature eggs. Therefore, mature eggs immature eggs of comparable size were counted. Direct egg count resulted in a range of 10 to 800 eggs (X 239) per female. There was little correlation between body length number of eggs (r 0.56). Egg size. A croneuria carolinensis eggs were oval in shape. Mean length was 0.43 mm (range 0.38-0.48 mm), mean diameter was 0.33 mm (range 0.29-0.38 mm). Stark Gaufin (1976) provided electron micrographs of the eggs gave detailed descriptions. From the material examined by Stark Gaufin (1976), two types of ova were found. They suspect two closely related species are involved suggested additional studies of the complex. SUMMARY The life history ecology of A croneuria carolinensis from Panther Creek, Nicholas County, West Virginia were studied from December 1983 to November 1984. Length-frequency distribution indicated a two-year life cycle. The largest naiads (26.0 mm) were collected in February, April May. Females males exhibited greatest growth in August (28%) October (21%), respectively. Naiads underwent 25 instars. A chi-square test applied to 72 males 152 females showed a deviation (0.05 confidence level) from the expected 1"1 sex ratio. Naiads were carnivorous in their feeding E 10 :11 June Figure 5. Naiad exuviae collected during May June, 1984, showing yearly pattern of emergence of Acroneuria carolinensis. habits. Plecopterans (X 1, %FO 15.9) ephemeropterans (X 1, %FO 12.5) made up the principle components of the diet. Dipterans were important components in the winter summer, while trichopterans became important in the summer. A phoretic relationship between A. carolinensis naiads a chironomid midge was observed on 3.7 percent of the naiads examined. Emergence was between June 16 June; peak emergence occurred on 8 June 1984. Direct egg counts for adult females ranged from 10 to 800 eggs (X- 239) per female. There was littld correlation between body length number of eggs (r 0.56). Mean egg length was 0.43 mm (range 0.38-0.48) mean egg diameter was 0.33 mm (range 0.29-0.38). ACKNOWLEDGMENTS The authors are especially thankful to the following persons for help in this investigation: Dale Adkins, Dean Adkins, Allan Brant, Creda Jim Meadows, Amy Messinger, Brian Reeder Thomas Weaks. Special thanks to Vickie Crager for typing the manuscript. LITERATURE CITED ALLEN, B. L. D. C. TARTER. Life history ecology of Eccoptura xanthanes (Newman) (Plecoptera: Perlidae) from a small Kentucky stream. Proc. Ky. Acad. Sci. (IN PRESS) BANKS, N. Descriptions of new species of neuropterous insects from the Black Mountains, N. C. Am. Mus. Nat. Hist. Bul. 21: 215-218. BRITT, N. W. 1953. Differences between measurements of living preserved aquatic insects caused by injury preservatives. Ecology 34: 802-803. CLAASSEN, P. W. 1940. A catalogue of the Plecoptera of the world. Mem. Cornell Univ. Agric. Exp. Stn. 232: 1-235. DOSDALL, L. M. P. G. MASON. 1981. A chironomid (Nanocladius branchicolus: Diptera) phoretic on a stonefly (Acroneuria lycorias: Plecoptera) in Saskatchewan, Canada. Can. Entomol. 113: 141-148. HARPER, P. E. MAGNIN. 1969. Cycles vitaux de quleques Plecopteres de Laurentides (insectes). Can. J. Zool. 47: 483-494. HARPER, P. J. C. PILON. 1971. Annual patterns of emergence of some Quebec stoneflies. Can. J. Zool. 48:681-694. HEIMAN, D. R. A. W. KNIGHT. 1975. The influence of bioenergetics of the carnivorous stonefly Acroneuria californica Banks (Plecoptera: Perlidae). Ecology 56: 105-I 16. H UBBS, C. L. A. PERLMUTTER. 1942. Biometric comparison of several samples, with particular reference to racial investigations. Amer. Natur. 76: 582-592. ILLIES, J. Katalog der rezenten Plecoptera. Das Tierreich, Berlin, 82: I-XXX: 1-632 pp. Growth maturity of the springtail, Gomphiocephalus hodgsoni Carpenter, from South Victoria Ross Isl, p. 295-305 in Entomology of Antarctica. Antarct. Res. Set. 10. Food habits dietary overlap of perlid stoneflies (Plecoptera) in a tributary of Lake Ontario, NY, USA. Can. J. Zool. 59: 2030-2037. JANETSCHEK, H. JOHNSON, J. H. KONDRATIEFF, B. C. J. I. DESPINS. Seasonal flight patterns of Plecoptera from North Otter Creek, Virginia. Ent. News 94: 41-44. MINGO, T. An annotated checklist of the stoneflies (Plecoptera) of Maine. Ent. News 94: 65-72. Plecopteros. in: Neuropteros neuvoso poco conocides. Mem. R. Acad. Cienc. Artes Barcelona. 14:5-13 (341-349). NAVAS, L. PECKARSKY, B. L. 1979. A review of the distribution, ecology evolution of North American species of Acroneuria six related genera (Plecoptera: Perlidae). J. Kans. Entomol. Soc. 52: 787-809. PETTRY, D. K. 1983. Ecological life history of Baetisca carolina Traver in Panther Creek, Nicholas County, West Virginia (Ephemeroptera: Baetiscidae). Unpublsh. Masters Thesis. Marshall University. 85 pp. REGER, D. B. 1921. West Virginia Geological Survey. County reports, Nicholas County. Wheeling News Lithographing Co., Wheeling, West Virginia. 847 pP. RICKER, W. E. 1935. Descriptions of three new Canadian perlids. Can. Ent. 67: 197-201. ROSENBERG, D. B., ED. 1979. Freshwater benthic invertebrate life histories: Current research future needs. J. Fish. Res. Bd. Can. 36: 289-345. SHELDON, A. L. 1969. Size relationships of Acroneuria californica its prey. Hydrobiologica 34: 85-94. SIEGFRIED, C. A. A. W. KNIGHT. 1976a. Prey selection by a setipalpian stone fly nymph Acroneuria (Calineuria) californica Banks (Plecoptera: Perlidae). Ecology 57: 603-608. 1976b. Trophic relations of Acroneuria (Calineuria) california (Plecoptera: Perlidae) in a Sierra foothill stream. Environ. Entomol. 5:575-581. 1978. Aspects of the life history growth of Acroneuria (Calineuria) californica in a Sierra foothill stream. Ann. Entomol. Soc. Am. 71: 149-154. STARK, B. P. A. R. GAUFIN. 1976. The Nearctic species of Acroneuria (Plecoptera: Perlidae). J. Kans. Ent. Soc. 49: 221-253. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png

Life History and Ecology of Acroneuria Carolinensis (Banks) in Panther Creek, Nicholas County, West Virginia (Plecoptera: Perlidae)

Feb 26, 2008
Free
14 pages

Loading next page...
/lp/hindawi-publishing-corporation/life-history-and-ecology-of-acroneuria-carolinensis-banks-in-panther-z0Ey2setBt
Publisher
Hindawi Publishing Corporation
Copyright
This article is in the public domain.
Publisher site
See Article on Publisher Site

Abstract

BY D. A. SCHMIDT D. C. TARTER Department of Biological Sciences Marshall University Huntington, WV 25701 INTRODUCTION Life history information is important to sampling techniques taxonomy, production, feeding, bioassay, environmental disturbance management studies. There is a basic lack of life history information that is needed by researchers resource managers (Rosenberg, 1979). Stoneflies are an important part of the stream ecosystem are useful as water quality indicators. Few studies concerning the life histories of Acroneuria spp. have been carried out. Siegfried Knight (1978) studied the life history of Acroneuria (Calineuria) californica Banks. Most other ecological data has been limited to A. abnormis A. lycorias concentrates on specific areas such as food habits, drift predator-prey relations. The objective of this investigation was to describe the life history of Acroneuria carolinensis with specific reference to: l) naiad age growth, 2) sex ratio, 3) food preference 4) emergence. TAXONOMY DISTRIBUTION Illies (1966) presented a review of the taxonomic changes of A croneuria carolinensis. A croneuria carolinensis was first described as a new species by Banks (1905) as Perla carolinensis from Black Mountain, North Carolina. In 1918, Navas placed it in another genus calling the insect Nostura carolinensis. Ricker (1935) assigned new nomenclature designated the insect as A croneuria custae. Claassen (1940) restored the specific name thus recognizing Acroneuria carolinensis as valid. *Manuscript received by the editor August 5, 1985 A croneuria carolinensis has been recorded from 11 states three Canadian provinces. It ranges from Manitoba, Ontario Quebec in southern Canada to Tennessee South Carolina in the United States (Peckarsky, 1979). MATERIALS METHODS Panther Creek originates in Nicholas County, 31/2 miles (5.6 km) southeast of the Greenbrier County line, near Saxman, West Virginia at an elevation of 3000 feet (914 m). Panther Creek flows northward, emptying into the Gauley River at an elevation of 820 feet (250 m); it has a total fall of 1180 feet. (360 m) a total length of 9.6 miles (15.4 km). The drainage basin area is 16.88 square miles (43.7 m2) (Reger, 1921). The study area is located along Route 39, 13.7 miles (22.1 km) west of the junction of Routes 19 39 at Summersville, at an elevation of 2200 feet (671 m). Collections were made in a riffle area 161 feet (49 m) below a concrete dam. The riffle was 36 feet (11 m) long had an average width of 25.6 feet (7.8 m). Substrate consists of rocks with an approximate size range of 6 to 18 inches (15 to 46 cm) in diameter. Qualitative samples were collected monthly from December 1984 to November 1985. After disturbing the substrate, a fine meshed dredge (mesh size: 4 mm, December-May; mm, June-November) was held immediately below the disturbed area to collect the drifting naiads. Contents of the dredge were emptied into a white enamel pan to facilitate sorting. Naiads were immediately killed preserved in 70 percent ethyl alcohol. Temperature of the stream was recorded monthly using a Fisher instantaneous thermometer. During the emergence period, temperature was recorded weekly. Water chemistry was measured monthly using a Hach chemical kit (Model AL-36B). Dissolved oxygen, carbon dioxide, hardness, alkalinity pH were measured in the field. All variables were measured in mg/1 except for pH. Total length (excluding antennae cerci) was measured by placing the naiad on a plastic millimeter ruler viewing under a binocular dissecting scope. Naiads were measured to the nearest 0.5 mm placed in mm class intervals. Length-frequency histo- grams were produced for each month. Number of age classes was determined based on the distribution of the body length. Population range diagrams (Hubbs Perlmutter, 1942) were used to show monthly head width variations between males females. Early instar naiads too small to sex (usually < 6.0 mm) were excluded from the analysis. Head width was measured to the nearest 0.05 mm using an ocular micrometer in a binocular dissecting microscope. Head width was used as a size stard because it changes least during preservation (Britt, 1953). Monthly growth rates were calculated as a percent increase in mean head width from one month to the next for males females. An estimation of the number of instars was calculated using the Janetschek method (Janetschek, 1967). Head width frequency histograms were produced for all collections combined. A trend-line for population growth was then calculated using a gliding mean over five successive class frequencies at a time. Gliding means were then subtracted from the frequency for each size class. These periodic maxima minima were ploted positive peaks were counted to determine number of instars. Sex of naiads was determined by examining the posterior margin of the 8th abdominal sternite. A chi-square test was performed on 72 males 152 females. Deviation from the expected 1" sex ratio was tested at the 0.05 confidence level. Naiad food preference was determined by examining the contents of the foregut. Twelve foreguts were analyzed each month. After the foreguts were removed by dissection, contents of the foregut were gently scraped onto a glass slide examined under a binocular dissecting scope. Food items were sorted identified to the lowest taxonomic unit possible. Taxa, number of taxa per foregut number of foreguts with the item were recorded. The mean number of a particular taxon per foregut the percentage of foreguts in which that taxon occurred (percent frequency of occurrence) were calculated on a monthly seasonal basis. Using a Ward ultraviolet light trap (8 watts), an attempt was made to collect emerging adults at the study area. On 31 May 1984, the trap was set up from 10:00 to 12:00 p.m. During May June, the banks of Panther Creek were searched for exuviae to determine the emergence period. Distance of exuviae from the stream bank type of substrate on which they were found were recorded. Dec Jan Feb _. rch April ", May "’a-= 35ijun e0 301Aug 350 I Sept Oct Nov 2O Body Length, mm Figure 1. Length-frequency histograms showing monthly distribution of Acro- neuria carolinensis naiads. Schmidt & Tarter Acroneuria carolinensis Fecundity was determined by direct egg count. Eggs were dissected out from 19 adults. They were placed in a syracuse watch glass counted under a binocular dissecting scope. Regression analysis was used to determine the relationship between total body length number of eggs produced. A correlation coefficient (r) was calculated to determine the strength of the relationship. The diameter length of 125 eggs from five adults were measured using an ocular micrometer in a binocular dissecting scope. Eggs were measured to the nearest 0.01 mm. Average egg size was calculated. RESULTS DISCUSSION Stream environment. The mean water temperature at Panther Creek during the study period was 8.3 C. The temperature ranged from 0.0 in January to 16 C in June. During emergence studies, a high temperature of 17 C was recorded on 8 June 1984. Dissolved oxygen was high, ranging from 7 to 13 mg/1 (X 9.4 mg/1). Carbon dioxide ranged from 10 to 85 mg/1, with a mean of 61.5 mg/1. Alkalinity ranged from 0.0 to 102.6 mg/1 (X 29.9 mg/1) during 1982, according to Pettry (1983). Total hardness ranged from 34.2 to 224.9 mg/1 (X 122.8 mg/1). The pH had a mean value of 6.9 ranged from 6.3 to 7.2. Length-frequency histograms. Length-frequency analysis indicated a two-year life cycle (Figure 1). Body length ranged from 3.5 to 26.0 mm. The largest naiads were collected in February, April May. Larger naiads were absent following the 20 May collection, when emergence had occurred. There was approximately an 11 week egg development period before recruitment of the new age class. The smallest earliest naiads were first collected in late August. The existence of a 6 mm naiad in January suggested some evidence that a three-year life cycle’,may be possible. Absence of additional naiads of this size could have been due to the larger mesh size dredge used during the winter collections. Harper Magnin (1969) suggested three-year life cycles for A. abnormis A. lycorias. They also indicated that the number of naiads collected was too small to make a definite conclusion. Sheldon (1969) reported a life cycle of three years for Calineuria californica at an elevation of 2200 m. Heiman Knight (1975) Siegfried Knight (1978) both suggested a two-year life cycle at lower elevation for C. californica. Allen Tarter (1985) reported a two-year life cycle for Eccoptura’ xanthanes (formerly A. xanthanes). Growth. Population range diagrams (Figure 2) showed a wide range in head width. The largest female head width was 6.22 mm occurred in October. The largest male head width was 5.07 mm occurred in December. Females exhibited greater mean head widths than males (Figure 2). Males exhibited greatest growth in August (12%) October (17%). Growth of females was greatest in August (28%) January (13%). The smallest immatures were first collected in August had their greatest growth in October (21%). Following emergence there was a marked decrease in mean head width for males in July (26%) females in June (30%). The population showed a sharp decrease in mean head width in August (48%). This decrease coincided with the recruitment of a new age class. Calineuria californica exhibited its greatest growth in spring when the stoneflies were still small (Siegfried Knight, 1978). Growth declined with an increase in size. In this study C. californiea showed an egg diapause early instars were not collected until February. In laboratory growth studies with C. californica, the greatest growth occurred in the summer, while the least occurred in the winter (Heiman Knight, 1975). The Janetschek method (Janetschek, 1967) indicated that A. carolinensis naiads underwent 25 instars (Figure 3a 3c). A general growth trend using gliding means is shown in Figure 3b. Sex ratio. A chi-square test was applied to 72 male 152 female A. carolinensis naiads. A significant deviation from the expected 1-1 ratio was observed at the 0.05 confidence level. Foregut analysis. Of the 144 foreguts examined, 78 (54%) contained food items. The highest percentage of empty foreguts occurred in April (75%). On a seasonal basis the percent of empty foreguts never exceeded 50 percent. Acroneuria carolinensis naiads were carnivorous, with Diptera (X 6.4, %FO 19.4), plecopterans (X 1, %FO 15.9), ephemeropterans (X 1, %FO 12.5) trichopterans (X 1.3, %FO 5.5) as the most important food items. Diptera was represented by larval chironomid midges. Plecopterans found in the foregut included members from the famijies Capniidae, Leutridae, Nem- Schmidt & Tarter Acroneuria carolinensis ww ’qiplM poex ouridae, Taeniopteryidae Peflodidae. Ephemeropterans included representatives from the genera Ephemerella, Epeorus, Cloeon, Stenonema a member from the family Baetidae. Trichopterans included representatives of the genera Glossosoma, Hydropsyehe Cheumatopsyehe. Results of monthly foregut analysis are presented in Figure 4. Plecopterans ephemeropterans made up the principle components of the diet throughout the year. Dipterans became important in the winter summer, while trichopterans were most important in the summer. Naiads fed most during the winter months with an average of 5.0 food items/stonefly. They fed least during the spring fall with an average of 1.1 food items/stonefly each season. Siegfried Knight (1976a, 1976b) Sheldon (1969) reported dipterans, trichopterans ephemeropterans as the most important food items for C. californica. Sheldon (1969) found that ephemeropterans were a regular component of C. californica’s diet dipterans were important in the winter summer. Siegfried Knight (1976a) stated that dipterans were the most important consistent food item for C. californica. Siegfried Knight (1976b) found that C. californica naiads showed no preference for a particular prey would eat anything available. They also reported a significant correlation between gut diversity benthic diversity. Sheldon (1969) stated that food consumption was low in the summer. In a laboratory study, Heiman Knight (1975) found that C. californica had its greatest food consumption in the summer, with minimal feeding in the winter, at normal environmental temperatures. Johnson (1981) reported that dipterans trichopterans were the primary diet for A. abnormis. The diet was supplemented with ephemeropterans. Phoresy. Larvae of a chironomid midge were observed living phoretically with A croneuria carolinensis naiads. The midges occurred on the prothorax or just beneath the mesothoracic wing pad. The phoretic attachment occurred on nine of 241 (3.7%) naiads examined. Dosdall Mason (1981) reported the chironomid Nanocladius (Plecopteracoluthus) branchicolus living phoretically on A. lycorias. They reported varied percentages of the number of stoneflies bearing the chironomids. The percentages of phoretic cases ranged from 10-50 percent. Rearing emergence. The attempt to collect emerging adults on 31 May 1984 was unsuccessful. Exuviae were collected up to 4.6 lO 23, I’ 1’ 4.0 5,0 Head Width mrn Figure 3. Growth rates of Acroneuria carolinensis naiads from Panther Creek, Nicholas County, West Virginia, 1983-1984: a) frequency of size classes; b) trendline of the population, calculated by gliding means over five successive size-class frequencies at a time; c) periodicity of maximum frequency of size. m from the water surface. They were found clinging to s, rocks, rhododendron stems moss. Based on the number of exuviae collected (33), peak emergence was on 8 June 1984; emergence lasted three weeks. The first exuvium was collected on June the last on 16 June. Emergence peaked with a corresponding peak in Plecoptera 40 Ephemeroptera or_ 41Trichptera Diptera IMI IM1 Month OI Figure 4. Percentage frequency of food items in foreguts of Acroneuria caroli- nensis naiads each month. temperature (17 C) (Figure 5). Mingo (1983) reported A. carol# nensis to be in flight from 12 June to 3 August in Maine. Flight periods for other A croneuria spp. recorded by Mingo (1983) were: A. abnormis, 10 June to 14 July; A. arenosa, 30 June to 3 August; A. lycorias, 10 July. Kondratieff Despins (1983) reported the Schmidt & Tarter Acroneuria carolinensis following flight periods for Acroneuria sp. related genera from Virginia: A. arenosa, late June to early July; A. abnormis, throughout June; Eccoptura xanthanes, late May through mid-July. Allen Tarter (1985) reported E. xanthanes emerged from 11 June to 14 July in Kentucky. In a separate study, A. carolinensis naiads adults were to be collected at Panther Creek in the spring of 1985. On 25 May no final instar naiads were collected. On 2 June a single final instar naiad was found after two hours of sampling. These findings suggested that emergence had taken place in mid-May, three weeks earlier than 1984 emergence. The weather in April 1985 was unseasonably warm, perhaps induced early emergence. Harper Pilon (1971) studied the emergence of A. abnormis for three years (1958, 1959, 1966). They found little temperature difference between the emergence curves, but cooler temperatures in 1958 had delayed emergence for two weeks. Fecundity. Of the 19 adults examined, only seven contained mature eggs. Therefore, mature eggs immature eggs of comparable size were counted. Direct egg count resulted in a range of 10 to 800 eggs (X 239) per female. There was little correlation between body length number of eggs (r 0.56). Egg size. A croneuria carolinensis eggs were oval in shape. Mean length was 0.43 mm (range 0.38-0.48 mm), mean diameter was 0.33 mm (range 0.29-0.38 mm). Stark Gaufin (1976) provided electron micrographs of the eggs gave detailed descriptions. From the material examined by Stark Gaufin (1976), two types of ova were found. They suspect two closely related species are involved suggested additional studies of the complex. SUMMARY The life history ecology of A croneuria carolinensis from Panther Creek, Nicholas County, West Virginia were studied from December 1983 to November 1984. Length-frequency distribution indicated a two-year life cycle. The largest naiads (26.0 mm) were collected in February, April May. Females males exhibited greatest growth in August (28%) October (21%), respectively. Naiads underwent 25 instars. A chi-square test applied to 72 males 152 females showed a deviation (0.05 confidence level) from the expected 1"1 sex ratio. Naiads were carnivorous in their feeding E 10 :11 June Figure 5. Naiad exuviae collected during May June, 1984, showing yearly pattern of emergence of Acroneuria carolinensis. habits. Plecopterans (X 1, %FO 15.9) ephemeropterans (X 1, %FO 12.5) made up the principle components of the diet. Dipterans were important components in the winter summer, while trichopterans became important in the summer. A phoretic relationship between A. carolinensis naiads a chironomid midge was observed on 3.7 percent of the naiads examined. Emergence was between June 16 June; peak emergence occurred on 8 June 1984. Direct egg counts for adult females ranged from 10 to 800 eggs (X- 239) per female. There was littld correlation between body length number of eggs (r 0.56). Mean egg length was 0.43 mm (range 0.38-0.48) mean egg diameter was 0.33 mm (range 0.29-0.38). ACKNOWLEDGMENTS The authors are especially thankful to the following persons for help in this investigation: Dale Adkins, Dean Adkins, Allan Brant, Creda Jim Meadows, Amy Messinger, Brian Reeder Thomas Weaks. Special thanks to Vickie Crager for typing the manuscript. LITERATURE CITED ALLEN, B. L. D. C. TARTER. Life history ecology of Eccoptura xanthanes (Newman) (Plecoptera: Perlidae) from a small Kentucky stream. Proc. Ky. Acad. Sci. (IN PRESS) BANKS, N. Descriptions of new species of neuropterous insects from the Black Mountains, N. C. Am. Mus. Nat. Hist. Bul. 21: 215-218. BRITT, N. W. 1953. Differences between measurements of living preserved aquatic insects caused by injury preservatives. Ecology 34: 802-803. CLAASSEN, P. W. 1940. A catalogue of the Plecoptera of the world. Mem. Cornell Univ. Agric. Exp. Stn. 232: 1-235. DOSDALL, L. M. P. G. MASON. 1981. A chironomid (Nanocladius branchicolus: Diptera) phoretic on a stonefly (Acroneuria lycorias: Plecoptera) in Saskatchewan, Canada. Can. Entomol. 113: 141-148. HARPER, P. E. MAGNIN. 1969. Cycles vitaux de quleques Plecopteres de Laurentides (insectes). Can. J. Zool. 47: 483-494. HARPER, P. J. C. PILON. 1971. Annual patterns of emergence of some Quebec stoneflies. Can. J. Zool. 48:681-694. HEIMAN, D. R. A. W. KNIGHT. 1975. The influence of bioenergetics of the carnivorous stonefly Acroneuria californica Banks (Plecoptera: Perlidae). Ecology 56: 105-I 16. H UBBS, C. L. A. PERLMUTTER. 1942. Biometric comparison of several samples, with particular reference to racial investigations. Amer. Natur. 76: 582-592. ILLIES, J. Katalog der rezenten Plecoptera. Das Tierreich, Berlin, 82: I-XXX: 1-632 pp. Growth maturity of the springtail, Gomphiocephalus hodgsoni Carpenter, from South Victoria Ross Isl, p. 295-305 in Entomology of Antarctica. Antarct. Res. Set. 10. Food habits dietary overlap of perlid stoneflies (Plecoptera) in a tributary of Lake Ontario, NY, USA. Can. J. Zool. 59: 2030-2037. JANETSCHEK, H. JOHNSON, J. H. KONDRATIEFF, B. C. J. I. DESPINS. Seasonal flight patterns of Plecoptera from North Otter Creek, Virginia. Ent. News 94: 41-44. MINGO, T. An annotated checklist of the stoneflies (Plecoptera) of Maine. Ent. News 94: 65-72. Plecopteros. in: Neuropteros neuvoso poco conocides. Mem. R. Acad. Cienc. Artes Barcelona. 14:5-13 (341-349). NAVAS, L. PECKARSKY, B. L. 1979. A review of the distribution, ecology evolution of North American species of Acroneuria six related genera (Plecoptera: Perlidae). J. Kans. Entomol. Soc. 52: 787-809. PETTRY, D. K. 1983. Ecological life history of Baetisca carolina Traver in Panther Creek, Nicholas County, West Virginia (Ephemeroptera: Baetiscidae). Unpublsh. Masters Thesis. Marshall University. 85 pp. REGER, D. B. 1921. West Virginia Geological Survey. County reports, Nicholas County. Wheeling News Lithographing Co., Wheeling, West Virginia. 847 pP. RICKER, W. E. 1935. Descriptions of three new Canadian perlids. Can. Ent. 67: 197-201. ROSENBERG, D. B., ED. 1979. Freshwater benthic invertebrate life histories: Current research future needs. J. Fish. Res. Bd. Can. 36: 289-345. SHELDON, A. L. 1969. Size relationships of Acroneuria californica its prey. Hydrobiologica 34: 85-94. SIEGFRIED, C. A. A. W. KNIGHT. 1976a. Prey selection by a setipalpian stone fly nymph Acroneuria (Calineuria) californica Banks (Plecoptera: Perlidae). Ecology 57: 603-608. 1976b. Trophic relations of Acroneuria (Calineuria) california (Plecoptera: Perlidae) in a Sierra foothill stream. Environ. Entomol. 5:575-581. 1978. Aspects of the life history growth of Acroneuria (Calineuria) californica in a Sierra foothill stream. Ann. Entomol. Soc. Am. 71: 149-154. STARK, B. P. A. R. GAUFIN. 1976. The Nearctic species of Acroneuria (Plecoptera: Perlidae). J. Kans. Ent. Soc. 49: 221-253.

There are no references for this article.

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off