Location: South India
looks like injured species, unable to stand.
Well, after a lot of research, I hardy believe that it is a Rhizotrogus aestivus. First of all, the size (2-3cm) you mentioned fits exactly. Secondly, the colour matches fair enough. Finally the antennas and the body shape, may not be seen very well in the picture but I assume that they match. The only thing that I am not sure is the "laziness" of that insect, beacause they are only lazy or clumsy and not active, only when they are about to die.
For more informations check here: https://inpn.mnhn.fr/espece/cd_nom/10907?lg=en
What is the name of this injured species? - Biology
In early August 1996, a large black spider with red hairs on its abdomen was collected by citrus grove workers in St. Lucie County, Florida, west of Ft. Pierce. The workers gave the spider to a citrus survey crew, who brought it back to Gainesville. The first author examined the specimen (which was only half grown) and tentatively identified it as Brachypelma vagans (Ausserer), a species known to be commonly imported by the pet trade under assorted common names (Central American, Guatemalan, Honduran, or Mexican black velvet tarantulas). The accepted common name is Mexican redrump tarantula (Breene 1995).
About a week later, a female and several young spiders were unearthed by grove workers in the same area. Subsequently, several survey expeditions led by the second author captured or destroyed about 100 specimens of all ages from small spiderlings to adult females and males. One of these males was sent to Rick C. West, a tarantula expert and research associate of the Royal British Columbia Museum, for identification. Mr. West confirmed that this species was B. vagans (personal communication 1996). He also noted that the species had been commonly imported into Miami since the early 1970s.
Figure 1. Female Mexican redrump tarantula, Brachypelma vagans. Photograph by Jeffrey Lotz, Division of Plant Industry.
Distribution (Back to Top)
Mexican redrumps were reported from Belize, El Salvador, Guatemala, Honduras and Mexico (Baxter 1993 Smith 1986), but were omitted as a component of the Costa Rican fauna (Valerio 1980). It is now known to occur naturally from Veracruz and the Yucatan Peninsula south along the Gulf coast to northeastern Costa Rica (R.C. West, personal communication 1996).
In Florida, a population was found in a 40-acre citrus grove bordered by irrigation canals on the south and west. The tarantula population initially seemed to be restricted to about one acre in the southwest corner of the grove. Concurrent reports of specimens from the northeast corner of the grove could not be substantiated. Subsequent surveys have found them in burrows along about one half mile of the east bank of the irrigation canal bordering the west side of the grove, as well as a lesser eastern extension along the canal bordering the southern edge of the grove. Wandering males have been found as far as 0.9 miles from the main population site. Later reports from nearby sites have not been verified with specimens, even though extensive surveys have been conducted in the area (to 1.0 mile east and west, 2.5 miles north, 4.0 miles south).
Biology (Back to Top)
Like most tarantulas, the biology of B. vagans is poorly known (Carter 1997). Adult females are 5.0 to 7.5 cm in body length, with a leg span up to 13.5 cm. Adult males are slightly shorter with a much smaller abdomen. The spiders are entirely black except for the long red to reddish-brown hairs on the dorsum of the abdomen females also have reddish-brown hairs on legs III and IV (Baxter 1993). It is a fossorial species (i.e., it digs burrows) adult burrows are 4 to 5 cm in diameter and about 45 cm deep.
Mexican redrumps are nocturnal predators, feeding on ground-dwelling arthropods and possibly on small vertebrates (see Marshall 1996). The enemies of adult tarantulas in Florida likely consist primarily of small predatory mammals, whereas the young tarantulas also would be vulnerable to other arthropod predators, particularly other large terrestrial spiders, as well as frogs and toads. Like most other New World tarantulas, B. vagans defends itself against vertebrate predators with special urticating hairs on its abdomen. If these hairs get on the skin, they itch like bits of fiberglass, but if they get into mucus membranes and especially the eyes, much discomfort or injury could ensue. This species has not been reported to possess a bite serious to people (Breene et al. 1996).
In Florida, males and females with young seemed to be most prevalent in the autumn, although specimens of all sizes can be found year-round. This is unquestionably due to the fact that individuals of this species live for many years. Individuals of some species in this genus are thought to live at least 25 years in the wild, and longer in captivity. Although some congeners are thought to take five to seven years to mature, B. vagans can be raised to adult in captivity in two to three years (Baxter 1993).
Females make large silken eggsacs 4-5 cm in diameter, and the spiderlings stay with the mother for up to several weeks before they disperse. Four captured females made eggsacs in the laboratory, averaging about 100 young per eggsac, although as many as 300 have been reported for this species (Moore 1994), with unpublished reports as high as 800 (Y. Evanou, personal communication 1998).
The establishment of this species in Florida is not surprising. Parts of the Yucatan Peninsula in Mexico are somewhat similar in soil type, vegetation type, and climate to areas of central Florida. We will probably never know exactly how this species came to be introduced into this particular area. One early hypothesis was that a single gravid female escaped or was released. This was based on the fact that one of the earliest captured specimens molted into a deformed male in the laboratory, and it was suspected that the deformity was caused by inbreeding. Since then, many more perfectly normal specimens have been captured, and it is now thought that the specimen was deformed because it was injured during capture.
It is likely that this population has been in this location for over ten years, indirectly supporting the allegation that several specimens were released by a commercial pet importer or breeder at this locality during the 1970s. A reliable sighting of an adult male in 1989 by a pair of herpetologists looking for reptiles along an adjacent paved road was reported in October 1996, after the discovery of this tarantula in Florida was publicized. Given the known maturation time of this species, this would mean that a population has been in the area since at least 1986.
Why they have not become more widespread is not understood, but tarantulas are known to be habitat restricted in the wild and they do not disperse very far (Gertsch 1979). The area where they are established seems to provide the tarantulas with an abundance of food, water, and proper soil to burrow in, so there does not appear to be a need for them to widely disperse. However, the potential for the species to become widespread in Florida given enough time cannot be discounted. The environment of Florida has been plagued by the destructive establishment of exotic organisms for many years (Thomas 1995).
Although the ultimate effect of a naturalized tarantula in Florida cannot at this time be accurately predicted, it would be irresponsible to assume that they will not have a deleterious effect on native wildlife. With this in mind, eradication has been attempted, so far unsuccessfully. If these efforts do not succeed, we still will be able to track the spread of this species and monitor its impact on the environment.
Selected References (Back to Top)
- Baxter RN. 1993. Keeping and Breeding Tarantulas. Chudleigh Publishing, Essex, England. 89 pp.
- Breene RG. 1995. Common Names of Arachnids 1995. American Tarantula Society, Publisher. South Padre Island, Texas. 94 pp.
- Breene RG, Dean DA, Cokendolpher JC, Reger BH. 1996. Tarantulas of Texas: Their medical importance, and world-wide bibliography to the Theraphosidae (Araneae). American Tarantula Society, Publisher. South Padre Island, Texas. 73 pp.
- Carter N. 1997. Who's on CITES and why? Forum of the American Tarantula Society 6: 172-173.
- Gertsch WJ. 1979. American Spiders. 2nd ed. Van Nostrand Reinhold Co., New York. 274 pp.
- Marshall SD. 1996. Old dog learns new trick. Forum of the American Tarantula Society 5: 114-116.
- Moore BH. 1994. Red rumped cannibals. Forum of the American Tarantula Society 3: 14-15.
- Smith A. 1986. The Tarantula: Classification and Identification Guide. Fitzgerald Publishing, London. 178 pp.
- Thomas MC. 1995. Invertebrate pets and the Florida Department of Agriculture & Consumer Services. Florida Entomologist 78: 39-44.
- Valerio CE. 1980. Arañas terafosidas de Costa Rica (Araneae, Theraphosidae). I. Sericopelma y Brachypelma. Brenesia 18: 259-288.
Authors: G.B. Edwards and K.L. Hibbard, Division of Plant Industry, Florida Department of Agriculture and Consumer Services
Originally published as DPI Entomology Circular 394
Photograph: Jeffrey Lotz, Division of Plant Industry, Florida Department of Agriculture and Consumer Services
Web Design: Don Wasik, Jane Medley
Publication Number: EENY-287
Publication Date: May 2003. Reviewed: December 2017. Reviewed: February 2021 .
An Equal Opportunity Institution
Featured Creatures Editor and Coordinator: Dr. Elena Rhodes, University of Florida
What is the name of this injured species? - Biology
Only two of the 18 Nearctic species of Vespula are known from Florida (Miller 1961). These are the two yellowjackets: eastern yellowjacket, Vespula maculifrons (Buysson), and the southern yellowjacket, Vespula squamosa (Drury). One species of Dolichovespula is also present: the baldfaced hornet, Dolichovespula maculata (Linnaeus). The baldfaced hornet is actually a yellowjacket. It receives its common name of baldfaced from its largely black color but mostly white face, and that of hornet because of its large size and aerial nest. In general, the term "hornet" is used for species which nest above ground and the term "yellowjacket" for those which make subterranean nests. All species are social, living in colonies of hundreds to thousands of individuals.
Figure 1. Adult baldfaced hornet, Dolichovespula maculata (Linnaeus), lateral view. Photograph by James L. Castner, University of Florida.
Distribution (Back to Top)
Vespula maculifrons is found in eastern North America, while Vespula squamosa is found in the eastern United States and parts of Mexico and Central America. The baldfaced hornet, Dolichovespula maculata, is found throughout most of the Nearctic region.
Identification (Back to Top)
The three species of Florida yellowjackets are readily separated by differences in body color and pattern. Identification is possible without a hand lens or microscope, and, for this reason, a simple pictorial key is all that is necessary. Color patterns are relatively stable, and their use is further strengthened by morphological characters (Miller 1961). Queens and workers may be separated by abdominal patterns males have seven abdominal segments while females have only six.
Figure 2. Color patterns of Florida yellowjackets.
Biology (Back to Top)
Colonies are founded in the spring by a single queen that mated the previous fall and overwintered as an adult, usually under the bark of a log. Nests may be aerial or terrestrial, depending in part upon the species of the wasp. Some species may construct both types of nest. Regardless of location, each nest is a series of horizontal combs completely surrounded by a paper envelope. Initially, the solitary queen must not only construct the paper brood cells, but also forage for food, lay eggs, feed her progeny, and defend the next from intruders. When the first offspring emerge as adults they assume all tasks except egg laying. The queen devotes the remainder of her life to this task and does not leave the nest again. For most of the season the colony consists of sterile worker females which are noticeably smaller than the queen. Each worker tends to persist at a given task, such as nest building or feeding larvae, for a given day, but may change tasks if the need arises. Working habits apparently are not associated with age as they are in the honeybee. Workers progressively feed larvae a diet of masticated flesh of adult and immature insects, other arthropods, and fresh carrion. Caterpillars appear to be a favorite food. In autumn, larger cells are constructed for the crop of new queens. Larvae in these cells receive more food than do those in normal cells. At the same time, the queen begins to lay unfertilized or male eggs in either large or small cells. After emergence, the new queens mate and seek shelter for the winter. These will be the founders of next spring's colonies. The old founder queen dies, and the workers begin to behave erratically until social order breaks down. With winter's arrival, the remaining colony dies.
Baldfaced hornet, Dolichovespula maculata (Linnaeus): The baldfaced hornet constructs aerial nests often a foot or more in diameter. The wasp is easily recognized by its overall black and white color, and by at least half of the anterior segments of the abdomen (terga I-III) being black. Relatively little is known about this species despite its abundance and wide distribution.
Figure 3. Adult baldfaced hornet, Dolichovespula maculata (Linnaeus), dorsal view. Photograph by James L. Castner, University of Florida.
Figure 4. Larva of the baldfaced hornet, Dolichovespula maculata (Linnaeus). Photograph by Whitney Cranshaw, Colorado State University www.insectimages.org.
Figure 5. Aerial nest of the baldfaced hornet, Dolichovespula maculata (Linnaeus). Photograph by Jerry A. Payne, USDA-Agricultural Research Services www.insectimages.org.
Eastern yellowjacket, Vespula maculifrons (Buysson): Most reports of the eastern yellowjacket indicate subterranean nests, but aerial nests do occur. Haviland described 10 nests, each of which had a nearly spherical ground opening about 1.5 cm in diameter. The nest looks much like that of Dolichovespula maculata except the outside envelope has the consistency of charred paper. As the nest becomes larger, workers remove soil from the burrow. The soil is always deposited about 1 cm distance from the nest. According to Haviland, nests ranged from 9.5 to 30 cm in diameter. The largest nest contained eight levels of comb with over 2800 wasps present. Green et al. (1970) reviewed some unusual above-ground nest locations of Vespula maculifrons including decayed stumps, tree cavities, and between sidings of a home. They also found an exposed nest on the side of a building. Vespula maculifrons is most readily separated from Vespula squamosa by the color patterns.
Figure 6. Adult female eastern yellowjacket, Vespula maculifrons (Buysson). Photograph by Bruce Marlin.
Figure 7. Eastern yellowjacket, Vespula maculifrons (Buysson), nest in hay. Photograph by Georgia Forestry Commission www.insectimages.org.
Southern yellowjacket, Vespula squamosa (Drury): As with Vespula maculifrons, both terrestrial and aerial nests are known for the southern yellowjacket. Gaul (1947) described one ground nest which was 20 cm wide by 20 cm deep. The nest was 22.5 cm below the soil surface. Tissot and Robinson (1954) described five aerial nests for Vespula squamosa. Two nests were constructed in material associated with palm and another in a rolled rug in a garage. A huge nest, about 2.5 m in height, was constructed around the end of a tree stump. A total of 74 layers of comb were found. Evidence suggested that this nest might have been a coalition of two or three independently founded colonies of Vespula squamosa on the same tree.
Figure 8. Adult female southern yellowjacket, Vespula squamosa (Brury). Photograph by Lyle J. Buss, University of Florida.
Figure 9. Adult female southern yellowjacket, Vespula squamosa (Brury). Photograph by Lyle J. Buss, University of Florida.
Figure 10. Southern yellowjacket, Vespula squamosa (Brury), nest dug from ground. Photograph by Gerald J. Lenhard www.insectimages.org.
Economic Importance and Management (Back to Top)
These wasps perform a valuable service in destroying many insects that attack cultivated and ornamental plants. However, nests near homes may prove a source of irritation. If the nests are large or difficult to approach, for example within the walls of a house, the safest procedure would be to hire a pest control operator to eliminate the colony. Any attempt to remove or destroy nests by the layman should be done at night when nest activity is at a minimum. It is important to note that even though nests are relatively inactive at night, any disturbance will result in instant activity by the colony. It is necessary to work cautiously but quickly. Protective clothing is advisable. These wasps are adept at stinging and are especially aroused if danger threatens the nest. Unlike the honeybee, which dies upon inflicting a single sting, vespid wasps may sting as often as they find a target. In fact, when a yellowjacket or hornet is injured it often releases an "alarm pheromone" which quickly results in an aggressive, defensive behavior from other members of the colony.
Yellowjackets and hornets are also attracted to sugar sources, such as berries and flower nectars. However, this becomes a problem when the sugar source is a food or drink being consumed by a human. Sweet items like soft drinks, ripened fruits and watermelons attract bees and wasps. Keep these items covered outdoors. Pick fruit as it ripens and dispose of rotten fruits (Koehler and Oi 2003). In school yards, parks, and other community areas ensure that lids on trash containers are either secure or able to prevent access by wasps as this potential food source (discarded drink containers, fruit remains, etc.) can attract wasps on a continual basis, leading to stinging incidents.
Figure 11. Adult female southern yellowjacket, Vespula squamosa (Drury), feeding on southern blueberry. Photograph by Jerry A. Payne, USDA-Agricultural Research Services www.insectimages.org.
Figure 12. Large local reaction to a sting by an eastern yellowjacket. Photograph by Terry Price, Georgia Forestry Commission www.insectimages.org.
Selected References (Back to Top)
- Evans HE. 1963. Wasp farm. The Natural History Press, Garden City, NY. 178 pp.
- Evans HE, Eberhard MJW. 1970. The wasps. The University of Michigan Press, Ann Arbor, MI. 265 pp.
- Gaul AT. 1947. Additions to vespine biology III: Notes on the habits of Vespula squamosa Drury (Hymenoptera, Vespidae). Bulletin of the Brooklyn Entomological Society 43: 87-96.
- Green SG, Heckman RH, Benton AW, Coon BF. 1970. An unusual nest location for Vespula maculifrons (Hymenoptera: Vespidae). Annals of the Entomological Society of America 64: 1197-1198.
- Haviland EE. 1962. Observations on the structure and contents of yellowjackets' nests (Hymenoptera). Proceedings of the Entomological Society of Washington 64: 181-183.
- Koehler PG, Diclaro JW. (2017). Stinging or Venomous Insects and Related Pests.University of Florida/IFAS. EDIS. (22 April 2020)
- Landolt PJ, Reed HC, Heath RR. 1999. An alarm pheromone from heads of worker Vespula squamosa (Hymenoptera: Vespidae). Florida Entomologist 82: 356-369.
- Miller CDF. 1961. Taxonomy and distribution of Nearctic Vespula. Canadian Entomologist Supplement 22: 1-52.
- Reed HC, Landolt PJ. 2000. Application of alarm pheromone to targets by southern yellowjackets (Hymenoptera: Vespidae). Florida Entomologist 83: 193-196.
- Tissot AN, Robinson FA. 1954. Some unusual insect nests. Florida Entomologist 37: 73-92.
- Vetter R, Visscher PK. (2004). Yellowjacket Wasps and their Control. Insect Information. (22 April 2020)
Authors: E.E. Grissell (retired), Florida Department of Agriculture and Consumer Services, Division of Plant Industry and Thomas R. Fasulo, University of Florida
Originally published as DPI Entomology Circular No. 142. Updated for this publication.
Photographs: Lyle J. Buss and James L. Castner, University of Florida Jerry A. Payne, USDA-Agricultural Research Services Terry Price, Georgia Forestry Commission Gerald J. Lenhard Whitney Cranshaw, Colorado State University Bruce Marlin.
Web Design: Don Wasik, Jane Medley
Publication Number: EENY-81
Publication Date: May 1999. Latest revision: November 2013. Reviewed: April 2020.
An Equal Opportunity Institution
Featured Creatures Editor and Coordinator: Dr. Elena Rhodes, University of Florida
Spiny Dogfish. Photo © George Burgess
This long, slender dogfish has a pointed snout, large eyes, and spines in front of its two dorsal fins. It is a brownish slate color, fading to a pale underbelly, with rows of white spots down its upper body that fade with age. These migratory, schooling sharks spend winters in deeper water where they possibly don’t eat much, and summer in coastal warm waters where they eat bony fish, smaller sharks, and many other sea animals. They rarely grow longer than 39 inches except in the cases of older females which have been caught up to 49 inches long.
Order: Squaliformes Family: Squalidae Genus: Squalus Species: acanthias
English language common names include spiny dogfish, blue dog, common spinyfish, darwen salmon, dogfish, grayfish, Pacific dogfish, piked dogfish, rock salmon, spiky dog, spotted spiny dogfish, spring dogfish, spur dogfish, spur dog, victorian spotted dogfish, white-spotted dogfish, and white-spotted spurdog.
The common name “dogfish” originated from fishermen who described these fish as chasing smaller fish in large dog-like “packs”.
Other language common names include abou shoka (Arabic), abura-tsunozame (Japanese), abushoka (Arabic), agullat (Catalan), aiguillat commun (French), akula (Bulgarian), an fiogach gobach (Irish), cação-de-espinho (Portuguese), câine de mare (Rumanian), can bianco (Italian), doornhaai (Dutch), doringhai (Afrikaans), dornfisch (German), eqalussuaq kukilik (Greenlandic), galhudo (Portuguese), galludo (Spanish), grundhai (German), háfur (Icelandic), katran (Russian), kentroni (Greek), koinga (Maori), kolen (Polish), mazzola (Maltese), mielga (Spanish), morsko kuce (Bulgarian), pigghaj (Swedish), pinchudo (Spanish), qozan qetan (Hebrew), rechin (Rumanian), skyllos (Greek), spikkel-haai (Afrikaans), and spinarolo (Italian).
Importance to Humans
Spiny dogfish. Photo courtesy Virginia Institute of Marine Science
Total landings of spiny dogfish peaked in 1974 at 27,400 metric tonnes, followed by a sharp decline, stabilizing at 5,900 mt during the 1980s. In the 1990s, landings rose dramatically, with over 28,000 mt taken in 1996. Spiny dogfish are caught primarily with otter trawls and sink gill nets. This species is used in the popular British dish “fish and chips” as well as marketed for its oil and as fish meal. This species can cause tremendous damage when entangled in commercial nets.
Danger to Humans
In general, the spiny dogfish poses little if any threat to humans. As the English common name “spiny dogfish” alludes to, this species has spines on the dorsal fins that can result in nasty wounds if not handled carefully. The dogfish uses these spines to defend itself, curling in a bow and striking at any threatening predator.
Spiny dogfish. Photo courtesy National Marine Fisheries Service
Spiny dogfish are slow to mature and must be managed carefully. This species is extremely vulnerable to over fishing and are currently on the brink of collapse. They have a long gestation period, produce small litters of pups, and are slow growing. Commercial fishermen target the mature females because they grow to larger sizes than males. Females don’t reach sexual maturity until 12 years of age, giving birth to approximately 6 pups after a 2-year gestation period. The dogfish fishery increased dramatically in the U.S. during the 1990s, resulting in a 75% reduction in mature females, leading to record low numbers of pups over the past seven years.
In 2001, the Atlantic States Marine Fisheries Commission (ASMFC) voted to extend an emergency action that closes state waters to fishing for the vulnerable spiny dogfish. This was in response to heavy fishing that devastated dogfish populations during the 1990s. In late 2000, a fishery management plan for the spiny dogfish began to be developed, followed by its approval in November 2002. Federal and state recovery plans are currently in place but continually challenged. In mid 2003, the ASMFC held a vote on a motion to lower the spiny dogfish quota to a level supported by scientific data. However, this motion fails to achieve the required two-thirds majority. The National Marine Fisheries Service, with new stock assessment data predicting the collapse of the spiny dogfish population, closed federal waters to dogfish fishing in July 2003.
The National Marine Fisheries Service currently regulates shark fisheries, including the spiny dogfish, in federal waters setting forth closures when quotas are reached for each shark species group (large coastal sharks, small coastal sharks, and pelagic sharks).
The spiny dogfish is considered as “Vulnerable” by the World Conservation Union (IUCN) due to intense fishing pressure. The IUCN is a global union of states, governmental agencies, and non-governmental organizations in a partnership that assesses the conservation status of species.
World distribution map for the spiny dogfish
Spiny dogfish are found in the western Atlantic Ocean from Greenland to Argentina and in the eastern Atlantic from Iceland and Murmanski Coast (Russia) to South Africa including the Mediterranean Sea and Black Sea. In the western Pacific Ocean, the spiny dogfish occurs from the Bering Sea to New Zealand while in the eastern Pacific, this species is found from the Bering Sea to Chile.
Spiny dogfish schooling behavior, if you look closely, you can see dorsal fins of numerous individuals. Photo courtesy NOAA
Spiny dogfish are found epibenthically, however they do move through the water column, up to surface water. These dogfish are found in inshore and offshore waters over the continental shelf to depths of 2950 feet (900 m). Although they can tolerate brackish water, spiny dogfish prefer full-strength seawater and do not enter freshwater habitats.
Spiny dogfish swim in large schools with individuals of the same size class staying together as they grow. Schools can consist of either mature large females, medium size mature males or immature females, or of small immature fishes of both sexes. Immature dogfish tend to school offshore while schools of mature females are often observed inshore.
Dogfish are a highly migratory species. Found primarily north of Cape Cod in the summer, they move south to Long Island in the fall and as far south as North Carolina in the winter. During the spring, they begin their migration north, reaching Georges Bank in March and April. They are absent along the coast of Canada and Maine until late June and July.
Spiny dogfish (Squalus acanthias). Illustration courtesy FAO, Species Identification and Biodata
1. Dorsal fins both preceded by a single spine
2. First dorsal fin is obviously larger than second dorsal fin
4. Body scattered with small white spots
Spiny dogfish, notice the moderately large eye and somewhat flattened head (top), and dorsal fin spines on the spiny dogfish (bottom). courtesy NOAA
The spiny dogfish has a slender, elongate body and a moderately flattened head. The snout is narrow, tapering to a pointed tip. The eyes of this dogfish are moderately large. The first dorsal fin is located about halfway between the pectoral and pelvic fin origins and behind the rear tips of the pectoral fins. The second dorsal fin is about two-thirds the size of the first and is located behind the pelvic fins.
There are sharp dorsal fin spines at the anterior margins of the dorsal fins with the first about half as long and the second nearly as long as the anterior margins of their respective fins. The pectoral fins form nearly perfect equilateral triangles with rounded rear tips and slightly concave rear margins. The pelvic fins are closer to the second dorsal fin than the first dorsal. There are low lateral keels located on the caudal peduncle. There is no notch on the upper caudal lobe and the lower caudal lobe is not well-developed. There is no anal fin on the spiny dogfish.
The dorsal surface of the spiny dogfish is slate-colored and may have a brownish cast. There is a lateral row of small white spots along each side from above the pectoral fins to above the pelvic fins. These spots of conspicuous on immature fish, fading with growth until they disappear entirely from some individuals. The edges of the first and second dorsal fins and the caudal fin appear dusky at birth but quickly fade. The ventral surface of the spiny dogfish ranges from pale gray to pure white.
Upper and lower teeth of a spiny dogfish. Illustration courtesy Bigelow & Schroeder (1948) FWNA
The upper and lower teeth are small and similar in shape with oblique points bent toward the outer corners of the mouth. The cusps are deeply notched outward with a single sharp point. These form a nearly continuous cutting edge from one corner of the mouth to the other. There are 28 upper teeth and 22-24 lower teeth in the jaws of the spiny dogfish.
Dermal denticles of the spiny dogfish are small and low with three cusps. The central ridge is prominent and the lateral extensions are wing-like in appearance.
Spiny dogfish. Photo courtesy NOAA
Size, Age, and Growth
The average size of the spiny dogfish is 28-39 inches (70-100 cm) with adult males ranging from 24-35 inches (60-90cm) and adult females from 30-42 inches (76-107 cm) in length. The maximum length of males is 39 inches (100 cm) and females 49 inches (124 cm). Mature females reach weights of 7.1-9.9 pounds (3.2-4.5 kg), with a maximum recorded weight of 21.6 pounds (9.8 kg). The all-tackle game fish record is 15.7 pounds (7.14 kg) caught off the coast of Ireland, 1989. Females reach maturity at 12 years of age and from 29.9-30.1 inches (76-78 cm) in length, while most males mature at 6 years and about 23.6 inches (60 cm) in length. They live up to 25-30 years of age.
Spiny dogfish feed on mackerel. Photo courtesy NOAA
Dogfish have earned a bad reputation among fishermen for their voracious appetites. They are known to drive off commercially caught fish including mackerel and herring, while consuming large numbers of them. Spiny dogfish have been observed biting through nets to get at fishes, releasing many of them in the process. Schooling pelagic fishes make up the majority of the diet of the spiny dogfish. These include herring, menhaden, capelin, sand lance, and mackerel. Other consumed species include wolffish and flatfishes, as well as squid, jellyfish, shrimps, crabs, octopus, and sea cucumbers. It is believed that spiny dogfish rarely feed during the winter months when they stay in deeper waters based upon their very thin appearance in early spring in coastal waters.
Spiny dogfish embryo. Photo © Jose Castro
Mating typically occurs in offshore waters with fertilization occurring internally. This is followed by ovoviviparous development. After 4-6 month of development, the membrane providing nourishment to the embryo breaks down. This leaves the yolk-sac to provide nourishment during the remaining 17-19 months of gestation. This species is thought to have the longest gestation period of any vertebrate (up to 24 months). The young are born head-first with cartilaginous sheaths on the spines to protect the mother from injury. Litter sizes average 6-7 but varies between 1 and 15. The newborn pups range from 8-13 inches (20-33 cm) in length.
Spiny dogfish are been documented in the stomachs of cod, red hake, and goosefish, as well as other spiny dogfish. Larger species of sharks as well as seals and killer whales, although in fewer numbers, also feed on the spiny dogfish.
Firsthand observation of a spiny dogfish giving birth in the wild near Rockport, MA (August 2002).
Killer whales feed on small sharks including the spiny dogfish. Photo courtesy National Marine Mammal Laboratory
The spiny dogfish was originally described as Squalus acanthias by Karl Linneaus in 1758. However, many synonyms referring to this species have been used in past scientific literature. These include Squalus fernandinusMolina 1782, Acanthias vulgaris Risso 1827, Acanthias americanus Storer 1846, Spinax mediterraneanus Gistel 1848, Squalus sucklii Girard 1855, Squalus suckleyi Girard 1855, Acanthias sucklii Girard 1855, Acanthias linneiMalm 1877, Acanthias lebruni Valliant 1888, Acanthias commun Navarette 1898, Squalus wakiyae Tanaka 1918, Squalus kirki Phillipps 1931, Squalus barbouri Howell-Rivero 1936, and Squalus acanthias africana Myagkov & Kondyurin 1986.The valid genus name Squalus is Latin for “a kind of sea-fish” while the species name acanthias translates as “a prickly thing”, describing the spines found on the dorsal fins of this dogfish.
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Some people go on to become zoologists after getting a bachelor’s degree in biology or a related field. They combine a degree in biology with animal work, and may go on to get a master’s or doctorate specifically in zoology. However, some colleges do offer bachelor’s degrees specifically in zoology. Zoology bachelor’s degree programs involve general classes in the basic sciences– biology, chemistry, physics, and math– and also involve upper-level classes on a variety of subjects, from animal science to microbiology to wildlife ecology. These classes meet the requirements for graduate studies in zoology if someone who has not received a zoology bachelor’s degree goes on to do graduate work in zoology, they must meet several basic requirements. Usually these requirements include, in addition to biology courses, at least three semesters of chemistry, a year of physics, and a year of calculus. All of these courses are usually taken in the process of getting a bachelor’s degree in biology. If one has deficiencies, he or she may be able to make up for it by taking these courses before or while attending graduate school.
Reactive oxygen species in inflammation and tissue injury
Abstract Reactive oxygen species (ROS) are key signaling molecules that play an important role in the progression of inflammatory disorders. An enhanced ROS generation by polymorphonuclear neutrophils (PMNs) at the site of inflammation causes endothelial dysfunction and tissue injury. The vascular endothelium plays an important role in passage of macromolecules and inflammatory cells from the blood to tissue. Under the inflammatory conditions, oxidative stress produced by PMNs leads to the opening of inter-endothelial junctions and promotes the migration of inflammatory cells across the endothelial barrier. The migrated inflammatory cells not only help in the clearance of pathogens and foreign particles but also lead to tissue injury. The current review compiles the past and current research in the area of inflammation with particular emphasis on oxidative stress-mediated signaling mechanisms that are involved in inflammation and tissue injury.
Quarians are generally shorter and of slighter build than humans. Quarians have an endoskeleton, lips, teeth, and two eyes with eyelids and tear ducts. Their ears or ear analogues differ in a noticeable fashion from those of humans, with references made to "what [passes] for the quarian version of an ear". Their eyes can see into the ultraviolet end of the spectrum their suit HUDs can show information in those wavelengths. Quarian facial structure and hair actually makes them the most similar to humans in physical appearance.
They also have three thick fingers on both hands which include a thumb, an index finger, and a long finger, similar to the middle fingers for humans, as well as three toes on each foot. Their lower legs are bowed backwards significantly, compared to asari or humans. Aside from hands and legs, their general body shape and sexual dimorphism is similar to humans. Male quarians, however, appear to lack a third toe. Like humans, quarian blood is red.
The most distinguishing feature of quarian biology is their weak immune system, compounded by centuries of living in sterile environments. As a result, all quarians by necessity dress in highly sophisticated enviro-suits, to protect them from disease or infection if they are injured. Their suits can be compartmentalized in the event of a tear or similar breach to prevent the spread of contaminants (similar to a ship sealing off bulkheads in the event of a hull breach). Along with their suits, quarians also have extensive cybernetic augmentations integrated into their bodies. A quarian's lifespan is roughly equal to a human's, but is prone to be less if infection breaks into the suit.
Quarian immune systems have always been relatively weak, as pathogenic microbes were comparatively rare in their homeworld's biosphere. Furthermore, what few viruses and other microbes were native to their homeworld were often at least partly beneficial to them, giving them a symbiotic relationship with their environment. After living aboard the Migrant Fleet for generations, the quarians' immune systems have atrophied further still due to the years in the sterile environment of the Migrant Fleet. As such, quarians are given various vaccinations and immunizations to help ward off disease. However, they prefer the safety of their suits even in clean environments and are reluctant to remove them without a good reason.
A quarian who wishes to remove their suit must take antibiotics, immuno-boosters, herbal supplements, or the like in order to do so safely, and even then there are inherent risks. As a result, physical acts of affection are difficult for quarians, even for the purposes of reproduction. Ships in the Migrant Fleet often contain "clean rooms" where quarians can give birth or undergo medical procedures in relative safety, though there are always risks. The most intimate thing quarians can do is link their suit environments. However, doing so guarantees a quarian will get sick, although they will usually adapt over time.
Like turians, the quarians are a dextro-protein species of reverse chirality from humans and asari. The food of levo-protein races such as humans or asari is at best inedible and at worst poisonous, most likely triggering a dangerous allergic reaction. Quarians who want to taste something (other than the refined edible paste issued to all who leave on their Pilgrimage) can eat specially purified turian cuisine, though the typical quarian diet is vegan, as livestock were found to possess an inefficient resource-to-calorie ratio when stored on the Migrant Fleet.
Other than the oft-mentioned maladjusted immune systems, the quarians have surprisingly robust physiology. Grunt's tank imprints specifically deem several species soft and easy to kill, but not quarians. One extensively tortured quarian survives for a while without an enviro-suit before dying from his injuries. Another endures traveling through multiple racial environments without a suit, dealing with things like elcor high gravity and drell aridity before dying in the high-pressure volus zone after a considerable amount of time there.
We are becoming a new species, we are becoming Homo Evolutis
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At TED 2009, now halfway through the near-weeklong binge of activities and presentations, Juan Enriquez energized and perhaps terrorized attendees with his brief look into the future of human affairs, and indeed, of the human species. What made Enriquez' presentation so engaging was that his vision wasn't that far off, this sci-fi future that he spoke of it's the future that is unveiling itself right before us, a future that we will all likely watch arrive, and our children will come to know as reality.
Chairman and CEO of Biotechonomy, Enriquez says that humanity is on the verge of becoming a new and utterly unique species, which he dubs Homo Evolutis. What makes this species so unique is that it "takes direct and deliberate control over the evolution of the species." Calling it the "ultimate reboot," he points to the conflux of DNA manipulation and therapy, tissue generation, and robotics as making this great leap possible.
We are already in the midst of minor improvements to the human body and mind Enriquez gave examples of growing new tissues for successful transplant, programmable cells, and augmenting our abilities through robotics. As this trend accelerates, more and more aspects of the human experience, of the human life, will be capable of scientific manipulation. While some improvement may come post-birth, our understanding of DNA and biology may lead to something much bigger.
The day may come when we are able to take the best biology of the known animal kingdom and make it part of our own. This isn't just about being a bit stronger, or having perfect eyesight our whole lives. All of our organs and limbs have weaknesses that can be addressed, and there are also opportunities to go beyond basic fixes and perform more elaborate enhancements. At a private lunch on Thursday, Enriquez spoke of a young girl who, after suffering a knee injury, received tendon replacement therapy centered around tendons grown in a lab. It not only fixed her knee, but made it stronger than normal. Later in life as she pursued life as a professional skier, the coach actually asked that she have the same surgery on her other knee to increase her abilities.
The point was clear: one day it will be possible for everyone to have stronger joints, bones, etc., thanks to work being done today, work which may ultimately be delivered into DNA. We would become a species that could, literally, control its own biological destiny.
All TED talks are limited to 18 minutes (in theory), so Enriquez wasn't able to elaborate beyond the basic points, nor was he able to field questions, which would have undoubtedly included essentialist objections to his notion of speciation or evolution. But for those 18 minutes, Enriquez painted the clearest path towards humanity's Borg-like future I've ever had the pleasure of hearing. It is no coincidence that he also mentioned, briefly, the need for ethical dialog around these issues.
All of this, coincidentally, was prefaced by a short discussion about our economic woes as of late, and Enriquez's view of the way out. With the massive growth in mandatory spending, Enriquez called for an end to entitlements, and a return to the acceptance of austerity. Tough times are unavoidable.
He also had comments on the workforce that were more relevant to his presentation. Like many, Enriquez believes that our workforce is going to work later and later in life, to the age of 70 and beyond. This is necessary because we need more production, and also because we must reduce the amount of time seniors spend collecting money from governments. In this way, the dawn of Homo Evolutis will not merely be occasioned by our desire to live longer, but by the necessity of it.
A species considered to be facing a very high risk of extinction in the wild.
A species considered to be facing a high risk of extinction in the wild.
Sharks and Rays:
The IUCN Red List also re-assesses how species are doing over time. If things have improved for a given species&mdashmeaning the population has grown due to conservation efforts&mdashthen that species will be &lsquodownlisted&rsquo to a less critical status. For example, the giant panda was downlisted from &lsquoendangered&rsquo to the lesser status of &lsquovulnerable&rsquo in 2016 thanks to dedicated work to protect them. The flip side of this is &lsquouplisted,&rsquo an indication that a species population is dropping.
Protecting the most vulnerable wildlife
WWF works to save at-risk wildlife from around the globe. We&rsquore protecting and connecting the habitat of endangered tigers stopping poaching of the critically endangered black rhino and fighting back against the illegal trade of ivory from vulnerable African elephants.
Join us to make change. Speak up for species and places through WWF's Action Center.