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What kind of larvae are these?

What kind of larvae are these?


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My uncle was helping us spray the garage for ants, and he stumbled across a huge batch of some type of larvae. According to him…

"It looked like a long, narrow clump of mud. When I broke it open, all of these larvae fell out. Whatever bugs were inside scattered pretty quickly!"

  • Geography: We're in Los Angeles, CA (southwestern USA)
  • Season: It's late summer here (early September)

Exhibit A: The pile of larvae…

Exhibit B: A similar husk of "mud" found in our garage. When it was shattered, nothing fell out…

My uncle thinks it's termites… I'm certainly hoping it isn't.


I think that it is termites larvae. For more info check this : Termites follow the typical life cycle of insects that have a gradual life cycle: they begin as eggs, and then enter nymphal to adult stages. In termite development, newly hatched termites are sometimes referred to as “larvae,” which is not to be confused with the larvae of complete metamorphosis insects like flies.

Termite larvae typically hatch within a few weeks. They are approximately the same size as the eggs from which they hatched and are immediately tended to by worker termites. They often comprise a large part of a termite colony.

Similar to other insect young, termite larvae go through a series of molts, during which they shed their skins. From the larval stage, termite larvae may evolve into other members of the colony's castes.

If you suspect you have termite activity in or near your home, contact a pest control professional. Termite damage can go undetected and result in significant financial loss from their damage. A termite inspector can inspect a home for signs of activity and conditions that are attractive to termites. They also can offer services to treat and protect the home from potential future damage.


What kind of larvae are these? - Biology

The tobacco hornworm, Manduca sexta (L.), is a common pest of plants in the family Solanaceae, which includes tobacco, tomato, pepper, eggplant, and various ornamentals and weeds (del Campo and Renwick 1999). Caterpillars in the family Sphingidae are known as hornworms, due to their worm-like body shape and the presence of a small, pointed &ldquohorn&rdquo at their posterior (Figure 1). The adult stage of Manduca sexta is a heavy-bodied moth that resembles a hummingbird, and Manduca adults are commonly referred to as hawkmoths or hummingbird moths (Figure 2). The larval stage (hornworm) of this species is more often encountered, as it is resides on the host plant during the day and can cause significant defoliation of economically important crops.

Figure 1. Manduca sexta (L.), the tobacco hornworm. Photograph by Lyle J. Buss, University of Florida.

Figure 2. Manduca sexta (L.), the tobacco hornworm, adult. The adult form of this species is also known as Carolina sphinx moth or, generally, a hawk moth. Photograph by Lyle J. Buss, University of Florida.

This species may be confused with the tomato hornworm, Manduca quinquemaculata (Haworth), a closely related species that also preferentially feeds on solanaceous plants. These species can be distinguished from one another by comparing the markings on the body of larvae and on the abdomen of the adults. In addition to its pest status, Manduca sexta is an important model organism in the field of entomology, particularly insect physiology (Koenig et al. 2015). Manduca sexta has been used for a series of important studies that contributed to the understanding of insect endocrinology and development (Nijhout and Williams 1974, Bollenbacher et al. 1981). Specifically, this species was used to investigate the interactions between endogenous hormones and environmental cues that signal development through multiple instars and the onset of pupation (Riddiford et al. 2003).

Distribution (Back to Top)

The tobacco hornworm is found throughout the United States (north to the southern portion of Canada), Central America, and the Caribbean (Cranshaw 2004). This species is more commonly encountered in southern states, but its range may overlap with the closely related tomato hornworm, Manduca quinquemaculata, which predominates in the northern United States (Cranshaw 2004).

Description (Back to Top)

Eggs: The eggs of Manduca sexta are deposited on the leaves of the host plant and hatch one to three days after oviposition. Eggs are about 1 mm in diameter, greenish in color, and slightly iridescent (Deel 1999).

Figure 3. First instar larva of Manduca sexta (L.), the tobacco hornworm, consuming its eggshell after emerging. Photograph by Lyle J. Buss, University of Florida.

Larvae: The common name tobacco hornworm refers to the larval stages of Manduca sexta the caterpillars are robust and bright green, with white, diagonal striped markings and a small protrusion (the &ldquohorn&rdquo in hornworm) on the last abdominal segment (Figure 4) (Cranshaw 2004). Manduca sexta larvae undergo four or five instars, gradually increasing in size to about 80 mm in length in the final instar (Deel 1999, Campbell 2017). The tobacco hornworm looks very similar to tomato hornworm, Manduca quinquemaculata (Figure 5), and their range and host plants can overlap. Body markings and horn coloration can be used to distinguish between the two species. The tobacco hornworm has whitish diagonal lines on the body and a reddish horn, whereas the tomato hornworm has V-shaped markings on the body and a black horn (Cranshaw 2004).

Figure 4. Late instar larva of Manduca sexta (L.), the tobacco hornworm. Photograph by James Castner, University of Florida.

Figure 5. Late instar larva of Manduca quinquemaculata (Haworth), the tomato hornworm. Photograph by John Capinera, University of Florida.

Prepupae and pupae: At the end of the final larval instar, the hornworm enters what is considered the prepupal stage. This stage is characterized by wandering behavior and selection of a pupation site, followed by the formation of the pupal cell below the leaf litter or soil substrate. Once the pupal cell is excavated, the prepupal stage transitions into the pupal stage as the insect&rsquos cuticle hardens and darkens, forming the pupa. The pupa of Manduca sexta is a dark, reddish-brown color with a maxillary loop at the anterior end and a pointed posterior end (Figure 6 ) (Deel 1999). Depending on the time of year and number of generations (two is typical in most areas), overwintering may occur during this stage (Cranshaw 2004). The sex of Manduca sexta can be determined by looking for markings on the fifth instar larvae, the prepupae or the pupal case, or the adult (Willott 2003).

Figure 6. Pupa of Manduca sexta (L.), the tobacco hornworm. Note the maxillary loop (right). Pupae are found belowground or deep in the leaf litter. Photograph by Lyle J. Buss, University of Florida.

Adults: The adult stage of Manduca sexta is a robust, agile moth known as the Carolina sphinx moth or the tobacco hawkmoth (although the Entomological Society of America does not list an approved common name for the adult moth). Adults have a wingspan of 3.75 to 4.75 in (9.5 to12 cm) for the forewings hindwings are small in comparison (Lotts and Naberhaus 2017). The wings have a mottled pattern of white, brown, and black with distinct light and dark bands on the hindwings. When at rest, the wings fold back giving the moth a triangular shape and providing camouflage (especially when resting on trees with lichens) (Figure 1). The Carolina sphinx moth has six pairs of yellowish-orange spots (five large pairs of spots, with the posterior-most pair comparatively small) arranged vertically on the grayish-brown abdomen (Figure 7) the adult of the tomato hornworm (Figure 8) is similar in appearance but has five pairs of yellowish-orange spots (Cranshaw 2004, Lotts and Naberhaus 2017).

The adult moths are also referred to as hummingbird moths due to their tendency to fly nimbly between flowers, hovering over each to extract nectar with their long proboscis. Some moths in the Sphingidae family are considered to be beneficial pollinators, an interesting ecological role in contrast to the destructive nature of the larvae. After eclosing (emerging as an adult from the pupal stage), the moths are crepuscular (active at dawn and dusk) and obtain nectar from a variety of flowering plants. Females can produce eggs three to four days after emerging and mating, and each female can produce many eggs (some sources say up to 1,000) in her lifetime of several weeks (Deel 1999).

Figure 7. Adult form of Manduca sexta (L.), the tobacco hornworm, also known as a Carolina sphinx moth or hawk moth. Photograph by Lyle J. Buss, University of Florida.

Figure 8. Adult form of Manduca quinquemaculata (Haworth), the tomato hornworm. Photograph by John Capinera, University of Florida.

Description and Life Cycle (Back to Top)

The tobacco hornworm is a specialist of solanaceous plants, like pepper, tobacco, and tomato. Plants in the family Solanaceae contain steroidal and triterpenoid glycosides, chemical compounds that play an important role in the biology of Manduca sexta (Haribal et al. 2006). One steroidal glycoside in particular, indioside D, was observed to induce feeding preference in naïve larvae, causing these individuals to specialize solely on solanaceous foliage (del Campo et al. 2001). Female moths select plants for oviposition based on chemical cues, such as odor, detected via their antennae (Reisenman et al. 2009, Spathe et al. 2013). Studies suggest that female moths will not oviposit on plant hosts that have already been fed on by larvae, likely detecting a blend of plant volatiles released by the plant in response to the feeding (Reisenman et al. 2009, Spathe et al. 2013).

As mentioned earlier, this species has been used extensively as a model organism in experiments related to insect development, genetics, and behavior. In the lab they can be successfully reared on artificial diet. Manduca sexta larvae reared under laboratory settings will not feed exclusively on solanaceous plants, accepting plant tissue from a variety of other plants in different plant families. However, caterpillars reared initially on a solanaceous diet were significantly less likely to feed on non-solanaceous leaves, even when no other food option was presented (del Campo et al. 1999). Additional studies suggest that olfactory cues are supplemented by gustatory (taste-based) cues in Manduca sexta larvae, and that feeding preference is largely a function of early feeding experiences (Glendinning et al. 2009).

Host Plants (Back to Top)

Both male and female adult moths feed on nectar from a variety of flowering plants. Adults are active at night, further strengthening the conclusion that larval host plants are located using chemical, rather than visual, signals (Reisenman et al. 2009).

Larval host plants include: Datura wrightii (jimsonweed), Nicotiana attenuata (wild tobacco), Proboscidea parviflora (devil&rsquos claw) (Spathe et al. 2013), Lycopersicon esculentum (tomato) (Reisenman et al. 2009), Capsicum annuum (bell pepper) (Fraser et al. 2003), and Solanum tuberosum (potato) (de Campo et al. 2001).

These insects feed only on solanaceous plants, most commonly on tomato and tobacco. They have been recorded on other vegetables such as eggplant, pepper, and potato, but this is rare. Several Solanum spp. weeds are reported to serve as hosts. Adults imbibe nectar from flowers of a number of plants, and can be seen hovering about flowers at dusk.

Damage (Back to Top)

The larval stages of Manduca sexta are voracious feeders. Larvae feed by consuming the leaves of solanaceous plants, often stripping entire leaves to the midrib, defoliating the plants (Figure 9). Though considered a common garden pest, tobacco hornworm can cause significant economic damage to tobacco crops and occasionally tomato and potato crops. Larvae may feed on unripe, green fruit, leaving large wounds and exposing the fruit to opportunistic plant pathogens (Figure10) (Cranshaw 2004).

Figure 9. Feeding damage to tomato foliage caused by Manduca sexta (L.), the tobacco hornworm. Photograph by James Castner, University of Florida.

Figure 10. Feeding damage to young tomato fruit caused by Manduca sexta (L.), the tobacco hornworm. Photograph by James Castner, University of Florida.

Management (Back to Top)

Tobacco hornworms can be controlled in various ways and immediate management is recommended if this pest is detected in a garden or field setting. In smaller operations, like a home garden, hand picking and destruction of the caterpillars is an effective way to reduce the population. This method of cultural control requires regular scouting of solanaceous plant species, looking for signs of feeding damage. The caterpillars themselves can be hard to see against the green foliage of the host plant, so careful monitoring of defoliation or the presence of frass (Figure 11) may be better indications of caterpillar presence.

Figure 11. Frass on the host plant can be an indication of feeding by Manduca sexta (L.), tobacco hornworm. Photograph by James Castner, University of Florida.

Biological control is another method of management, using Bacillus thuringiensis (Bt), a naturally-occurring soil bacterium that produces a protein that acts as a fatal endotoxin when consumed by Lepidopteran larvae (and the larvae of some other insect taxa). This product is widely-available and safe for use around pollinating insects because it has to be consumed in order to be effective. Additionally, Bt is suitable for use in organic growing operations. This pesticide is more effective on earlier instar larvae, as a smaller amount must be consumed for effective control.

Tobacco hornworms have several natural enemies, including vertebrate species that feed on caterpillars, such as birds and small mammals, and insects like lacewing and lady beetle larvae that consume the eggs and early instar larvae. Wasps are a common predator of hornworms. Paper wasps and other insects that provision prey for their young will take hornworms from the host plant, paralyze them, and place them into the nest cells containing the wasp&rsquos eggs as a future food source. Parasitoid wasps, like Cotesia congregata, use hornworms as a food source for their developing young. These wasps deposit their eggs inside the hornworm&rsquos body and the larval wasps develop within the caterpillar, feeding on it as they progress through their life cycle. When pupation takes place, the immature wasps spin small, white, silken cocoons that protrude from the body of the still-living caterpillar (Figure 12) (Crockett et al. 2014). The cocoon-covered hornworms are a sight of great interest in the garden, and many fear that the parasitized caterpillars will have a negative impact on their garden. In fact, the opposite is true because the hornworm will eventually die and several adult wasps will emerge, mate, and seek out additional hornworm hosts for their eggs.

Figure 12. Late stage larva of Manduca sexta (L.), the tobacco hornworm, that has been parasitized by a parasitoid wasp. Note the white, silken cocoons protruding from the body of the caterpillar. Photograph by Lyle J. Buss, University of Florida.

A number of chemical insecticides exist for management of tobacco hornworm and other caterpillars. For specific recommendations, contact your local County Extension Office. When using any chemical product, whether biological or synthetic in nature, it is the law to follow label instructions and precautions for safety and suitability of the pest and crop.

Selected References (Back to Top)

  • Bollenbacher WE, Smith SL, Goodman W, Gilbert LI. 1981. Ecdysteroid titer during larval-pupal-adult development of the tobacco hornworm, Manduca sexta. General and Comparative Endocrinology 44: 302-306.
  • Campbell D. (2017). Manduca sexta, Carolina sphinx moth. Encyclopedia of Life. (1 October 2017)
  • Cranshaw W. 2004. Hornworms/Sphinx moths. Garden Insects of North America: The Ultimate Guide to Backyard Bugs. Princeton University Press, Princeton, New Jersey, USA. p. 146-149.
  • Crockett CD, Lucky A, Liburd OE. (2014). Cotesia congregata (Say), a parasitoid wasp. UF/IFAS Featured Creatures Document EENY-598. (2 October 2017)
  • Deel S. (1999). Tobacco hornworms. Research Link 2000, Carleton College, Northfield, Minnesota, USA. (1 October 2017)
  • del Campo ML, Renwick JAA. 1999. Dependence on host constituents controlling food acceptance by Manduca sexta larvae. Entomologia Experimentalis et Applicata 93: 209-215.
  • del Campo ML, Miles CI, Schroeder FC, Mueller C, Booker R, Renwick JA. 2001. Host recognition by the tobacco hornworm is mediated by a host plant compound. Nature 411: 186-189.
  • Fraser AM, Mechaber WL, Hildebrand JG. 2003. Electroantennographic and behavioral responses of the sphinx moth Manduca sexta to host plant headspace volatiles. Journal of Chemical Ecology 29: 1813-1833.
  • Glendinning JI, Foley C, Loncar I, Rai M. 2009. Induced preference for host plant chemicals in the tobacco hornworm: Contribution of olfaction and taste. Journal of Comparative Physiology A 195: 591-601.
  • Haribal M, Renwick JAA, Attygalle AB, Kiemle D. 2006. A feeding stimulant for Manduca sexta from Solanum surattenses. Journal of Chemical Ecology 32: 2687-2694.
  • Koenig C, Bretschneider A, Heckel DG, Grosse-Wilde E, Hansson BS, Vogel H. 2015. The plastic response of Manduca sexta to host and non-host plants. Insect Biochemistry and Molecular Biology 63: 72-85.
  • Lotts K, Naberhaus T. (2017). Carolina sphinx, Manduca sexta (Linnaeus, 1763). Butterflies and Moths of North America, http://www.butterfliesandmoths.org/ (1 October 2017)
  • Nijhout HF, Williams CM. 1974. Control of moulting and metamorphosis in the tobacco hornworm, Manduca sexta (L.): Growth of the last-instar larva and the decision to pupatae. Journal of Experimental Biology 61: 481-491.
  • Reisenman CE, Riffell JA, Hildebrand JG. 2009. Neuroethology of oviposition behavior in the moth Manduca sexta. International Symposium on Olfaction and Taste 1170: 462-467.
  • Riddiford LM, Hiruma K, Zhou X, Nelson CA. 2003. Insights into the molecular basis of the hormonal control of molting and metamorphosis from Manduca sexta and Drosophila melanogaster. Insect Biochemistry and Molecular Biology 33: 1327-1338.
  • Späthe A, Reinecke A, Olsson SB, Kesavan S, Knaden M, Hansson BS. 2013. Plant species and status-specific odorant blends guide oviposition choice in the moth Manduca sexta. Chemical Senses 38: 147-159.
  • Willott E. (2003). How to sex Manduca larvae and pupae. The University of Arizona. (2 October 2017)

Authors: Morgan A. Byron and Jennifer L. Gillett-Kaufman, Entomology and Nematology Department, University of Florida
Photographs: Lyle J. Buss and James Castner, Entomology and Nematology Department, University of Florida
Web Design: Don Wasik, Jane Medley
Publication Number: EENY-692
Publication Date: October 2017


Biology

Anisakiasis is caused by the ingestion of larvae of several species of ascaridoid nematodes (roundworms), which are sometimes called &ldquoherringworm&rdquo, &ldquocodworm&rdquo, or &ldquosealworm&rdquo, in undercooked marine fish. Known human-infecting anisakid species include members of the Anisakis simplex complex [A. simplex sensu stricto, A. pegreffii, A. berlandi (=A. simplex C)], the Pseudoterranova decipiens complex (P. decipiens sensu stricto, P. azarasi, P. cattani, and others), and the Contracecum osculatum complex. Recent genetic studies have revealed high diversity within these anisakid groups, suggesting additional cryptic species are likely represented in zoonotic infections.

Life Cycle:

Adult stages of anisakid nematodes reside in the stomach of marine mammals, where they are embedded in the mucosa in clusters. Unembryonated eggs produced by adult females are passed in the feces of marine mammals . The eggs become embryonated in water, undergoing two developmental molts , and hatch from the eggs as free-swimming ensheathed third-stage (L3) larvae . These free-swimming larvae are then ingested by crustaceans . The ingested larvae grow within the crustacean hemocoel, and become infective to fish and cephalopod paratenic hosts. After preying upon infected crustaceans, the digested L3 larvae migrate from the paratenic host intestine into the abdominal cavity, and eventually to the tissues of the mesenteries and skeletal muscle. Through predation, tissue-stage L3 larvae can be transmitted among paratenic hosts . Fish and squid maintain L3 larvae that are infective to humans and marine mammals .

When fish or squid containing third-stage larvae are ingested by definitive host marine mammals, the larvae molt twice and develop into adult worms . After ingestion by humans, the anisakid larvae penetrate the gastric and intestinal mucosa, causing the symptoms of anisakiasis .


What are Larvae? (with pictures)

A larva is a juvenile form of an animal that differs substantially in its body morphology and internal organs than the adult organism. For instance, a caterpillar is the larval form of a butterfly. In contrast, juvenile humans are pretty much the same as adult humans, only smaller. A larval stage is common among insects, fish, amphibians, crustaceans, and certain mollusks, echinoderms, annelids, and others. Some species actually evolve into an exclusively larval form and remain there. The process of turning from a larvae into an adult is called metamorphosis.

The larval stage is a stepping stone to adulthood for these animals. There are various evolutionary benefits to having a larval stage: generally, the stage is better optimized for its small size and appetite. This is especially true for animal species that tend to have a "quantity over quality" evolutionary strategy -- in some cases, it would be a waste to produce thousands of adults directly, as many of them would die anyway, and would be more energy-hungry than larval forms. The larval form gives these animals a "trial period" -- a low-energy way to get into the game of living. If the larval form collects enough food, either through its own efforts or with the assistance of adults, it merits graduation to adult form, and usually, the ability to produce its own offspring.

Larva are given different names depending on the animal they are associated with. They often have a fat, worm-like appearance (especially among insects), other times a smaller version of the adult but with important morphological differences. The variation in larval forms is almost as great as the variation in the adult forms they grow into. Most crustacean larvae are called a nauplius, lobster larvae are zoeas, true bug larvae are nymphs, dragonfly larvae are naiads, beetles, bees, and wasps have grubs, flies have maggots, mosquito larvae are known as wigglers, certain mollusk and annelid larvae are called trochophores, butterflies and moths have caterpillars, eel larvae are called leptocephaluses, amphibians have tadpoles, and fish larvae are simply called larvae.

Larvae may either be stationary, almost like a fetus, such as wasp larvae, which subsist on food brought back to the nest by adults. Other larvae are active predators or parasites, like botfly larvae, which infects humans. For insects, larvae are often laid in garbage or stagnant water. In controlling insects, it can be helpful to attack the larval stage rather than the adults themselves. For instance, to eliminate mosquitoes, it is advisable to drain standing pools of water, where the larvae are laid. This strategy has been pursued for decades worldwide. A particularly effective example was during the construction of the Panama Canal, where an effective pest control program almost eliminated the risk of malaria for the canal workers.

Michael is a longtime InfoBloom contributor who specializes in topics relating to paleontology, physics, biology, astronomy, chemistry, and futurism. In addition to being an avid blogger, Michael is particularly passionate about stem cell research, regenerative medicine, and life extension therapies. He has also worked for the Methuselah Foundation, the Singularity Institute for Artificial Intelligence, and the Lifeboat Foundation.

Michael is a longtime InfoBloom contributor who specializes in topics relating to paleontology, physics, biology, astronomy, chemistry, and futurism. In addition to being an avid blogger, Michael is particularly passionate about stem cell research, regenerative medicine, and life extension therapies. He has also worked for the Methuselah Foundation, the Singularity Institute for Artificial Intelligence, and the Lifeboat Foundation.


Many native biological control agents feed on hornworms in North Carolina, and these predators and parasites play an active role in reducing the damage hornworms cause. The most obvious hornworm parasitoids are Cotesia congregata. These wasps lay their eggs inside of first to third instar hornworm larvae. As the caterpillars mature, so do the wasp larvae. The wasp larvae then emerge from the fourth or fifth instar hornworm and pupate in white cocoons on their backs. A parasitized hornworm eats roughly 1/5 that of a non parasitized worm.

This hornworm was parasitized by braconid wasps. Although the white bodies look like “eggs”, they are actually tiny wasp cocoons. Photo: Demetri Tsiolkas

Stilt bug adults and nymphs (Jalysus spinosus) feed on both tobacco budworm and hornworm eggs. Many species of wasps (Polistes spp.) use hornworms and other caterpillars as food for their larvae. Tachinid fly parasitiods (Winthemia spp. and Archytas marmoratus) also attack hornworms, killing them in the pupal stage.

More information


Maggot therapy improves healing in chronic ulcers. [1] In diabetic foot ulcers there is tentative evidence of benefit. [3] A Cochrane review of methods for the debridement of venous leg ulcers found maggot therapy to be broadly as effective as most other methods, but the study also noted that the quality of data was poor. [4]

In 2004, the United States Food and Drug Administration (FDA) cleared maggots from common green bottle fly for use as a "medical device" in the US for the purpose of treatment of: [5]

  • Non-healing necrotic skin and soft tissue wounds
  • Non-healing traumatic or post-surgical wounds

Limitations Edit

The wound must be of a type which can benefit from the application of maggot therapy. A moist, exudating wound with sufficient oxygen supply is a prerequisite. Not all wound-types are suitable: wounds which are dry, or open wounds of body cavities do not provide a good environment for maggots to feed. In some cases it may be possible to make a dry wound suitable for larval therapy by moistening it with saline soaks. [6]

Patients and doctors may find maggots distasteful, although studies have shown that this does not cause patients to refuse the offer of maggot therapy. [7] Maggots can be enclosed in opaque polymer bags to hide them from sight. Dressings must be designed to prevent any maggots from escaping, while allowing air to get to the maggots. [8] Dressings are also designed to minimize the uncomfortable tickling sensation that the maggots often cause. [9]

The maggots have four principal actions:

  • Debridement [10]
  • Disinfection of the wound [11]
  • Stimulation of healing [11]
  • Biofilm inhibition and eradication [12]

Debridement Edit

In maggot therapy, large numbers of small maggots consume necrotic tissue far more precisely than is possible in a normal surgical operation, and can debride a wound in a day or two. The area of a wound's surface is typically increased with the use of maggots due to the undebrided surface not revealing the actual underlying size of the wound. They derive nutrients through a process known as "extracorporeal digestion" by secreting a broad spectrum of proteolytic enzymes [13] that liquefy necrotic tissue, and absorb the semi-liquid result within a few days. In an optimum wound environment maggots molt twice, increasing in length from about 2 mm to about 10 mm, and in girth, within a period of 48–72 hours by ingesting necrotic tissue, leaving a clean wound free of necrotic tissue when they are removed. [14]

Disinfection Edit

Secretions from maggots believed to have broad-spectrum antimicrobial activity include allantoin, urea, phenylacetic acid, phenylacetaldehyde, calcium carbonate, proteolytic enzymes, and many others. [15] In vitro studies have shown that maggots inhibit and destroy a wide range of pathogenic bacteria including methicillin-resistant Staphylococcus aureus (MRSA), group A and B streptococci, and Gram-positive aerobic and anaerobic strains. [16] Other bacteria like Pseudomonas aeruginosa, E. coli or Proteus spp. are not attacked by maggots, and in case of Pseudomonas even the maggots are in danger. [17]

Biology of maggots Edit

Those flies whose larvae feed on dead animals will sometimes lay their eggs on the dead parts (necrotic or gangrenous tissue) of living animals. The infestation by maggots of live animals is called myiasis. Some maggots will feed only on dead tissue, some only on live tissue, and some on live or dead tissue. The flies used most often for the purpose of maggot therapy are blow flies of the Calliphoridae: the blow fly species used most commonly is Lucilia sericata, the common green bottle fly. Another important species, Protophormia terraenovae, is also notable for its feeding secretions, which combat infection by Streptococcus pyogenes and S. pneumoniae. [18]

Written records have documented that maggots have been used since antiquity as a wound treatment. [19] There are reports of the use of maggots for wound healing by Maya, Native Americans, and Aboriginal tribes in Australia. Maggot treatment was reported in Renaissance times. Military physicians observed that soldiers whose wounds had become colonized with maggots experienced significantly less morbidity and mortality than soldiers whose wounds had not become colonized. These physicians included Napoleon’s general surgeon, Baron Dominique Larrey. Larrey reported during France's Egyptian campaign in Syria (1798–1801) that certain species of fly consumed only dead tissue and helped wounds to heal. [18]

Joseph Jones, a ranking Confederate medical officer during the American Civil War, stated:

I have frequently seen neglected wounds . filled with maggots . as far as my experience extends, these worms eat only dead tissues, and do not injure specifically the well parts." The first documented therapeutic use of maggots in the United States is credited to a second Confederate medical officer Dr. J.F. Zacharias, who reported during the American Civil War that, "Maggots . in a single day would clean a wound much better than any agents we had at our command . I am sure I saved many lives by their use.

He recorded a high survival rate in patients he treated with maggots. [20]

During World War I, orthopedic surgeon William S. Baer recorded the case of a soldier left for several days on the battlefield who had sustained compound fractures of the femur and large flesh wounds. The soldier arrived at the hospital with maggots infesting his wounds but had no fever or other signs of infection and survived his injuries, which would normally have been fatal. After the war, Baer began using maggot therapy at Boston Children's Hospital in Massachusetts. [21] [22] : 169–71

There were reports that American prisoners of war of the Japanese in World War II resorted to maggot therapy to treat severe wounds. [23] [24]

A survey of US Army doctors published in 2013 found that 10% of them had used maggot therapy. [25]

In January 2004, the FDA granted permission to produce and market maggots for use in humans or animals as a prescription-only medical device for the following indications: "For debriding non-healing necrotic skin and soft tissue wounds, including pressure ulcers, venous stasis ulcers, neuropathic foot ulcers, and non-healing traumatic or post-surgical wounds." [26] [27]

The use of maggots to clean dead tissue from animal wounds is part of folk medicine in many parts of the world. [28] It is particularly helpful with chronic osteomyelitis, chronic ulcers, and other pus-producing infections that are frequently caused by chafing due to work equipment. [ citation needed ] Maggot therapy for horses in the United States was re-introduced after a study published in 2003 by veterinarian Dr. Scott Morrison. This therapy is used in horses for conditions such as osteomyelitis secondary to laminitis, sub-solar abscesses leading to osteomyelitis, post-surgical treatment of street-nail procedure for puncture wounds infecting the navicular bursa, canker, non-healing ulcers on the frog, and post-surgical site cleaning for keratoma removal. [29]

However, there have not been many case studies done with maggot debridement therapy on animals, and as such it can be difficult to accurately assess how successful it is. [30]


What kind of larvae are these? - Biology

The household casebearer, Phereoeca uterella, is a moth in the Tineidae family of Lepidoptera. Many species in this family are casebearers and a few are indoor pests of hair fibers, woolens, silks, felt and similar materials. Most people know this species by the name plaster bagworm. However, bagworms are moths in the family Psychidae. Perhaps for this reason, the accepted common name of Phereoeca uterella is now listed as the household casebearer, instead of plaster bagworm (Bosik JJ, et al. 1997).

Figure 1. A larva of the household casebearer, Phereoeca uterella Walsingham, which is partially emerged from its case and using its true legs to walk on a surface. Photograph by Lyle J. Buss, University of Florida.

The cases are constructed by the larval (caterpillar) stage and often attract attention when found in homes. However, we usually see only the empty larval or pupal cases of the household casebearer on walls of houses in south and central Florida.

Taxonomy (Back to Top)

The first record of this species came from Lord Walsingham in 1897 (Busck, 1933). However, the specimens that he collected from the Virgin Islands were misidentified.

In 1933, August Busck proposed the name Tineola walsinghami for the Virgin Island insects of Walsingham. The same year Kea wrote about the food habits of the species present in Florida, using the name given by Walsingham (Tineola uterella). After a while, the species in the peninsula was recognized as Tineola walsinghami. In 1956, Hinton and Bradley described the new genus Phereoeca, in order to separate the true Tineola from this and other species of flat case-bearing moths.

Finally, an early synonym established by Meyrick was recognized as the most appropriate name, and the species was named Phereoeca dubitatrix (Meyrick 1932). However, another name change occurred and the current official common and scientific names for this species are the household casebearer, Phereoeca uterella Walsingham.

Distribution (Back to Top)

The household casebearer, Phereoeca uterella, requires high humidity to complete its development, a limiting factor for its dispersion throughout the rest of the country. Hetrick (1957) observed the insect in many parts of Florida and Louisiana, as well as USDA records of the household casebearer from Mississippi and North Carolina. He also assumed that this species might be present in the coastal areas of Alabama, Georgia, South Carolina, Texas and Virginia. However, proper identification by a specialist is advised, because case-bearing species other than Phereoeca uterella might be in those states.

In South America, Phereoeca uterella Walsingham is known to be present in Brazil (state of Para) and Guyana.

Another related species of case-bearing moths is Praececodes atomosella (tecophora) (Walker 1863). It was found in Gainesville, Florida, and has been recorded as present in the southern USA, Hawaii, Mexico, Bermuda, Brazil, Peru, Venezuela, Europe, Africa, Malaya, Australia and other localities. It is possible that records of Phereoeca uterella might be misidentified as this species or vice versa.

Due to the active international exchange of goods, other case-bearing moths may occur in Florida in the future. For example, Phereoeca allutella (Rebel) has been recorded in Hawaii, Panama, Canary Islands, Madeira, Sierra Leone, Seychelles, Sri Lanka, India, Java and Samoa.

Description (Back to Top)

Egg: After mating, females lay their eggs on crevices and the junction of walls and floors, cementing them on debris. Two hundred eggs may be oviposited by a single female over a period of a week, after which she dies. Eggs are soft, pale bluish, and about 0.4 mm in diameter.

Larva: The larva is not usually seen by most people. The case that it carries around wherever it feeds is what is immediately recognized. It can be found under spiderwebs, in bathrooms, bedrooms and garages. Cases can be found on wool rugs and wool carpets, hanging on curtains, or underneath buildings, hanging from subflooring, joists, sills and foundations on the exterior of buildings in shaded places, under farm sheds, under lawn furniture, on stored farm machinery and on tree trunks.

The larval case is a slender, flat, fusiform or spindle-shaped case which resembles a pumpkin seed. It is silk-lined inside and open at both ends. Most of the biology described here was taken from Aiello's (1979) description of Phereoeca allutella, a closely related case-bearing moth species from Panama. Specific information of Phereoeca uterella biology is limited.

The case is constructed by the earliest larval stage (1st instar) before it hatches, and is enlarged by each successive instar. In constructing the case, the larva secretes silk to build an arch attached at both ends to the substrate. Very small particles of sand, soil, iron rust, insect droppings, arthropod remains, hairs and other fibers are added on the outside. The inside of the arch is lined exclusively by silk, and is gradually extended to form a tunnel, while the larva stays inside. The tunnel is closed beneath by the larva to form a tube free from the substrate, and open at both ends. After the first case is completed, the larva starts moving around, pulling its case behind. With each molt, the larva enlarges its case. Later cases are flattened and widest in the middle, allowing the larva to turn around inside. A fully developed larva has a case 8 to 14 mm long and 3 to 5 mm wide.

Figure 2. Case of household casebearer, Phereoeca uterella Walsingham. Photograph by Lyle J. Buss, University of Florida.

Both ends of the case are identical, and are used by the larva to hide. When disturbed, it encloses itself in the case by pulling the bottom side up. This closing mechanism is very difficult to open from the outside.

The fully developed larva is about 7 mm long. It has a dark brown head, and the rest of the body is white, except for the lateral and dorsal plates on the three thoracic segments close to the head, which are hardened and dark. Aiello (1979) believes the plates protect the larva from natural enemies when it reaches out of its case for locomotion.

The larva has three pair of well-developed, brown legs. The ventral prolegs are white, and are located on abdominal segments 3 to 6 and 10. At the tip of each proleg there is an ellipse formed by 23 to 25 very small crochets (a small hook). The anterior crochets are bigger and broader than posterior ones by one third, which is a good detail for identification. The crochets are used to walk inside the case, and also to grab the case when the larva pulls its head and thorax out and uses its true legs to walk on the floor or walls.

Pupa: Pupation occurs inside the case. The larva walks up a vertical surface and attaches the case at both ends with silk. One end of the case is then modified. The larva cuts a short slit along both edges to make that end flatter, which acts as a valve. Before eclosion the pupa pulls itself halfway through the valve. The new moth emerges around noon, leaving the pupal case exposed on the outer case.

Adult: Adult females have a wing span 10 to 13 mm long. They are gray with up to four spots on the fore wings, and a brush of long, lighter gray hair-like scales along the posterior margin of the hind wings. Males are smaller (wing span: 7 to 9 mm) and thinner than the female, with a less distinctive wing pattern.

Figure 3. Adult female household casebearer, Phereoeca uterella Walsingham. Photograph by Lyle J. Buss, University of Florida.

Figure 4. Adult male household casebearer, Phereoeca uterella Walsingham. Photograph by Juan A. Villanueva-Jiménez, University of Florida.

The heads of both sexes are uniformly clothed with dense, rough hairs. There are two pairs of buccal appendages called palps. The maxillary palps are smaller than the labial palps, and are folded inwards. The labial palps extend a little beyond the head vestiture (dense covering of hairs). The remaining mouth parts are reduced and adults do not feed. The antennae are filiform (threadlike), as long as the wings, and are held back over the body. The compound eyes are prominent.

Figure 5. Head of adult household casebearer, Phereoeca uterella Walsingham. Photograph by Juan A. Villanueva-Jiménez, University of Florida.

Wing venation is very important for genera identification, and was described by Hinton and Bradley in 1956. Adults at rest hold their wings tented over the body. They fly fairly well, but usually rest on walls, floor edges, or on webs of house spiders (theridiids) (Aiello 1979).

Life Cycle (Back to Top)

At non-air-conditioned room temperature in Panama, the life cycle of Phereoeca uterella (a close relative of Phereoeca dubitatrix) was reported by Aiello (1979) as follows:

Eggs require more than 10 days to hatch. There are six to seven larval instars that require about 50 days to mature. They remain in the pupal stage an average of 15.6 days (range of 11 to 23 days). The entire cycle from egg to adult averages 74.2 days (62 to 86 days). Aiello (1979) indicates that the number of instars may vary among individuals of both sexes.

Economic Significance (Back to Top)

Hetrick (1957) found that the most common and abundant food of the household casebearer in Florida is old spider webs, consumed in large quantities. Webs of insects such as booklice (Psocoptera) and webspinners (Embioptera) from tree trunks were also suitable food. Old cases of its own species were chewed as well. Kea (1933) could not observe this insect feeding on dried insects in the laboratory, even though small portions of dried insects were found attached to its case. Furthermore, household casebearer larvae did not eat cotton products offered by Kea. But when woolen threads and woolen cloth were offered to the larvae "they ate eagerly". Watson (1939) corroborated the preference of Phereoeca uterella for woolen goods of all kinds. Aiello (1979) succeeded in rearing specimens of the related species Phereoeca allutella by offering them dead mosquitoes and her own hair.

Management (Back to Top)

Due to its food habits the household casebearer is a potential household pest. However, regular cleaning practices, increased use of air conditioning in houses, and reduced number of woolen goods in this part of the country, along with pesticide application in cracks and crevices for household pest control, have decreased the incidence of the household casebearer. Manual picking or vacuuming of cases and spider web removal should be enough to keep this species under control.

A braconid wasp, Apanteles carpatus (Say), parasitizes larvae of case-bearing moths, killing the larva before pupation. In Florida, this braconid and an ichneumonid wasp, Lymeon orbum (Say), were reared from the household casebearer (Hetrick 1957).

Selected References (Back to Top)

  • Aiello A. 1979. Life history and behavior of the case-bearer Phereoeca allutella (Lepidoptera: Tineidae). Psyche 86: 125-136.
  • Arnett Jr RH. 2000. American Insects: A Handbook of the Insects of America North of Mexico. CRC Press. Boca Raton. 1003 pp.
  • Borror DJ, Triplehorn CA, Johnson NF. 1989. An Introduction to the Study of Insects. Harcourt Brace Jovanovich College Publishers. New York. 875 pp.
  • Bosik JJ, et al. 1997. Common Names of Insects & Related Organisms. Entomological Society of America. 232 pp.
  • Busck A. 1933. Microlepidoptera of Cuba. Entomologica Americana 13: 151-203.
  • Creighton JT. 1954. Household Pests. Bulletin No. 156, new series. State of Florida, Department of Agriculture, Tallahassee. pp. 39-43.
  • Hetrick LA. 1957. Some observations on the plaster bagworm, Tineola walsinghami Busck (Lepidoptera: Tineidae). Florida Entomologist 40: 145-146.
  • Hinton HE. 1956. The larvae of the species of Tineidae of economic importance. Bulletin of Entomological Research 47: 251-346.
  • Hinton HE, Bradley JD. 1956. Observations on species of Lepidoptera infesting stored products. XVI: Two new genera of clothes moths (Tineidae). The Entomologist 89: 42-47.
  • Kea JW. 1933. Food habits of Tineola uterella. Florida Entomologist 17: 66.
  • Watson JR. 1939. Control of four household insects. University of Florida, Agricultural Experiment Station Bulletin 536.
  • Watson JR. 1946. Control of three household insects. University of Florida, Agricultural Experiment Station Bulletin 619.

Authors: Juan A. Villanueva-Jiménez and Thomas R. Fasulo, University of Florida
Photographs: Juan A. Villanueva-Jiménez and Lyle J. Buss, University of Florida
Web Design: Don Wasik, Jane Medley
Publication Number: EENY-3
Publication Date: September 1996. Latest revision: April 2017. Reviewed: June 2020.

An Equal Opportunity Institution
Featured Creatures Editor and Coordinator: Dr. Elena Rhodes, University of Florida


Complete Metamorphosis Examples

Complete metamorphosis examples cover a wide range of insect orders. The majority of holometabolous insects have wings, although there are groups which feature wingless adults. The best-known holometabolous insects are those included in the orders Lepidoptera (butterflies and moths) and Coleoptera (beetles).

Other orders that feature holometaboly are Diptera (flies), Neuroptera (including lacewings, alderflies and mayflies), Siphonaptera (fleas), and Hymenoptera (ants, bees and wasps). Those species that do not undergo complete metamorphosis and present as nymphs (using the processes involved in incomplete metamorphosis) have their own orders.

The production of wings is an expensive process in terms of energy, and the production of a female adult which much resembles the larval form and without wings does, on occasion, occur. This phenomenon is called neoteny or juvenilization. Examples are the female trilobite beetle or bagworm moth. However, neotenic insects all go through the four stages of complete metamorphosis.

What Are Hypermetamorphic Insects?

On the other end of the scale, some insects have very distinct-looking instar forms in the larval stage. These additional changes within the normal complete metamorphosis process are found in hypermetamorphic insects of the Strepsiptera orders, as well as in various parasitic wasp, beetle, fly, and mantis-fly species. In relation to non-hypermetamorphic insects, the earliest versions of parasitic instars are very mobile and very small, making it much easier for them to find hosts.


Eastern Tent Caterpillar

The eastern tent caterpillar, Malacosoma americanum, is a pest native to North America. Populations fluctuate from year to year, with outbreaks occurring every several years. Defoliation of trees, building of unsightly silken nests in trees, and wandering caterpillars crawling over plants, walkways, and roads cause this insect to be a pest in the late spring and early summer. Eastern tent caterpillar nests are commonly found on wild cherry, apple, and crabapple, but may be found on hawthorn, maple, cherry, peach, pear and plum as well.

Figure 1. An eastern tent caterpillar.

While tent caterpillars can nearly defoliate a tree when numerous, the tree will usually recover and put out a new crop of leaves. In the landscape, however, nests can become an eyesore, particularly when exposed by excessive defoliation. The silken nests are built in the crotches of limbs and can become quite large.

Larvae cause considerable concern when they begin to wander to protected places to pupate. Frequently they are seen crawling on other types of plants, walkways, and storage buildings. They are a nuisance and can create a mess when they are squashed on driveways, sidewalks, and patios. But keep in mind that no additional feeding or damage is done by the wandering caterpillars.

Insecticides are generally ineffective against mature larvae.

Eastern tent caterpillar nests are frequently confused with fall webworm nests. Unlike the tent caterpillar, fall webworm nests are located at the ends of the branches and their loosely woven webs enclose foliage while the tents of the eastern tent caterpillar do not. While there may be some overlap, fall webworm generally occurs later in the season.

Biology

The eastern tent caterpillar overwinters as an egg, within an egg mass of 150 to 400 eggs. These masses are covered with a shiny, black varnish-like material and encircle branches that are about pencil-size or smaller in diameter.

Figure 2. Eastern tent caterpillar egg masses are wrapped around small twigs.

The caterpillars hatch about the time the buds begin to open, usually in early March. These insects are social caterpillars from one egg mass stay together and spin a silken tent in a crotch of a tree. Caterpillars from two or more egg masses may unite to form one large colony. During the heat of the day or rainy weather, the caterpillars remain within the tent. They emerge to feed on leaves in the early morning, evening, or at night when it is not too cold.

Figure 3. An eastern tent caterpillar nest.

The larvae are hairy caterpillars, black with a white stripe down the back, brown and yellow lines along the sides, and a row of oval blue spots on the sides. As the larvae feed on the foliage, they increase the size of the web until it is a foot or more in length. In 4 to 6 weeks the caterpillars are full grown and 2 to 2-1/2 inches long. At this time, they begin to wander away individually from the nest in search of protected areas to spin a cocoon. The cocoon is about 1 inch long and made of closely woven white or yellowish silk and is attached to other objects by a few coarser threads.

Figure 4. An adult male eastern tent moth.

The adult moth emerges from the cocoon about 3 weeks later. The moth is reddish-brown with two pale stripes running diagonally across each forewing. Moths mate and females begin to lay eggs on small branches. The eggs will hatch next spring. There is just one generation per year.

Management

  • Natural enemies play an important role in reducing eastern tent caterpillar numbers in most years. Caterpillars are frequently parasitized by various tiny braconid, ichneumonid, and chalcid wasps. Several predators and a few diseases also help to regulate their populations. This, in part, accounts for the fluctuating population levels from year to year.
  • Prevention and early control is important. Removal and destruction of the egg masses from ornamentals and fruit trees during winter greatly reduces the problem next spring. In the early spring, small tents can be removed and destroyed by hand. Larger tents may be pruned out and destroyed or removed by winding the nest upon the end of a stick. Burning the tents out with a torch is not recommended since this can easily damage the tree.
  • Young caterpillars can be killed by applying an insecticide containing Bacillus thuringiensis var kurstaki. Other insecticides include carbaryl, and malathion. Larvae within the tents are protected beneath the webbing and are more difficult to kill with an insecticide.

CAUTION! Pesticide recommendations in this publication are registered for use in Kentucky, USA ONLY! The use of some products may not be legal in your state or country. Please check with your local county agent or regulatory official before using any pesticide mentioned in this publication.

Of course, ALWAYS READ AND FOLLOW LABEL DIRECTIONS FOR SAFE USE OF ANY PESTICIDE!


Who needs a body? Not these larvae, which are basically swimming heads

Schizocardium californicum as a larva. In the larval stage, S. californicum is little more than a swimming head. Credit: Paul Gonzalez, Hopkins Marine Station

Graduate student Paul Gonzalez at Stanford University's Hopkins Marine Station recently became a hunter, breeder and farmer of a rare marine worm, all to fill in a considerable gap in our understanding of how animals develop. He knew that some animals go through a long larval stage, a developmental strategy known as indirect development, and this rare worm was his chance to better understand that process.

What Gonzalez and his colleagues found was that the worms go through a prolonged phase with little more than head. This work, published in the Dec. 8 issue of Current Biology, suggests that many animals in the ocean likely share this trunk-less stage, and it may even shed light on the biological development of early animals.

"Indirect development is the most prevalent developmental strategy of marine invertebrates and life evolved in the ocean," said Chris Lowe, senior author of the paper and associate professor of biology. "This means the earliest animals probably used these kinds of strategies to develop into adults."

Most research animals commonly found in labs, such as mice, zebrafish and the worm C. elegans, are direct developers, species that don't go through a distinct larval stage. To understand how indirect developers differ from these, Gonzalez needed to study an indirect developer that was very closely related to a well-studied direct developer.

His best bet was a group of marine invertebrates called Hemichordata because there is already a wealth of molecular developmental work done on direct developers in this group. A flaw in this plan was that the indirect developers in this phylum were uncommon in areas near the station.

Undeterred, Gonzalez poured through marine faunal surveys until a 1994 study gave him his big break: Schizocardium californicum, a species of acorn worm and indirect developer in the Hemichordata phylum, was once in Morro Bay, only two hours away.

Through contacting the researchers from that decades-old paper, Gonzalez obtained the exact coordinates of the worms. Once there, he pulled on a wet suit, readied his shovel and began his hunt for the odd-looking ocean-dwellers.

Schizocardium californicum as a larva, juvenile and adult. In the larval stage, S. californicum is little more than a swimming head. Credit: Paul Gonzalez and Chris Patton, Hopkins Marine Statio

Diversifying the study of diversity

Direct developers are more often used in research largely for reasons of practicality.

"Terrestrial, direct developing species develop fast, their life cycle is simple and they are easy to rear in the lab," said Gonzalez, who was lead author of the paper.

By comparison, indirect developers develop slowly, have a long larval stage, and their larvae are difficult to feed and maintain in captivity. The reproductive adults are also challenging to keep in the lab and, as Gonzalez has shown, collecting them can be an arduous process. However, the relative ease of studying direct developers has made for a lack of diversity in what scientists know about evolution and development, Gonzalez said.

"By selecting convenient species, we select a non-random sample of animal diversity, running the risk of missing interesting things," he said. "That's what brought me to the Lowe lab. We specialize in asking cool evolutionary questions using developmental biology and molecular genetics, and we're not afraid to start from scratch and work on animals that no one has worked with before."

After spending months perfecting the rearing and breeding techniques needed to study these worms, the researchers were eventually able to sequence the RNA from various stages of the worm's development. They did this in order to see where specific genes are turned on or off in an embryo.

Paul Gonzalez, graduate student at Stanford University's Hopkins Marine Station, collecting worms in Morro Bay, California. Credit: Paul Gonzalez, Hopkins Marine Station

They found that in the worms, activity of certain genes that would lead to the development of a trunk are delayed. So, during the larval stage, the worms are basically swimming heads.

"When you look at a larva, it's like you're looking at an acorn worm that decided to delay development of its trunk, inflate its body to be balloon-shaped and float around in the plankton to feed on delicious algae," said Gonzalez. "Delayed trunk development is probably very important to evolve a body shape that is different from that of a worm, and more suitable for life in the water column."

As they continue to grow, the acorn worms eventually undergo a metamorphosis to their adult body plan. At this point, the genes that regulate the development of the trunk activate and the worms begin to develop the long body found in adults, which eventually grows to about 40 cm (15.8 inches) over the span of several years.

Even with such a fascinating result, this research is only the beginning of the Lowe lab's examination of indirect developers. These worms will never tell us about human diseases, unlike work with stem cells or mice, but they could reveal the intricacies of how life works for many organisms beyond the model species that we've studied so heavily. They may also show us how life in general came to be what it is today.

"Given how pervasive larvae are in the animal world, we understand very little about this critical phase in animal development," said Lowe. "These are not the kind of species you want to pick if you want deep, mechanistic insights into developmental biology. But, if your goal is to understand how animals have evolved, then you cannot avoid using these species."

Next, the researchers want to figure out how the acorn worm body development delay happens. They also have begun to sequence the genome of S. californicum.

Kevin R. Uhlinger, lab manager in the Lowe lab at Hopkins Marine Station, is also a co-author of this paper. Chris Lowe is also a member of Stanford Bio-X and the Stanford Neurosciences Institute.