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Biology and Production of Net-Spinning Caddisflies (Hydropsychidae And Philopotamidae) in a Regulated Portion Of The Brazos River, Texas

Description: Four species of net-spinning caddisflies, Hydropsyche simulans Ross, Cheumatopsyche lasia Ross, Cheumatopsyche campyla Ross and Chimarra obscura (Walker) are common in the regulated portions of the Brazos River. Hydropsyche simulans spun capture nets with the largest meshdimensions; the two Cheumatopsyche species' nets had the next largest meshes, and Chimarra obscura spun nets with the smallest dimensions. Cheumatopsyche lasia and C. campyla constructed nets with similar sized meshes. The number of individuals m~2 and standing crop biomass were not significantly different among low, medium, and high velocities. Early hydropsychid instars fed on detritus while later instar H. simulans and C. campyla had larger proportions of animal material. Guts of later instar C. lasia individuals had a greater percentage of algae and diatoms.
Date: May 1984
Creator: Malas, Diane M. (Diane Mary)
Partner: UNT Libraries

Population Dynamics of Macrobenthos in a Regulated Stream 1970-71 and 1978

Description: Stability of the macrobenthic community in a regulated section of the Brazos River, Texas, was evaluated. Physicochemical data and information on spatial distribution of macrobenthos were collected. Populations of two invertebrate species, Isonychia sicca and Neoperla clymene, had been greatly reduced since 1970-71 and I. sicca had been practically eliminated from this section of the Brazos. Three other insect populations, Choroterpes mexicanus, Cheumatopsche campyla and Cheumatopsyche lasia, had more than doubled their numbers since the 1970-71 study. A physicochemical gradient existed in this regulated section of the Brazos but it appeared to have changed little in comparison of earlier chemical data. A gradation of the macrobenthic community was evident as distance from the dam increased,
Date: August 1981
Creator: Coulter, James D. (James Duard)
Partner: UNT Libraries

Spring Food Habits of Corydalus Cornutus L. in the Brazos River, Texas

Description: The objective of this study was to determine the kinds and numbers of food organisms consumed by Corydalus cornutus, and to investigate its periodicity of feeding during the spring months in the Brazos River, Palo Pinto County, Texas. A total of 468 larvae were collected at two-week intervals from February 29 to May 14, 1971. Larvae were taken at opportunity during three periods of the day, 6am.-12pm., 12pm.-6pm., and 6pm.-12am. A total of 23 different food items was observed in the 121 stomachs containing food. An expedient method of dissection of the digestive tract is included.
Date: August 1971
Creator: Friday, Gary P.
Partner: UNT Libraries

Descriptions, Life History and Case-Building Behavior of Culoptila cantha (Trichoptera: Glossosomatidae) in the Brazos River, Texas

Description: Larval, pupal and adult samples of Culoptila cantha, from a large riffle of the Brazos River in north-central Texas from January, 1995 to March, 1997, indicated a predominately trivoltine cycle during both years; the over-wintering generation spanned 6-7 months and warm-season generations spanned 2-3 months. Eggs, larvae of all instars, larval cases, case reconstruction progression and behavior, pupae, and adults are described.
Date: August 1997
Creator: Houghton, David Charles
Partner: UNT Libraries

Cyrtonaias tampicoensis, Specimen #155

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an oval shape; moderately thick shell; single looped beak sculpturing; pink internal coloring; reddish-brown external coloring; no external sculpturing. Collected in the Brazos basin. The specimen measures between 60 - 100 mm in length and was assessed to be very-recently dead when collected.
Date: April 27, 1975
Creator: Britton, Joseph
Partner: Elm Fork Natural Heritage Museum

The Vertical Stratification of the Macrobenthos in the Brazos River, Texas

Description: Quantification of stream macrobenthos populations has remained a perplexing problem in rivbrine ecology, despite numerous attempts at improvement. This is in part due to well documented variations in chemical and physical parameters locally and geographically, and resultant adapted macrobenthos populations. Southwood (1968) and Hynes (1970a) have reviewed the various sampling techniques developed'for the census of lotic macrobenthos populations. Needham and Usinger (1956), Chutter (1969), and others have pointed out the difficulty in obtaining adequate numbers of samples which will yield population estimates with desired statistical confidence, and still maintain some degree of sampling economy. Needham and Usinger (1956) and Gaufin et al. (1956) mentioned the "patchy" distribution of aquatic insect populations as the primary source of this difficulty. The concept of patchy distribution in insect populations was originally discussed by Andrewartha (1961). Attempts to improve confidence through improved sampling devices and techniques have led to development of numerous types of samplers. Cummins (1962) indicated that there were almost as many samplers as there were researchers.
Date: December 1973
Creator: Poole, Walton Charles
Partner: UNT Libraries

The Life History and Ecology of the Mayfly Neochoroterpes mexicanus Allen (Ephemeroptera: Leptophebiidae)

Description: The life history and ecology of Neochoroterpes mexicanus was studied from data collected September, 1971, to August, 1972, and January to December, 1973, in the Brazos River, Texas. Nymphal development, instar analysis, voltinism, standing crops, and production estimates were determined from the quantitative samples taken in 1971 and 1972. Aspects of the life history and food habits of 230 specimens were arrived at from qualitative samples and light box captures in 1973. Laboratory investigation in 1973 helped in establishing instar analysis, egg incubation and description, and first instar descriptions. Neochoroterpes mexicanus appeared to have three generations per year with brood overlap in the summer and fall. It displayed 16 and 19 instars for overwintering and combined summer generations respectively.
Date: August 1974
Creator: McClure, Richard G.
Partner: UNT Libraries

Life cycle and ecology of the Hydropsychidae (Trichoptera) of the Brazos River, Texas

Description: Populations of all stages of three species of Hydropsychidae, Hydropsyche simulans, Cheumatopsyche campyla, and Cheumatopsyche lasia were sampled fro September, 1971, to August, 1972, on the Brazos River in Palo Pinto County, Texas. Supplemental observations relating to emergence, mating and oviposition, and larvae food habits were continued to July, 1973. The purpose of this study was to elucidate the life cycles and ecology of this Hydropsychidae complex.
Date: December 1973
Creator: Rhame, Roy Eddie
Partner: UNT Libraries

Truncilla macrodon, Specimen #1508

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; white internal coloring; tan external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be relatively-recently dead when collected.
Date: unknown
Creator: Kennedy, W. M.
Partner: Elm Fork Natural Heritage Museum

Truncilla macrodon, Specimen #1509

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; white internal coloring; tan external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be recently dead when collected.
Date: unknown
Creator: Kennedy, W. M.
Partner: Elm Fork Natural Heritage Museum

Truncilla macrodon, Specimen #1488

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; white internal coloring; yellow external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be recently dead when collected.
Date: unknown
Partner: Elm Fork Natural Heritage Museum

Truncilla macrodon, Specimen #1474

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; white internal coloring; tan external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be long dead when collected.
Date: unknown
Creator: Drake, N. F.
Partner: Elm Fork Natural Heritage Museum

Truncilla macrodon, Specimen #1513

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; white internal coloring; tan external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be recently dead when collected.
Date: unknown
Creator: Cummings, W. F.
Partner: Elm Fork Natural Heritage Museum

Lampsilis teres, Specimen #275

Description: One preserved mussel specimen including the right valve only. The specimen exhibits an elliptical shape; moderately thick shell; white internal coloring; tan external coloring; no external sculpturing. Collected in the Brazos basin. The specimen measures between 100 - 120 mm in length and was assessed to be relatively-recently dead when collected.
Date: April 27, 1975
Creator: Britton, Joseph
Partner: Elm Fork Natural Heritage Museum

Amblema plicata, Specimen #137

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a quadrate shape; thick shell; single looped beak sculpturing; white internal coloring; black external coloring; external sculpturing in the form of ridges. Collected in the Brazos basin. The specimen measures between 60 - 100 mm in length and was assessed to be live when collected.
Date: September 25, 1979
Creator: Golightly, C. & Kosinski, Robert
Partner: Elm Fork Natural Heritage Museum

Amblema plicata, Specimen #138

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a quadrate shape; thick shell; single looped beak sculpturing; white internal coloring; brown external coloring; external sculpturing in the form of ridges. Collected in the Brazos basin. The specimen measures between 60 - 100 mm in length and was assessed to be live when collected.
Date: September 25, 1979
Creator: Golightly, C. & Kosinski, Robert
Partner: Elm Fork Natural Heritage Museum

Amblema plicata, Specimen #139

Description: One preserved mussel specimen including the left valve only. The specimen exhibits a quadrate shape; thick shell; single looped beak sculpturing; white internal coloring; brown external coloring; external sculpturing in the form of ridges. Collected in the Brazos basin. The specimen measures between 60 - 100 mm in length and was assessed to be live when collected.
Date: September 25, 1979
Creator: Golightly, C. & Kosinski, Robert
Partner: Elm Fork Natural Heritage Museum

Amblema plicata, Specimen #140

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a quadrate shape; thick shell; single looped beak sculpturing; white internal coloring; brown external coloring; external sculpturing in the form of ridges. Collected in the Brazos basin. The specimen measures between 60 - 100 mm in length and was assessed to be relatively-recently dead when collected.
Date: August 28, 1980
Creator: Golightly, C. & Moorhead, D.
Partner: Elm Fork Natural Heritage Museum

Amblema plicata, Specimen #141

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a quadrate shape; thick shell; single looped beak sculpturing; purplish-white internal coloring; brown external coloring; external sculpturing in the form of ridges. Collected in the Brazos basin. The specimen measures between 60 - 100 mm in length and was assessed to be recently dead when collected.
Date: August 28, 1980
Creator: Golightly, C. & Moorhead, D.
Partner: Elm Fork Natural Heritage Museum

Amblema plicata, Specimen #142

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a quadrate shape; thick shell; single looped beak sculpturing; white internal coloring; dark brown external coloring; external sculpturing in the form of ridges. Collected in the Brazos basin. The specimen measures between 60 - 100 mm in length and was assessed to be relatively-recently dead when collected.
Date: August 28, 1980
Creator: Golightly, C. & Moorhead, D.
Partner: Elm Fork Natural Heritage Museum

Quadrula houstonensis, Specimen #1434

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; white internal coloring; yellow external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be relatively-recently dead when collected.
Date: unknown
Creator: Kennedy, W. M.
Partner: Elm Fork Natural Heritage Museum

Quadrula houstonensis, Specimen #1435

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; white internal coloring; tan external coloring; external sculpturing in the form of pustules. The specimen measures between 0 - 60 mm in length and was assessed to be recently dead when collected.
Date: unknown
Creator: Kennedy, W. M.
Partner: Elm Fork Natural Heritage Museum

Leptodea fragilis, Specimen #463

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an oval shape; thin shell; double looped beak sculpturing; white internal coloring; tan external coloring; no external sculpturing. Collected in the Brazos basin. The specimen measures between 100 - 120 mm in length and was assessed to be long dead when collected.
Date: April 27, 1975
Creator: Britton, Joseph
Partner: Elm Fork Natural Heritage Museum