Entries - Entry Category: Science and Technology

Ozark Pocket Gopher

aka: Geomys bursarius ozarkensis
The Ozark pocket gopher is a small mammal that belongs to the family Geomyidae (pocket gophers) and the order Rodentia (rodents). It is endemic to Arkansas, occurring in Izard County. The common name “pocket gopher” comes from the fur-lined cheek pouches that these animals use to carry food. Two species of pocket gophers live in Arkansas. Geomys bursarius can be found from southern Manitoba southward through the central plains of the United States toward Arkansas and Texas, with the subspecies G. b. ozarkensis found in the southwestern one-third of Izard County in Arkansas. Although a few individuals have been captured on the southern side of the White River in adjacent Stone County, no current population resides in any other county …

Paddlefish

aka: Spoonbill Catfish
Paddlefish belong to the family Polyodontidae and order Acipensiformes. There are six known species—four are extinct (three from western North America, one from China) and known only from fossil remains, while two extant species include the paddlefish (Polyodon spathula), which is native to the Mississippi River basin in the United States, and the gigantic critically endangered Chinese paddlefish (Psephurus gladius) endemic to the Yangtze River Basin in China, where they lived primarily in the broad-surfaced main stem rivers and shoal zones along the East China Sea. Paddlefish are basal Chondrostean ray-finned fish; they are archaic and have been referred to as “primitive fish” because they have evolved with few unique morphological changes since the earliest fossil records of the late …

Paragould Meteorite

Two, possibly three, huge rocks from outer space put the Arkansas town of Paragould (Greene County) into the history and science books early in 1930. What is now known as the Paragould Meteorite was, at that time, the largest meteorite to ever have been seen falling and then recovered. A belt of rocks known as the asteroid belt, left over from the formation of the solar system, orbits the sun mainly between the orbits of planets Mars and Jupiter. Due to the gravity of nearby Jupiter, some of these rocks can stray inward and cross Earth’s orbit, even striking it. At 4:08 a.m. on February 17, 1930, the orbit of one of these rocks crossed Earth’s orbit, and two fields …

Parasitic Crustaceans

The Subphylum Crustacea (Phylum Arthropoda) represents a diverse group of animals with members within several classes and orders, including the Amphipoda, Branchiura, Cirripedia, Copepoda, Isopoda, and Tantulocarida. (The Pentastomida, composed of parasites, are sometimes included in this subphylum and sometimes considered a separate phylum.) There are two classes with parasites: the Maxillopoda and Malacostraca. The majority of crustaceans are aquatic, living in either marine environments or fresh water, but a few groups have adapted to a terrestrial existence, such as some species of crabs and woodlice. Most crustaceans move about independently and live a free existence, although some are parasitic (about 30,000 named species) and live attached as ectoparasites to their hosts, including fish, sea, and whale lice, as well …

Passenger Pigeons

aka: Ectopistes migratorius
The passenger pigeon (Ectopistes migratorius) was a North American bird species in the order Columbiformes (pigeons and doves) that became extinct in the early twentieth century. The fate of the passenger pigeon serves as a graphic lesson in the misuse of natural resources, as the species went from an almost indescribable abundance to extinction in only a few decades. The decline came primarily as a result of relentless persecution of its breeding colonies by market hunters, largely for meat, with no (or ineffectual) regulation that might have maintained a stable population. The passenger pigeon had the same general body shape as the common and familiar mourning dove (Zenaida macroura) but was larger and somewhat more colorful, with areas of slate-blue …

Pauropoda

Pauropods belong to the Phylum Arthropoda, Subphylum Labiata, Superclass Myriapoda, and Class Pauropoda. They are small, pale, millipede-like arthropods. There are about 830 species in twelve families worldwide, and they live under rocks in moist soil, leaf mold, and woodland litter. Only a single species, Eurypauropus spinosus, has been reported from Arkansas, but there are likely more that would be uncovered with further research. The only known fossil pauropod is Eopauropus balticus, a prehistoric species known from mid-Eocene Baltic amber (40 to 35 million years ago). Because pauropods are normally soil-dwelling, their presence in amber (fossilized tree sap) is unusual, and they are the rarest known animals in Baltic amber. They appear to be an old group closely related to …

Pentastomes

aka: Tongue Worms
The phylum Pentastomida (some consider it a class) includes four orders, seven families, and about 144 species, including eight extinct species from the Paleozoic Era. They are wormlike obligate parasites, meaning that they cannot complete their life cycle without a host. As adults, they inhabit the respiratory tract (lungs and nasal passages) of vertebrates. Four species are known from intermediate host insects (three coprophagus cockroaches and one coleopteran). In addition, fishes are common intermediate hosts for pentastomes occurring in crocodilians and piscivorous chelonians, and rarely for some species of snakes. Definitive hosts include amphibians (few hosts) but mainly reptiles (lizards, snakes, freshwater turtles, and crocodilians), the latter making up about seventy percent of hosts. The most common genera of reptilian …

Percidae

The Percidae is a family containing three subfamilies and approximately 250 species within eleven genera of perciform fishes found mostly in freshwater and brackish waters of the Northern Hemisphere. Most are found in the Nearctic realm. It is one of the largest families in North America, making up about one-fifth of all fish biota, only outnumbered by the Cyprinidae. There are also some Palearctic (Eurasian) species in the genera Gymnocephalus (four species), Percarina (two species), Romanichthys (single species), and Zingel (four species). The family includes the perches and their relatives, with some well-known species such as the ruffe, sauger, walleye, and three species of perch. However, much smaller fishes restricted to North America known as darters are also an integral …

Pillstrom Tongs

Pillstrom Tongs were invented by Lawrence G. Pillstrom MD for the safe capture of snakes for scientific research. The company eventually began shipping these unique, safe herpetological tools all over the world. They are used by zoos, animal control agencies, specialty animal handlers, collectors, and others. The company expanded upon the line of original snake tongs and modified them to be used for hunting frogs, pruning trees, cooking outdoors, picking up aluminum cans, and more. In 1953, as a young student at what is now the University of Arkansas for Medical Sciences (UAMS) in Little Rock (Pulaski County), Pillstrom began some early studies and medical research of snake venom and its effects. As a key part of his doctoral work, …

Pirate Perch

The pirate perch (Aphredoderus sayanus) belongs to the order Aphredoderiformes (or by some sources, Percopsiformes) and family Aphredoderidae. There are two subspecies, A. s. sayanus and A. s. gibbosus. It is the only living member of the family and ranges from the Atlantic and Gulf slopes from Michigan, Wisconsin, Minnesota, and New York south to the Gulf of Mexico and west to the Brazos River drainage, Texas. In Arkansas, A. sayanus occurs throughout the Coastal Plain physiographic region extending westward into the central areas of the state. It is quite rare in the Ozark uplands, and there are no records from the northwestern part of the state. The Aphredoderidae contains one fossil genus, Trichophanes, with possibly two of three valid …

Pittman, Margaret

Margaret Pittman was known worldwide for her pioneering research into the microbiology and immunology of infectious diseases. Her work in developing a vaccine for whooping cough remains the scientific basis (with later improvements) for protecting the children of Arkansas and the world from this potentially deadly disease. Margaret Pittman was born near Prairie Grove (Washington County) on January 20, 1901, to James Pittman, a country doctor, and Virginia Alice McCormick. In 1909, the family moved to the village of Cincinnati (Washington County), where Margaret and her sister sometimes helped with administering anesthesia and vaccinating patients in their father’s practice. After his early death, Virginia Pittman took her children—Margaret, Mary Helen, and James—to Conway (Faulkner County), where she did dressmaking and …

Planarians

aka: Triclads
There are at least seven species of planarians found in Arkansas, on land and in water. Planarians belong to the superphylum Lophotrochozoa, phylum Platyhelminthes, subphylum Catenulidea, class Rhabditophora (some consider the artificial grouping Turbellaria), order Tricladida, suborder Paludicola, and families Dugesiidae, Kenkiidae, Planariidae, and Dendrocoelidae. These flatworms are often simply referred to as triclads or triclad worms. Currently, the order Tricladida is split into three suborders, including the marine forms (Maricola); those found mostly in freshwater habitats of caves, although at least one species occurs in surface waters (Cavernicola); and land planarians/freshwater triclads (Continenticola). Scientists have argued about the systematics of platyhelminths for many years, and with the advent of molecular approaches (18S and 28S ribosomal DNA sequences), older classification …

Pro-ISIL Hack of Arkansas Library Association

In 2016, a pro-ISIL group hacked the website of the Arkansas Library Association (ArLA) and released the membership directory to other ISIL supporters as a scare tactic, although the breach had few consequences for the organization. In June 2014, the terrorist organization known as the Islamic State of Iraq and the Levant (ISIL), also called Islamic State (IS) or the Islamic State of Iraq and al-Sham (ISIS), declared a global caliphate (Islamic state ruled by a religious leader). By March 2015, ISIL had established its rule over sizeable portions of Syria and Iraq and benefitted from sympathetic supporters around the world. Starting in 2015, pro-ISIL supporters began waging indiscriminate cyberattacks against various Western websites and databases. Hackers specifically targeted websites …

Proturans

aka: Coneheads
Proturans belong to the Phylum Euarthropoda, Class Entognatha, and Class Protura. The Protura constitute a taxon of hexapods that were previously thought to be insects and now are considered as a class on their own. Proturans are cosmopolitan in distribution (except for both polar regions and snow zones of mountains) with more than 800 described species belonging to three distinct orders (Acerentomata, Eosentomata, and Sinentomata) and seven families (Acerentomidae, Antelientomidae Eosentomidae, Fujientomidae, Hesperentomidae, Protentomidae, and Sinentomidae). As of 2019, seventy-six genera are known worldwide, with nearly 300 species contained within the single cosmopolitan genus, Eosentomon. There are about twenty-six species in North America, though there is no exact number of species reported, to date, from Arkansas. However, four species of …

Purdue, Albert Homer

Albert Homer Purdue was the ex officio state geologist from 1907 to 1912. He published many works on the geology of both Arkansas and Tennessee. Purdue was a renowned geologist and taught at Arkansas Industrial University, which is now the University of Arkansas (UA) in Fayetteville. Albert Purdue was born on March 29, 1861, on a farm near Yankeetown, Indiana, to Samuel Leroy and Phoebe (Priest) Purdue. Albert was the second oldest of eight children and spent his youth working on the family farm, receiving only minimal formal education. At the age of twenty, however, he entered the Indiana State Normal School (later Indiana State University) in Terre Haute. He received his diploma on June 8, 1888. Until 1896, Purdue …

Ranavirus

Ranaviruses are viral pathogens (double-stranded DNA viruses) that infect a broad diversity of at least 175 ectothermic (cold-blooded) vertebrates across the globe; they belong in the genus Ranavirus (RV) of the family Iridoviridae. The genus is composed of six recognized viral species, three of which—tiger salamander (Ambystoma tigrinum) virus (ATV), Bohle iridovirus (BIV), and the type species, frog virus 3 (FV3)—are known to infect amphibians. There are four additional genera of viruses within this family, but RV is the only one that includes viruses that are infectious not only to amphibians but also reptiles and wild and cultured teleost fishes. A study in 2016 found no occurrence of ranavirus in Arkansas in turtles of the eastern part of the state …

Razorback Hogs

Arkansas was known for its razorback hogs long before the University of Arkansas mascot came into being. These wild boars were called razorbacks because of their high, hair-covered backbone and ill-mannered temper. The razorback hog was considered ruthless and dangerous when backed into a corner. The true wild boar, also called the European or Russian boar, is not native to the United States. Christopher Columbus introduced their domesticated ancestors to the New World in 1493. Wild boars are thought to have arrived with explorer Hernando de Soto, who brought the original thirteen grunting hogs to the new world in 1539, though this theory has lately been cast into doubt by Charles Hudson, who reconstructs de Soto’s path in his book, …

Red-cockaded Woodpeckers

aka: Picoides borealis
With the exception of the recently rediscovered ivory-billed woodpecker, red-cockaded woodpeckers (Picoides borealis) are the rarest of Arkansas’s nesting woodpeckers. A century ago, the bird was common in mature, open pine stands. Its natural range included millions of acres of pine habitat throughout the southeast United States. An estimated ninety-nine percent of suitable habitat was lost because of logging, wildfire suppression, conversion to agricultural lands, and urbanization. Best estimates range-wide indicate an original population numbering over four million. By the time the bird was declared endangered, it had declined to an estimated 10,000. The Arkansas population dwindled to under 400 birds. The red-cockaded woodpecker was designated as endangered on October 13, 1970. It received formal legal protection with the passage …

Remmel Dam

aka: Lake Catherine
Remmel Dam is situated on the Ouachita River at Jones Mills (Hot Spring County). It was constructed in 1924 by Arkansas Power and Light (AP&L), now Entergy, in response to the growing demand for electrical power in southern Arkansas and surrounding states. The dam impounds Lake Catherine and, together with Carpenter Dam in Hot Springs (Garland County), provides hydroelectric power for southern Arkansas. Part of a three-dam project on the Ouachita River along with Carpenter Dam (completed in 1931) and Blakely Mountain Dam (completed in 1953), it played an important role in the early development of AP&L. In 1916, former riverboat captain Flave Carpenter met with Harvey Couch, who founded AP&L in 1913, to discuss the possibility of building dams on …

Reptiles

Arkansas’s reptilian biodiversity includes four groups—turtles, lizards, snakes, and the American alligator—each with a sharply different body morphology. By closely examining the morphology of these varied groups within the class Reptilia, today’s phylogenetic taxonomists (individuals who study the evolutionary relationships among species) have found that members of this class share several recently derived features (such as skull characteristics) with birds. Because of this modern understanding of the evolutionary relationships among reptilian ancestors and their descendents, which include dinosaurs and birds, some taxonomists have proposed a new class (Eureptilia) to include dinosaurs, birds, crocodylians, all of their close diapsid relatives (including lizards and snakes), and a number of extinct groups. However, the classical taxonomic designation for the class Reptilia includes turtles, …

Riddle’s Elephant and Wildlife Sanctuary

Opened in 1990 by Scott and Heidi Riddle, Riddle’s Elephant and Wildlife Sanctuary, located on 330 acres outside of Greenbrier (Faulkner County), provides a permanent home for African and Asian elephants in need of sanctuary for any reason, regardless of age, sex, species, health, or temperament. Elephants come from private owners, circuses, or zoos. The 501(c)(3) nonprofit sanctuary—which raises money through grants and donations—houses up to a dozen elephants at any given time, with three baby elephants born at the facility as of 2010. Maximus, an African elephant born at the sanctuary in 2003, starred in Animal Planet’s television show Growing Up Elephant. Scott and Heidi Riddle met while both were working at the Los Angeles Zoo, and they married …

Rivervale Inverted Siphons

Completed in 1926, the Rivervale Inverted Siphons were a prerequisite to permanent settlement in eastern Poinsett County and adjacent areas in the St. Francis River and Little River basins. The siphons provided relief from overflow and outlet for runoff from Craighead and Mississippi counties and portions of southeastern Missouri. One of the first components in the comprehensive drainage plan devised for Drainage District Number Seven of Poinsett County, the Rivervale Inverted Siphons also permitted the immediate agricultural development and economic exploitation of parts of Poinsett County and those counties in Missouri and Arkansas tributary to District Seven. They were also a necessary response to the proliferation of organized drainage and levee districts in the early twentieth century. The siphons were …

Rock Island Bridge (Little Rock–North Little Rock)

aka: Choctaw Bridge
aka: Clinton Presidential Park Bridge
The Rock Island Bridge is a lift-span bridge crossing the Arkansas River between downtown Little Rock (Pulaski County) and North Little Rock (Pulaski County). One of six bridges linking the two downtowns, the Rock Island Bridge was originally constructed as a railroad bridge in 1899; it was converted to serve as a pedestrian bridge in 2011 to complement the William J. Clinton Presidential Center and Park. In late 1898, the Choctaw and Memphis Railroad was organized with the goal of establishing a railroad into the Indian Territory (modern-day Oklahoma). Congress passed legislation authorizing construction of a new bridge across the Arkansas River in January 1899, and the Little Rock Bridge Company formed that May to develop plans for constructing the …

Rocks and Minerals

There are three basic classes of rocks: igneous, metamorphic, and sedimentary. Igneous rocks are those that solidified from magma (molten rock). Metamorphic rocks are formed from pre-existing rocks in a solid state by heat, pressure, and/or chemical activity. Sedimentary rocks are made up of particles of sediment cemented together. In Arkansas, the overwhelming majority of surface and near-surface rocks are sedimentary rocks. There are a few igneous rocks and some very low-grade metamorphic rocks, but these occupy little area. Out of Arkansas’s total area of 53,179 square miles, only about fifteen square miles are composed of igneous rocks. In the Ozark Plateau and Ouachita Mountains, there are indications of some very low-grade metamorphic effects on the rocks in restricted areas, …

Rotifers

aka: Wheel Animals
The Phylum Rotifera (“wheel animals”) contains over 2,100 nominal taxa of microscopic and near microscopic species of unsegmented, bilaterally symmetrical pseudocoelomate invertebrates. They were originally named in 1696 by Anglican priest John Harris (1666–1719) and studied in 1703 by Antoine van Leeuwenhoek (1632–1723). Several surveys of Rotiferans have been done in Arkansas, although there is no summation of the species as of 2019. Because they are minute and mostly composed of soft bodies, rotifers are not commonly supported for fossilization. Their only hard parts, their jaws, are sometimes preserved in the fossil record, but their size makes detection challenging. However, fossils of Habrotrocha angusticollis have been found in Pleistocene (2.5 million to 11,700 years ago) peat deposits of Ontario, Canada. …

Salmonids

aka: Trout
aka: Salmon
Salmonids include chars, graylings, salmon, trout, and freshwater whitefishes, all of which belong to the superorder Protacanthopterygii, order Salmoniformes, family Salmonidae, three lineages or subfamilies (Coregoninae, Thymallinae, and Salmoninae), eleven extant genera, and about 120 species. There are thirty-nine species known in North America. The family is widely distributed, with various species found north of the equator in Asia, Europe, and North America. Some important North American genera include Coregonus, Oncorhynchus, Prosopium, Salmo, Salvelinus, and Thymallus. Although no members are native to Arkansas, salmonids have been introduced, primarily for purposes of sports fishing. The family initially appears in the fossil record in the middle Eocene (48 to 38 million years ago) from fossils found in central British Columbia, Canada. A …

Schilberg, Richard

Richard Schilberg was an aviation pioneer whose early efforts in Stuttgart (Arkansas County) made him Arkansas’s first acknowledged aircraft manufacturer. Richard Schilberg was born on September 28, 1887, at Canada, Kansas, the son of Gottlieb Schilberg and Juliana Heidt Schilberg. He moved to Stuttgart in 1909 and opened a welding shop, initially specializing in agricultural machinery. He married Gladys Fricker on January 28, 1913. They divorced in 1926 and he married Mable Stilzen in 1927. The couple took their first airplane rides in June 1913, when one of Arkansas’s first aerial exhibitions came to the town. Increasingly interested in flying, he began building aircraft in Stuttgart by 1914, becoming the first major promoter of aviation in the Grand Prairie region. …

Science and Technology

Arkansas has had a rather conflicted relationship with science and technology throughout its history. On the one hand, the state existed for a long time on the American frontier, separated from the intellectual and academic centers of the rest of the nation; hence, its residents have been popularly perceived throughout history as possessing an anti-intellectual strain, an image on occasion reified during, for example, controversies regarding the place of evolutionary theory in public education. On the other hand, political leaders, and the people themselves, fairly readily support scientific research that promises to have an immediate economic benefit for the state of Arkansas. Given Arkansas’s place as a largely agricultural state, it is no surprise that much of this research has …

Scorpionflies

aka: Mecopterans
Scorpionflies belong to the Phylum Arthropoda, Class Insecta, Superorder Endopterygota, and Order Mecoptera. There are about 605 species within thirty-four genera and nine families worldwide. There are also 400 known fossil species in about eighty-seven genera, which are more diverse than even the extant members of the order. Sixteen species representing three families of scorpionflies occur in Arkansas. Most mecopterans live in moist environments, although adults of a few species are found in hotter semi-desert habitats and may be active and noticeable only for short intervals of the year. Those in the family Panorpidae generally inhabit broad-leaf woodlands with abundant damp leaf litter. Snow scorpionflies (family Boreidae) appear in winter and are often seen on snowfields and on moss; the …

Sculpins

aka: Cottids
Sculpins belong to the order Scorpaeniformes and superfamily Cottoidea. There are about 11 families, 149 genera, and 756 species. They reach their maximum diversity in the northern Pacific Ocean. The family Cottidae is the largest family, with approximately 258 species; the second-largest family is the Agonidae (marine poachers), with 47 species. The most speciose genus, Cottus (freshwater sculpins), is confined to North America and Eurasia. It includes about 68 taxa that are native to the Northern Hemisphere (Palearctic and Nearctic realms). There is fossil material similar to Cottus that dates to at least the Miocene Epoch (23 to 5.3 million years ago). Most sculpins are generally less than 15 centimeters (6 inches) in length, although a few species can reach …

Shrews

Shrews are very small, secretive, mouse-like mammals that inhabit moist, shady woodland areas. Generally, they have long, flexible, pointed snouts and very small eyes and ears. Their fur is soft and dense, and most species have prominent scent glands. All shrews belong to the Family Soricidae (subfamilies Soricinae, Crocidurinae, Myosoricinae) and Order Eulipotyphia, which also includes moles, shrew-like moles, desmans, gymnures, hedgehogs, and solenodons. True shrews, talpids, and solenodons were formerly grouped in the clade Soricomorpha; however, Soricomorpha has been found to be paraphyletic (descended from a common evolutionary ancestor or ancestral group, but not including all descendant groups). Members of this order are nearly cosmopolitan in distribution, with the exception of Australia, New Zealand, Antarctica, extreme southern South America, …

Shrimps

aka: Prawns
Arkansas shrimps belong in the cosmopolitan Family Palaemonidae (subfamily Palaemoninae) and Order Decapoda, which also contains the crayfishes. Taxonomically, shrimps are differentiated from crayfishes by their first pair of legs with chelae and the abdomen laterally compressed, while crayfishes have the first three pairs of legs with chelae and their abdomens dorsoventrally flattened. The Palaemonidae is a large family (950 species within 137 genera) and is distributed on all the continents except in the deep oceans, in temperate and tropical regions, and having representatives in marine, brackish, and fresh water. Representatives of this family are mainly carnivores that feed on small invertebrates. The most prominent genus in the family is Macrobrachium, with over 240 species that include commercially fished species; …

Shrubs

In 2016, a total of 436 kinds of woody plants were known to occur in the wild in Arkansas, comprising 419 species plus another seventeen varieties and subspecies. Of these, 185 can be considered trees, 189 are best described as shrubs, and sixty-two are woody vines. In some cases it is difficult to draw a hard line between these categories, and various references differ in their criteria for each. For the purposes of this entry, however, each category is defined as follows: Trees are defined as perennial, often single- or relatively few–stemmed woody plants typically greater than five meters (sixteen feet) in height at maturity. Shrubs are defined as perennial, often multi-stemmed woody or semi-woody plants usually less than five …

Silitch, Mary Frances

Mary Frances Files Silitch is the first woman to be editor-in-chief of a national aviation magazine. A licensed pilot, she has flown 250 kinds of aircraft and logged 5,000 hours of flight. Mary Frances Files was born on November 9, 1935, in Little Rock (Pulaski County) to William Thomas Files and Johnnie Caldwell Files of Parkdale (Ashley County); she has two sisters. Her first flight was in an open-cockpit crop-duster airplane over the family farm at the age of four. She attended schools in Parkdale and Wilmot (Ashley County) but graduated from All Saints Episcopal School in Vicksburg, Mississippi. She attended Southwestern at Memphis (now Rhodes College), where she began her journalism career as the managing editor of the Sou’wester, …

Silverfish

aka: Bristletails
Silverfish are small, wingless insects in the order Zygentoma (formerly Thysanura). There are four families: Lepidotrichidae (single species), Lepismatidae (about 200 species), Maindroniidae (three species), and Nicoletiidae (about twenty species). In the late twentieth century, it was recognized that the two suborders were not sister taxa; therefore Thysanura was paraphyletic, and the two suborders were each elevated to the status of an independent monophyletic order, with Archaeognatha the sister taxon to the Dicondylia, including the Zygentoma (fishmoths, firebrats, and silverfish). A nicoletiid, Speleonycta ozarkensis, occurs in eight different cave systems in Arkansas in Benton and Newton counties and in Oklahoma in Adair, Cherokee, and Delaware counties. In concert with jumping bristletails (Order Microcoryphia), the predecessors of silverfish are considered the …

Slime Molds

Slime molds are among the more interesting yet relatively little known organisms found in Arkansas. They do not have a particularly attractive name, but some examples produce fruiting bodies that are miniature objects of considerable beauty. The organisms commonly referred to as slime molds actually belong to two different taxonomic groups—the myxomycetes and the dictyostelids. Members of both groups are common-to-abundant organisms in forests throughout Arkansas, but only the myxomycetes (also called plasmodial slime molds) can be observed directly in nature. As a result, the myxomycetes are by far the better known group, and to most people (including many biologists), they are the only “slime molds” of which they are aware. However, the dictyostelids (also known as cellular slime molds) …

Smelts

aka: Osmerids
Smelts belong to the family Osmeridae and order Salmoniformes. There are seven genera and about eleven species. Fishes of the genus Osmerus, to which the rainbow smelt (O. mordax) belongs, include the following: a North Pacific and Arctic species, O. dentex; the European smelt (O. eperlanus) of the Eastern North Atlantic; and the landlocked pygmy smelt (O. spectrum) of eastern Canada and New England, which some authorities suggest is not a valid species. In general, smelts are north circumpolar in geographic distribution, and they occur in marine and freshwater habitats in Asia, Europe, and North America. They date to the Paleocene Epoch (over 55 million years ago). The closest relatives are galaxioid (Protacanthopterygiid) fishes, and the marine argentinoid fishes are …

Snake Fungal Disease

aka: Ophidiomycosis
Snake fungal disease (ophidiomycosis) is an emerging infectious disease of numerous species of snakes caused by the fungus Ophidiomyces ophiodiicola within the family Onygenacea. Formerly, Ophidiomyces was classified as the Chrysoporium anamorph of Nannizziopsis vriesii species complex (CANV species complex), a group of fungi that are frequently associated with emerging infections in various groups of reptiles. However, recent phylogenetic analyses have demonstrated that CANV represents a species complex that also includes fungi of the genera Nannizziopsis and Paranannizziopsis and that Ophidiomyces is known to occur only on both colubrid and viperid snakes. It was first definitively identified in 2006 in a population of timber rattlesnakes (Crotalus horridus) in New Hampshire. However, although identification has not been conclusively proven because cultures …

Southern Cavefish

aka: Typhlichthys subterraneus
The southern cavefish (Typhlichthys subterraneus) is one of the two species of blind cave fishes found in Arkansas. The other is the Ozark cavefish. The southern cavefish is found in the subterranean waters of two major non-overlapping ranges separated by the Mississippi River: in the Ozark Plateau of central and southeastern Missouri and northeastern Arkansas and in the Cumberland and Interior Low plateaus of northwest Alabama, northwest Georgia, central Tennessee, and Kentucky. They are usually found at considerable depths (mostly between 175 and 240 meters below the land surface). This species, which can grow as long as ninety millimeters, has a large, broad head. The caudal fin has from zero to two rows of sensory papillae (one on the upper …

Speckled Pocketbook

aka: Lampsilis streckeri
The speckled pocketbook is a bivalve mollusk belonging to the family Unionidae, commonly referred to as freshwater mussels, naiads, or clams. Each freshwater mussel is composed to two halves (valves) of a hard outer shell with the living animal (soft tissues) residing securely inside. The speckled pocketbook, scientific name Lampsilis streckeri, was described as a species new to science in 1927 by Lorraine Screven Frierson, a naturalist and landowner/merchant/planter residing south of Shreveport in the company town of Frierson, Louisiana. Frierson named the species in honor of his friend, colleague, and fellow naturalist John K. Strecker of Waco, Texas. Adults may reach a length of slightly more than 3.5 inches (or more than 90 millimeters), with a maximum life expectancy …

Sponges

The phylum Porifera, which contains the sponges, is a highly successful group of metazoan animals that includes about 8,600 living species of marine and freshwater forms as well as some that inhabit brackish waters. The majority are marine, but there are about 150 species of freshwater sponges, including twenty-seven to thirty species found in North America north of Mexico. The family Spongillidae is the most speciose and widespread group of freshwater sponges and includes twenty-two genera and more than 130 species from a wide variety of habitats. Seven species of freshwater sponges have been documented in Arkansas. Sponges are an ancient group of asymmetrical invertebrates with a fossil record preceding the early Cambrian period (541 million years ago), and even …

Stern’s Medlar

aka: Crataegus × Canescens
aka: Mespilus canescens
Stern’s medlar (Mespilus canescens or Crataegus × canescens) is a rare shrub in the rose family known in the wild from about twenty-five individual plants at a single site near Slovak (Prairie County). It was first discovered in 1969 by Jane Stern but was not named until 1990, when it was formally described (as Mespilus canescens) by Dr. James Phipps of the University of Western Ontario. Its origin, taxonomic placement, and proper scientific name are a matter of debate among botanists and represent one of the most curious and persistent mysteries in North American botany. Stern’s medlar is a showy species with a number of desirable ornamental properties including dense groupings of quarter-sized white flowers, multiple trunks, arching branches, patchy …

Stobaugh, Robert Blair

Robert Blair Stobaugh was an authority on energy, international business, and corporate governance who served as a professor in the Harvard Business School. His 1979 book Energy Future: The Report of the Energy Project led to significant initiatives in energy policy by the Carter administration and became a New York Times bestseller. His article “The Bent Measuring Stick of the Multinational Enterprise” was voted one of the twenty best articles ever published on international business. A federal judge once referred to him as “one of the nation’s foremost experts on corporate governance,” and was quoted on the front page of the Wall Street Journal several times. Robert Stobaugh was born on October 15, 1927, in McGehee (Desha County) to Robert …

Stoneflies

Stoneflies (Phylum Arthropoda, Class Insecta, Order Plecoptera) are a group of aquatic insects well known to fishermen and biologists worldwide. The name Plecoptera means “braided-wings” from the Ancient Greek plekein and pteryx, which refers to “wing.” The name refers to the complex venation of their two pairs of wings, which are membranous and fold flat over their body. Generally, stoneflies are not strong fliers, and several species are entirely wingless. Stoneflies are called “indicator species” because finding them in freshwater environments generally indicates relatively good water quality, as they are quite intolerant of aquatic pollution. They are also prized and imitated by anglers as artificial tied-flies in trout fishing, particularly on Arkansas rivers such as the Eleven Point, Spring, and …

Strepsiptera

aka: Twisted Wing Parasites
aka: The Stylops
The order Strepsiptera, or twisted wing parasites, belongs to the class Insecta, phylum Arthropoda. It is a very small, cosmopolitan order of bizarre parasitoids containing about 624 named species of minute endopterygote insects with nine extant families. They parasitize thirty-four families and several orders of Insecta, including Blattodea (cockroaches), Diptera (flies), Homoptera (leafhoppers), Mantodea (mantises), Hemiptera (true bugs), Orthoptera (grasshoppers and crickets), Zygentoma (silverfish and firebrats), and Hymenoptera (ants, bees, and wasps). Three species of strepsiptera (halictophagids) have been reported from Arkansas hosts (all leafhoppers, Cicadellidae). Strepsiptera have two major groups: the Stylopidia and Mengenillidia. The former, which has endoparasitic females with multiple genital openings, includes seven families: the Bohartillidae (one extant and two fossil species), Corioxenidae (forty-six extant and …

Striped Bark Scorpions

aka: Centruroides vittatus
The striped bark scorpion, Centruroides vittatus, is the only scorpion species recorded from Arkansas, where it is most abundant in the western part of the state. It is the most widely distributed scorpion species in the United States, having been recorded from Missouri, Arkansas, and Louisiana west to eastern Colorado and New Mexico and south to northeastern Mexico. The front body region, which bears the yellowish-brown pedipalps (pincers) and legs below, has a somewhat triangular median dark spot on top pointing backward and extending beyond the eyes. The wide body region that follows has a distinctive pair of broad, dark, longitudinal bands on top. The slender tail-like postabdomen is uniformly yellowish brown, except for the tip of the stinger, which …

Sturgeons

Sturgeons (primitive Acipenseriform) are an ancient group of fishes dating back to the Triassic Period some 245 to 208 million years ago. True sturgeons appear in the fossil record during the Upper Cretaceous (101 to 66 million years ago). There are about twenty-five species of sturgeons, and all belong to the Family Acipenseridae, Order Acipenseriformes. Sturgeons can be found in subtropical, temperate, and sub-Arctic rivers, lakes, and coastlines of North America, with the greatest diversity in Eurasia. In North America, there are eight species that range along the Atlantic Coast from the Gulf of Mexico to Newfoundland, as well as along the West Coast in major rivers from California and Idaho to British Columbia, Canada. The family contains four genera …

Suckers

aka: Catostomid Fishes
Suckers belong to the Family Catostomidae, Order Cypriniformes, and Class Actinopterygii. There are about seventy-two species and thirteen extant genera of these benthic (bottom-dwelling) freshwater fishes. In Arkansas, there are eighteen species in eight genera. Suckers are Holarctic in distribution and primarily native to North America north of Mexico, but the longnose sucker (Catostomus catostomus) occurs in both North America and northeastern Siberia from Alaska, and the Asiatic Sucker (Myxocyprinus asiaticus) is found in the Yangtze River basin in China. Sucker-like fossils are known from Eocene epoch (56 to 33.9 million years ago) deposits from central Asia, and the fossil genus Amyzon, with Ictiobus and Myxocyprinus affinities, occurs in middle Eocene and Oligocene Epoch (33.9 to 23 million years ago) …

Symphylans

aka: Glasshouse Symphylans
aka: Garden Centipedes
aka: Pseudocentipedes
Symphylans belong to the Phylum Arthropoda, Subphylum Labiata, Superclass Myriapoda, and Class Symphyla. About 200 species of symphylans are known worldwide, predominantly in the tropics. There are two families: Scutigerellidae with five genera and about 128 species, and Scolopendrellidae containing nine genera and approximately seventy-three species. There are few reports of symphylans in Arkansas, aside from a new endemic scutigerellid species described in 1992 in Polk County. Many taxa are yet to be discovered and described in the state. The fossil record of symphylans is poorly known; only five species have been recorded, all placed within living genera. They are ancestral arthropods dating back to the early Silurian approximately 430 million years ago, although the only fossil symphylans are known …

Tarantulas

Tarantulas are the largest spiders in Arkansas and are among the most recognizable. Tarantulas are relative newcomers to Arkansas, having arrived in the state about 8,000 years ago. At that time, the climate of North America was much warmer and drier than it is today. Because of higher temperatures and lower amounts of rainfall, habitats more typical of the southwestern United States and the Great Plains expanded eastward into Arkansas and Missouri. Along with drier habitats came many of the animals associated with them, such as tarantulas and scorpions. As the climate became cooler and wetter about 4,000 years ago, these species did not retreat west. Instead, they became isolated within suitable patches of open, dry habitat surrounded by increasing …