38
PARASITES OF THE CRICKE'.' FROG, ACRIS CREPITANS, OF DENTON COUUTY, TEXAS APPROVED: Ma j o fefisor Minor Professor Director of the Department Biology Dean 01 the Graduate School I
PARASITES OF THE CRICKE'.' FROG, ACRIS CREPITANS,
OF DENTON COUUTY, TEXAS
APPROVED:
Ma j o fefisor
Minor Professor
Director of the Department Biology
Dean 01 the Graduate School I
PARASITES OF THE CRICKET FROG, ACRIS CREPITANS,
OF DENTON COUNTY, TEXAS
THESIS
Presented to the Graduate Council of the
North Texas State University in Partial
Fulfillment of the Requirements
For the Degree of
MASTER OF ARTS
By
Edward F. Block IV, B. A.
Denton, Texas
August, 1968
TABLE OF CONTENTS
Page
LIST OF TABLES iv
•LIST OF ILLUSTRATIONS V
Chapter
I. INTRODUCTION 1
Review of the Literature Statement of the Problem
II. NATURAL HISTORY OF THE HOST 7
III. METHODS AND MATERIALS 9
Collection and Utilization of the Host Collection of Parasites Preservation Technizues
IV. RESULTS 17
V. DISCUSSION AND SUMMARY 21
Discussion Summary
BIBLIOGRAPHY 30
XXX
LIST OP TABLES
Table Page
I. Occurrence of Parasites According to Sex and Collection Site of Host Specimens 18
II. Frequency of Infection According to Collection Site 19
III. Frequency of Infection According to Sex and Collection Site of Host Specimens .20
xv
LIST OF ILLUSTRATIONS
Figure Page
1. Denton County General Highway Map with Collection Sites Indicated 10
v
CHAPTER 1
INTRODUCTION
Review of the Literature
The taxonomy of the genus Acris (Amphibia, Anura) has
been subject to controversy subsequent to publication of the
volume by Wright and Wright (15) concerning the natural his-
tory and taxonomy of North American frogs and toads in 1933.
However, today the taxonomic relationships of the genus are
generally recognized by herpetologists to be those expressed
in the field guide to reptiles and amphibians written by
Conant (1) and published in 1958. The distribution maps in
the field guide are an invaluable guide in helping to estab-
lish the ranges of the two recognized species A. crepitans
and A. gryllus. Denton County, Texas,is within the range of
A. crepitans.
Walton (12, 13, 14) has catalogued the parasites of the
genus Acris. The following were listed as parasites of A.
gryllus: Nematoda—Cosmocercoides dukae, Oswaldocruzia
leidyi, 0. minuta, Rhabdias ranae, and Thubunae leiolopismae;
Cestoda—-Cvlindrotaenia americana, Nematotaenia dispar, and
Ophiotaenia magna; Trema toda—BrachycoeHum salamandraey
Protozoa--Hexamita sp., Opalina virguioidea macronucleata,
0. v. magninucleata, Nyctotherus coraiformis, Retromonas
dobelli, Trichomonas augusta, and Trypanosoma grylli. The
following were listed as parasites of A. crepitans:
Nematoda—Physalopteran larvae; Protozoa—Opalina obtrigon-
oidea, Nyctotherus cordiformis, and Trichomonas augusta.
The locations of collection of host specimens were not given;
therefore the above data constitute information referrable
only to the genus Acris.
Trypanosoma grylli was described in 1944 by Nigrelli (8)
from cricket frogs collected in Florida which is within the
range of A. gryllus. All other host records which have been
found are referable to A. crepitans.
The type specimen of Cylindrotaenia americana was des-
cribed by Jewell (3) in 1916. The site of collection of host-
specimens of cricket frogs was Urbana, Illinois.
In 1929, Walton (10) described specimens of the new
species Rhabdias ranae as parasites of North American frogs.
Cricket frogs collected in Urbana, Illinois, were listed as
host specimens to this new species.
In his description of helminths parasitic in the amphi-
bia and reptilia of Houston, Texas, Harwood (2) in 1932 listed
Cvlindrotaenia americana and Thubunae leiolopismae as parasites'
.of cricket frogs.
Trowbridge and Hefley (9) published a preliminary study
on the parasitic fauna of Oklahoma anurans in 1933. Cricket
frogs were found to be parasitized by Opalina sp., Cylindro-
taenia americana, and Rhabdias ranae.
Kuntz (4) presented a paper to the Oklahoma Academy of
Science in December, 1940, concerning the metazoan parasites
of some Oklahoma anura. Specimens of A. crepitans were re-
ported to be host to two cestodes, four nematodes, and one
acarina. Since only the parasites were listed, there is no
way of knowing which species were found in A. crepitans.
In 1941, Morgan (6) reported that physalopteran larvae
were recovered from the stomach of host specimens of A.
crepitans.
The new species Oswaldocruzia minuta was described in
1941 by Walton (11). Terre Haute, Indiana, was given as the .
site of collection of host specimens of cricket frogs.
In 1956, Loomis (5) reported his results of the study
of chigger mites (Arthropoda, Acarina) of Kansas and surround-
ing states. In this publication, Loomis cited three different
species of Hannemania found infesting host specimens of cricket
frogs..
The latest publication dealing with parasites of A. crep-
itans was an article by Morrison (7) in 1967. He reported
the lungworm, Rhabdias ranae, and the mite Hannemania pene-
trans from cricket frogs in southern Oklahoma.
Statement of the Problem
The purpose of this study was threefold. The literature
concerning parasites of A. crepitans was to be brought up to
date. Contributions to the general body of knowledge per-
taining to the parasitic fauna of host specimens of A_. crepi-
tans and specifically those found in Denton County, Texas,
were to be made. Finally, specimens found parasitizing host
specimens of A. crepitans were to be preserved and classified.
CHAPTER BIBLIOGRAPHY
1. Conant, R., A Field Guide to Reptiles and Amphibians of the United States and Canada East of the 100th Meridian, Boston, Massachusetts, Houghton Mifflin Company, 1958.
2. Harwood, P. D., "The Helminths Parasitic in the Amphibia and Reptilia of Houston, Texas, and Vicinity," Proceed-ings of the U. S.. National Museum, LXXXI (January, 1932) .
3. Jewell, M. E., "Cylindrotaenia americana n. sp. Prom the Cricket Frog, " Journal of Parasitology, II,, (February, 1916) 181-192.
4. Kuntz, R. E., "The Metazoan Parasites of Some Oklahoma Anura," Proceedings of the Oklahoma Academy of Science, XXI (January, 1941), 33-34.
5. Loomis, R. B., "The Chigger Mites of Kansas (Acarina,. Thrombiculidae)," University of Kansas Science Bulletin XXXVII (June, 1956), 1195-1443.
6. Morgan, R. B., "A Summary of the Physalopterinae (Nematoda) of North America," Proceedings of the Helmintholoqical Society of Washington, VII (January, 1941), 28-30.
7. Morrison, E. 0., "Mite and Lungworm Infections in Acris crepitans From Southern Oklahoma," Texas Journal of Science. XIX (November, 1967), 328-329.
8. Nigrelli, R. F., "Trypanosomes from North American Amphib-ians, with a Description of Trypanosoma grylli Nigrelli (1944) from Acris gryllus (Le Conte)," Zoologica, XXX (September, 1945), 45-47.
9. Trowbridge, A. H., and H. M. Hefley, "Preliminary Studies on the Parasite Fauna of Oklahoma Anurans," Proceedings of the Oklahoma Academy of Science, XIV (January, 1933), 16-19.
10. Walton, A. C., "Studies on Some Nematodes of North American Frogs I," Journal of Parasitology, XV (June, 1929), 227-240.
11. , "Oswaldocruzia minuta n. sp, (Nematoda) from Acris gryllus," American Midland Naturalist, XXV (March, 1941) , 418-^419.
12 . , "Parasites of tha Br achy c epha 1 idae and of the Hylidae," Journal of Parasitology, XXXII Sect. 2 supplement (December, 1946), 19.
13 . , "The Parasites of Amphibia," Wildlife Disease, XXXIX (February, 1964).
14. , "The Parasites of Amphibia, continued," Wildlife Disease, XL (September, 1964).
15. Wright, A. H., and A. A. Wright, Handbook of Frogs and Toads of the United States and Canada, Ithaca, New York, Comstock Publishing Associates, 1949.
CHAPTER II
NATURAL HISTORY OF THE HOST
Cricket frogs are semi-terrestrial and littoral. They
are found along the edges of springs, streams, rivers, ponds,
lakes, and impoundments in shallow water usually with emer-
gent vegetation and/or shoreline cover (3). Cricket frogs
appear to be the most abundant amphibians encountered within
the area of this study. They can be readily found during
the spring, summer, fall, and some winter months in Texas.
During colder winter months specimens are less numerous due
to adverse climatic conditions.
The breeding period extends from February (4) to Sep-
tember (1) in Texas. Eggs are laid singly or in small masses,
and are not concealed under objects. Newly metamorphosed
frogs may be found early in May (4). Burkett (2) noted that
most cricket frogs do not survive to breed more than once.
Cricket frogs are an .important source of food for semi-
aquatic snakes. Many are thought to be consumed by fishes,
water birds, and other predators. Other pertinent information
concerning the natural history of cricket frogs is contained
in a volume by Wright and Wright (5).
8
CHAPTER BIBLIOGRAPHY
1. Blair, W. P., "Calling and Spawning Seasons in a Mixed Population of Anurans," Ecology, XLII (January, 1961) 106.
2. Burkett, Ray D., Unpublished notes, Department of Biology, Texas Women's University, Denton, Texas, 1965.
3. Conant, R., A Field Guide to Reptiles and Amphibians of the United States and Canada East of the 100th Meridian, Boston, Massachusetts, Houghton Mifflin Company, 1958.
4. Pyburn, W. F., "Size and Movements of a Local Population of Cricket Frogs," Texas Journal of Science, X (September, 1958), 337.
5. Wright, A. H. and A. A. Wright, Handbook of Frogs and Toads of the United States and Canada, Ithaca, New York, Cornstock Publishing Associates, 1949.
Q
CHAPTER III
MATERIALS AND METHODS
Collection and Utilization of the Host «
Host specimens of A. crepitans were collected by hand
from either of two locations, McMath's cattle pond and the
Dry Fork of Hickory Creek (Fig. 1).
McMath's cattle pond is approximately six miles south-
southeast of Denton near the Pilot Knolls Park area bordering
Garza-Little Elm Reservoir. This permanent pond is roughly
in the shape of an isoceles triangle measuring about one hun-
dred feet across the base and about 250 feet along the sides.
The site is within a runoff depression that emptied into
Hickory Creek before the dam was built. This location lies
within the Eastern Cross Timbers. The dominant plant is
Post Oak, Quereus stellata. The pond fringe is fairly clear
in most places but underbrush and forest surrounds the area.
Cricket frogs were collected at the water's edge.
Collections on the Dry Fork of Hickory Creek were made
about fifty yards above the bridge of Interstate Highway 35
West about a mile west of the southwestern corner of the city
10
m £
I .
IK
fh*t Fig. 1—Denton. County general highway map with collection
sites indicated. McMath's cattle pond'—0 and The Dry Fork of Hickory CrecK—X.
II
of Denton. The site is located in the eastern edge of the
Grand Prairie; however,a Fraxinus-Ulmus streamside forest
association immediately surrounds the collection site. The
Dry Fork of Hickory Creek is dry during the latter months of
summer and often in winter. Flow normally begins with the
winter rains, extending through spring and into the early
summer. Cricket frogs were collected at semi-permanent ponds
in the low parts of the creek bed and/or along the bank of
the flowing creek.
Host specimens were kept in a terrarium with fine smooth
gravel lining the bottom. A wet paper towe1 or petri dish
top filled with water was placed on the gravel to keep the
terrarium moist. The top of the terrarium was covered with
a sheet of glass. Fruit flies, Drosophila melanoqaster, were
provided for food.
Collection of Parasites
Parasites found in the cricket frogs were classed as
endoparasites. However, specimens of Hannemania sp. were
readily seen beneath the transparent epidermis of living
frogs. The remainder of the parasites were obtained by dis-
section.
12
Host frogs were killed by decapitation. A probe was
inserted into the vertebral canal and manipulated from side
to side to destroy spinal reflexes. A sagittal incision was
made through the abdominal wall and terminated at the femoral
juncture. The cricket frogs were then placed ventor up in a
petri dish top and further dissected. A physiological saline
solution was poured into the abdominal cavity until the petri
dish was filled. The host specimen was completely covered
with the solution, which tended to flush out parasites free
in the abdominal cavity. These parasites could be seen with
the unaided eye when the dish was placed on an illuminated
dark surface. If parasites were present, they were examined
with a binocular dissecting scope or collected for preserva-
tion and study.
Next, the sex of the host specimen was determined and
recorded. The male was recognized by its dark, compact pair
of testes and the female usually by its fleshy, diffuse, and
yellow colored pair of ovaries.
The peritoneum and mesenteries were examined with a
binocular dissecting scope to determine the presence of para-
sites. The gall bladder, liver, and lungs were grossly
examined for parasites. In a similar manner, the epithelium
of the pharynx was examined. The tissue of the small and
13
large .intestines are sufficiently transparent to allow a gross
examination for parasites lodged in the mucosa or lumen of the
tract. Nevertheless, the alimentary tract was removed and
dissected sequentially from stomach to large intestine.
Preservation Techniques
Parasites were preserved and stained by standard histo-
logical techniques with modifications described below. Several
texts describing histological techniques were employed,
(1, 2,, 3).
Protozoa.—Protozoans were fixed in Schaudinn's fixative.
Best results were obtained using the following method: A few
drops of protozoa suspended in a physiological saline solution
were smeared over the surface of a no. 1 coverslip. The cover-
slip was then placed on a hotplate regulated to 40°C. The
liquid was allowed to evaporate until a moist film remained.
A container filled with Schaudinn's fixative was also on the
hotplate. The coverslip was removed and floated on the sur-
face of the fixative, film side downward. After a few seconds
of fixation, the organisms on the coverslip were stained "with
Heidenhain's iron'hematoxylin and counterstained with eosin.
Specimens were cleared in beechwood creosote and coverslips
were mounted on slides with Permount.
14
Platyhelminthes.—Metacercarial and adult specimens of
digenetic trematodes were relaxed in moderately hot saline
solution and then fixed with hot A. F. A. (alcohol-formalin-
acetic acid).
Cercarial specimens were fixed and stained in the same
manner as the protozoan specimens. Metacercaria and adults
were stained with Delafield's hematoxylin followed by Gomori's
trichrome or stained with acetocarmine. In both cases the
individuals were bathed with the progressive solutions in a
watchglass. Those specimens stained with Delafield's hema-
toxylin-Gomori's trichrome were cleared in beechwood creosote,
and coverslips were mounted on slides with Permount. Those
specimens stained with acetocarmine were mounted on slides with
glycerine jelly.
Cestodes were relaxed in lukewarm water and then fixed in
hot A. F. A. Specimens were stained in Delafield's hematoxylin-
Gomori's trichrome, cleared in beechwood creosote, and mounted
on slides with Permount.
Nemathelminthes.—Nematodes were fixed in a hot 70 percent
EtOH-5 percent glycerine mixture. The specimens were then cleared
in lacto-phenol (4) and placed in glycerine. Slides of the spec-
imens were prepared using glycerine jelly as the mounting medium.
1 5
Arthropoda,—Mites were fixed and cleared in 70 percent
isopropanol. Specimens were then mounted on slides with gly-
cerine jelly.
16
CHAPTER BIBLIOGRAPHY
1. Davenport, H. A., Histological and Histochemical Techni-ques, Philadelphia, Pennsylvania, W. B. Saunders Company, 1960.
2. Galiger, A. E., and E. N. Kozloff, Essentials of Practical Microtechnique, Philadelphia, Pennsylvania, Lea and Febiger, 1964.
3. Humason, G. L., Animal Tissue Techniques, San Francisco, California, W. H. Freeman, 1962.
4. Meyer, M. C. and L. R. Penner, Laboratory Essentials of Parasitology, Dubuque, Iowa, William C. Brown Company, 1962.
17
CHAPTER IV
RESULTS
One hundred and fifty host specimens of the cricket frog,
Acris crepitans, from each of two locations were examined for
the presence of parasites. Sixty-one males and thirty-nine
females were taken from McMath's cattle pond while nineteen
males and thirty-one females were taken from the Dry Pork of
Hickory Creek. The sex of individuals taken from a collection
site was noted and parasites found within the host specimens
were recorded. The occurrence of parasites in relation to
the sex and collection site of host specimens is presented
in Table I. The parasites are listed phylogenetically and
the numbers of host specimens that were infected are listed
accordingly.
The frequencies of infection of host specimens in relation
to the site of collection are expressed as percentages in Table
II. The frequencies of infection of host specimens in relation
to the site of collection and sex of the host are given in
Table III. The parasites are listed phylogenetically and the
frequencies as percentages are listed in the appropriate columns,
18
TABLE I
OCCURRENCE OF PARASITES ACCORDING TO SEX AND COLLECTION SITE OF HOST SPECIMENS
McMath1s Dry Fork of Cattle Hickory Pond Creek
Parasites Male Female Male Female
Protozoa
Opalina cf. virquloidea 33 24 10 24 Nyctotherus cordiformis 40 28 10 21 Myxidium serotinum 2 2 3 10
Digenea
Unknown metacercaria 31 12 3 9 Metacercaria of Dasymetra
conferta 18 9 4 5
Cestoda
Cylindrotaenia americana 3 1 2 5
Nematoda
Rhabdias ranae adult forms 25 10 0 0 strongyloid larvae 34 21 2 9
Larval Spiruroidean 29 12 0 1 Stronqyloid.es sp. 14 8 1 0
Acarina
Hannemania eltoni 31 17 13 17
Number of hosts per sex 61 ' 39 19 31 Total Number of hosts 100 50
19
TABLE II
FREQUENCY OF INFECTION ACCORDING TO COLLECTION SITS
Parasites McMath1s Cattle
Pond (percent)
Dry Fork of Hickory Creek
(percent)
Protozoa
Opalina cf. virgulo.ldea Nyctotherus cordiforinis Myxidium serotinum
Digenea
Unknown metacercaria Metacercaria of Dasymetra
conferta
57 68
4
43
27
68 62 26
22
16
Cestoda
Cylindrotaenia americana 14
Nematoda
Rhabdias ranae adult forms strongyloid larvae
Stronqyloides sp. Larval Spiruroidean
35 55 41 23
0 21 2 2
Acarina
Hannemania eltoni 43 60
Total number of hosts 100 50
20
TABLE III
FREQUENCY OF INFECTION ACCORDING TO SEX AND COLLECTION SITE OF HOST SPECIMENS
McMath1s Dry Fork of Cattle Hickory Pond Creek
Parasites Male Female Male Female
Protozoa
Opalina cf. virquloidea 54 62 53 77 Nyctotherus cordiformis 67 72 53 68 Myxidium serotinum 3 5 16 32
Digenea
Unknown metacercaria 51 31 15 26 Metacercaria of Dasymetra
conferta 29 23 21 16
Cestoda
Cylindrotaenia americana 5 3 1 16
Nematoda
Rhabdias ranae adult forms 41 25 0 0 strongyloid larvae 56 54 10 29
Stronqyloides sp. 48 31 0 3 Larval Spiruroidean 23 20 5 0
Acarina
Ilannemania eltoni 51 43 68 55
Number of hosts per sex 61 39 19 31 Total number of hosts 100 50
21
CHAPTER IV
DISCUSSION AND SUMMARY
Discussion
Protozoa,—Opalinids are endocommensals mostly in the
large intestines of Salientia (3). The fact that opalinids
have a direct life cycle (8) reflects their high incidence
of occurrence (Table II). Wessenberg of San Francisco State
College, a noted protozoologist who is working with opalinids,
has stated through personal communication that the monograph
of Metcalf (5) does not offer much assistance in the taxonomy
of opalinids because Metcalf did not provide adequate cri-
teria for taxonomy; and that no one has had the inclination
to repeat his work. The identification of Opalina cf. virgu-
loidea is based upon comparison of prepared slides, with Metcalf's
descriptions and must remain tentative pending further sutdy.
Nyctotherus cordiformis is an endocommensal ciliate
found in the colon of amphibia and various invertebrates (3).
The life cycle of this ciliate is direct (5) and this reflects
the high frequency of infection of host specimens (Table II).
' The coelozoic myxosporidian Myxidium serotinum was found
in the gall bladder of host specimens of A. crepitans. This
22
constitutes a new host record. Kudo (3) gives a very good
account of the morphology and life history of this organism.
Since spores are released in the feces of predators of host
specimens and ingested by tadpoles, one would expect similar
frequencies of infection from sites of collection of the host
specimens. The obvious discrepancy (Table II) may be explained
by the fact that Mr. McMath, owner of the land on which the
cattle pond is situated, owns a female Doberman Pinscher that
kills sna'kes. No snake was ever encountered at this locality
while snakes were numerous at the Dry Fork collection site.
The presence of many predators would aid in the dispersal of
the protozoa. McMath's cattle pond is also a large body of
water, while the collections on the creek were made mostly when
the water was concentrated into small pools. This would con-
centrate the creek population of adult cricket frogs and
tadpoles and insure a greater incidence of infection.
Digenea.--Three types of metacercaria were found encysted
in the peritoneum and mesenteries of host specimens. Two were
smaller (150 ) than the third form (200 jj) . One of the
smaller forms was determined to be metacercaria of the order
Ech ino atorn a ta. The other smaller form did not display dis-
tinguishing ordinal characteristics. The larger metacercaria
are thought to be those of Dasymetra conferta.
23
Since young specimens of water snakes and most species
of garter snakes rely upon cricket frogs as a food item (7),
it was surmised that adult specimens of the metacercaria
could be obtained from them. An adult specimen of Natrix
erythrogaster transversa, taken from the Dry Fork of Hickory
Creek,was found to be parasitized by adult specimens of
Dasymetra conferta.
Byrd (1) worked out the life cycle of D. conferta. An
attempt was made during this study to discover the complete
life cycle of D. conferta in the area of study. Snails of
the genera Physa and Heliosoma were collected, isolated, and
checked for evidence of shedding of cercaria. Xiphidiocercaria
were found to be shed and samples were prepared for further
study, but morphological characteristics could not be ade-
quately distinguished for taxonomic purposes.
Two specimens of Thamnophis sauritus proximus were taken
from the Dry Fork of Hickory Creek site. These snakes were
fed as many specimens of cricket frogs as could be supplied
to them. One snake died soon after capture, but the reason
for its death could not be determined. After two months,
the other snake was sacrificed and its upper alimentary tract
was fo\md to be heavily parasitized by specimens of D. conferta.
24
Cestoda.—Specimens of Cylindrotaenia americana were
collected from host specimens in all stages of development from
recently evaginated cysticerci to mature proglottid budding
adults. There was insufficient data for comparison of fre-
quency of infection from the two collection sites.
Nematoda.—Adult specimens of Rhabdias rsnae were found
in the lungs of host specimens. Some host specimens also
contained eggs of the "tadpole stage" and first ecdysis rhab-
diform larvae in the large intestine. In some frogs, third
ecdysis strongyloid larvae were present in the coelora when
adults were present in the lungs. No adults were found in
host specimens at the collection site on the Dry Fork of
Hickory Creek, but no data are available to explain this
absence.
The only visibly debilitating parasites were the speci-
mens of Stronqyloides sp. Some hosts infected with Stronqy-
loides appeared dead after a few days in the terrarium.
Autopsy revealed that their hearts were still beating and
their duodenal mucosa parasitized. The gross observation of
the tissue showed a state of necrosis. Enlarged blood vessels
made the tissue appear reddened and some evidence of hemorrhag-
ing could be seen. Severity of the infection varied from host
to host.
25
These nematodes appear to be an undescribed species of
the genus Strongyloides. Four species are known but none from
North America (11). No males were found. This fact and other
observations place these nematodes in the order Rhabdiasidae,
family Strongyloididae, and genus Strongyloides.
The larval Spiruroideans were found encysted in a flat
coil in the mesenteries of host _ specimens. No nematodes were
taken from the snakes experimentally infected and more inves-
tigation is needed concerning these forms.
The results do not show why the frequencies of infection
should be so high for the McMath collecting site and so low
for the Hickory Creek collecting site (Table II). Perhaps the
life cycles have a better chance of completion at the McMath
site since the predation is assumed to be lessened.
Acarina.—Larval mites were frequently encysted between
the epidermis and dermis. Mites of the genus Hannemania are
exclusively parasitic on amphibians (10). Loomis (4) listed
three species of Hannemania from Kansas and surrounding states:
2,. eltoni, H. dunni, and H. multifemoralis n. sp. H. multi-
femoralis, Loomis, 1956, has subsequently been placed in
synonomy of H. heqener.i, Hyland, 1955, described from Florida
(2). Morrison (6) and Trowbridge and Hefley (9) have cited
II. penetrans. Ewing, 1931, as parasitic on Acris. Loomis
26
(personal communication) has stated that H. penetrans
is conspecific with H. clunni, Sambon, 1928. Thus the three
species of Hannemania that could be found in Denton County
are H. eltoni, H. dunni, and H. hegeneri. According to the
taxonomic criteria of Loomis, the cricket frocp in this study
are probably infected with H. eltoni.
Morrison stated (person communication) that he merely
cited the work of Trowbridge and Hefley (9) in his 1967 pub-
lication (6). Thus it cannot really be said which species of
Hannemania were found infecting cricket frogs in southern
Oklahoma at this time.
The frequency of infection of the mite was similar at
both sites of collection of host specimens.
Frequency of infection varies with the sex of the host
at each site (Table III). However, this variance is not
enough to comment upon at this time. More data need to be
accumulated.
Summary
A total of one hundred and fifty host specimens of
Acris crepitans collected from two locations were examined
for parasites. Ten different forms were found to be present
and consisted of the following: Protozoa—Opalina cf.
27
virguloidea, Nyctotherus cordifo.rmis/ and Myxidium serotinum;
Trematoda—two unknown metacercaria and metacercaria of
Dasymetra conferta; Cestoda—Cylindrotaenia americana?
Nematoda—Rhabdias ranae, Strongyloides sp., and a larval
Spiruroidsan; A.cari:aa-;-Hannemania eltoni.
The presence of the sporozoan Myxidium serotinum in the
gall bladder of cricket frogs appears to constitute a new
host record. The presence of the metacercaria of Dasymetra
conferta in host specimens may also constitute a new host
record. An undescribed species of the genus Strongyloides
was found parasitizing the duodenal mucosa of host specimens.
Larval Spiruroideans have not previously been listed as
parasites of the genus Acris.
Differences in the frequency of infection of the various
groups of organisms represented occur between the site of
collection of host specimens and between the sex of host
specimens of a particular collection site. Data presented
are not sufficient to explain such discrepancies.
28
CHAPTER BIBLIOGRAPHY
1. Byrd, E. E. and W. P. Maples, "Developmental Stages in the Digenea V. the Egg, Miracidium, and Brood Mass in Dasymetra conferta Nicoll, 1911 (Trematoda: Plagior-chiodea: Ochetosomatinae)," Parasitology, LIV (May, 1964), 295-312.
2. Hyland, L. E., Jr., "A New Species of Chigger Mite, Hannemania hegeneri (Acarina, Trorabiculidae)," Journal of Parasitology, XLII (April, 1956), 176-179.
3. Kudo, R. R., Protozoology, 2nd ed., Springfield, Illinois, Charles C. Thomas, 1966.
4. Loomis, R. B., "The Chigqer Mites of Kansas (Acarina, Trombiculidae) , " The tJniversity of Kansas Science Bulletin, XXXVII (June, 1956), 1195-1443.
5. Metcalf, M. M., "The Opalinid Ciliate Infusorians," United States National Museum, Bulletin 130 (March, 1923), 1-484. . ~
6. Morrison, E. O., "Mite and Lungworm Infections in Acris crepitans from Southern Oklahoma," The Texas Journal of Science, XIX (November, 1967), 328-329.
7. Raun, B. B., "A Guide to Texas Snakes," Texas Memorial Museum, Museum Notes No. 9, 1965.
8. Smyth, J. D., Introduction to Animal Parasitoloqy, Springfield, Illinois, Charles C. Thomas, 1962.
9. Trowbridge, A. H. and H. M. Hefley, "Preliminary Studies on the Parasitic Fauna of Oklahoma Anurans," Proceedings of the Oklahoma Academy of Science, XIV (January, 1933), 16-19. " ~ "
10. Wharton, G. W. and H. S. Fuller, "A Manual of the Chiggers," Memoirs of the En t onto logical Society of Washington, IV (January, 1952), 1-185.
29
11. Yamaguti, Satyu, Systerna HeIrointhum, Vol. Ill, Part I and Part II, New York, Interscience Publishers, Inc., 1961.
30
BIBLIOGRAPHY
Books
Conant, R., A Field Guide to Reptiles and Amphibians of the United States and Canada East of the 1.00th Meridian, ~ Boston, Massachusetts, Houghton Mifflin Company," 1958.
Davenport, H. A., Histological and Histochemical Techniques. Philadelphia, Pennsylvania, W. B. Saunders Company, 1960.
Galxger, A. E., and E. N. Kozloff, Essentials of Practical Microtechnique. Philadelphia, Pennsylvania, Lea and Febiger, 1964.
Humason, G. L., Animal Tissue Techniques. San Francisco, California, W. H. Freeman, 1962.
Kudo, R. R., Protozoology. 2nd ed., Springfield, Illinois, Charles C. Thomas, 1966.
Meyer, M. C., and L. R.. Penner, Laboratory Essentials of Parasitology, Dubuque, Iowa, William C. Brown Company, 1962.
Smyth, J. D., Introduction to Animal Parasitology. Springfield, Illinois, Charles C. Thomas, 1962.
Wright, A. H., and A. A. Wright, Handbook of Frogs and Toads of the United States and Canada, Ithaca, New York, Comstock Publishing Associates, 1949.
Yamaguti, Satyu, Systerna Helminthum, Vol. Ill, Part I and Part II, New York, Interscience Publishers, Inc., 1961.
31
Articles
Blair, W. R., "Calling and Spawning Seasons in a Mixed Popu-lation of Anurans," Ecology, XLII (January, 1961), 106.
Byrd, E. E., and W. P. Maples, "Developmental Stages in the Digenea V. the Egg, Miracidium, and Brood Mass in .Dasymetra conferta Nicoll, 1911 (Trematoda: Plagior-chiodea: Ochetosoraatinae)," Parasitology, LIV (May, 1964), 295-312.
Harwood, P. D., "The Helminths Parasitic in the Amphibia and Reptilia of Houston, Texas, and Vicinity," Proceedings of the United States National Museum, LXXXI (January, 1932), 1-71.
Hyland, L. E., Jr., "A New Species of Chigger Mite, Hannemania hegeneri (Acarina, Trombiculidae)," Journal of Parasito-logy, XLII (April, 1956), 176-179.
Jewell, M. E., "Cylindrotaenia americana n. sp. from the Cricket Frog," Journal of Parasitology, II (February, 1916), 181-192.
Kuntz, R. E., "The Metazoan Parasites of Some Oklahoma Anura," Proceedings of the Oklahoma Academy of Science, XXI (January, 1941), 33-34.
Loomis, R. B., "The Chigger Mites of Kansas (Acarina, Throm-biculidae)," University of Kansas Science Bulletin, XXXVII (June, 1956), 1195-1443.
Metcalf, M. M., "The Opalinid Ciliate Infusorians," United States National Museum, Bulletin 120 (March, 1923), 1-484.
Morgan, R. B., "A Summary of the Physalopterinae (Nematoda) of North America, " Proceedings of the HeIminthological-Society of Washington, VII (January, 1941), 28-30.
Morrison, E. O., "Mite and Lungworm Infections in Acris creiptans from Southern Oklahoma," Texas Journal of Science, XIX (November, 1967), 328-329.
32
Nigrelli, R. F., "Trypancso-.es from North American Amphib-ians, with a Description of Trypanosoma grylli Nigrelli (1944) from Acris gryllus (Le Conte)," Zooloqica, XXX (September, 1945), 45-47.
Pyburn, W. R., "Size and Movements of a Local Population of Cricket Frogs," Texas Journal of Science, X (September, 1958), 337.
Trowbridge, A. H. and H. M. Hefley, "Preliminary Studies on' the Parasitic Fauna of Oklahoma Anurans," Proceedings of. the Oklahoma Academy of Science, XIV (January, 1933) , 16-19.
Walton, A. C., "Studies on Some Nematodes of North American Frogs I," Journal of Parasitology, XV (June, 1929), 227-240.
, "Oswaldocruzia minuta n. sp. (Nematoda) from Acris gryllus," American Midland Naturalist, XXV (March, 1941), 418-419.
, "Parasites of the Brachycephalidae and of the Hylidae, " Joux-nal of Parasitology, XXXII Sect. 2 supple-ment (December, 1946), 19.
, "The Parasites of Amphibia," Wildlife Disease, XXXIX (February, 1964)
"The Parasites of Amphibia, continued," Wildlife Disease, XL (September, 1964).
Wharton, G. W. and H. S. Fuller, "A Manual of the Chiggers," Memoirs of the Entomological Society of Washington, IV (January, 1952), 1-185.
Publications of Learned Organizations
Raun, G. G., "A Guide to Texas Snakes," Texas Memorial Museum, Museum Notes No. 9, 1965.
33
Unpublished Materials
Burkett, R. D., unpublished notes, Department of Biology, Texas Women's University, Denton, Texas, 1965.
