Lampetra appendix

Geographic Range

American brook lamprey , Lampetra appendix , are limited on the northern end to Ontario and Quebec in Canada, south to North Carolina, Alabama, and Mississippi in the United States. The eastern limit is the east coast, from North Carolina to as far north as New Hampshire. The western limit is from Arkansas to Minnesota.

• Biogeographic Regions
• nearctic nearctic
  • native native

Habitat

American brook lamprey larvae typically reside in soft sediments within shallow, slow moving, fresh water streams. A suitable speed of water movement is roughly 5 centimeters per second, while depths are frequently less than 50 centimeters. The soft sediment often consists of fine sand and silt, although coarse sand and gravel are sometimes present in small amounts.

Adult habitats are typically gravel-sand riffles, creeks, or small to medium rivers with a strong water flow.

• Habitat Regions
• temperate temperate
• freshwater freshwater

• Aquatic Biomes
• benthic benthic
• lakes and ponds
• rivers and streams

Physical Description

Larval American brook lamprey, also called an ammocoete, hatch at about 2.6mm, but will continue to grow until metamorphosis, averaging 38mm at age 1. It is dark brown on the dorsal and lateral surfaces, and yellow-brown on the ventral surface.

Adult American brook lamprey are approximately 10.3 - 21.7cm long, 2.8 - 16.2g wet, with gray to black coloration on the dorsal and dorsal-lateral surfaces, and tan to gray white on the ventral and ventral-lateral surfaces. No distinction exists between male and female individuals.

Eggs are sphere shaped, adhesive, and sink to the bottom of the water. Color can range from pale yellow to light green.

As is characteristic with lampreys, this species has cartilage, as opposed to bones, does not possess jaws, scales, or paired fins, and has one nostril and seven pairs of rounded gill slits. This species possesses a dorsal fin, distinctly separated into two parts and with a black stripe at its base, a mouth disk narrower than the head, and teeth in a cluster pattern on the oral disc, as opposed to in rows. The caudal fin is simple and rounded.

• Other Physical Features
• ectothermic ectothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Development

American brook lamprey larvae hatch in the late spring to early summer, 20 to 22 days after eggs are fertilized. American brook Lamprey begin to undergo metamorphosis in the late summer, after a minimum of 4.5 years in the larval stage, but perhaps after more years. During metamorphosis, the filter feeding mechanisms become suction disks with teeth, and the eyes become fully functional. Metamorphosis is complete in the spring, when adults will begin breeding.

• Development - Life Cycle
• metamorphosis metamorphosis
• diapause diapause

Reproduction

Female American brook lamprey build nests, typically around 16cm in diameter, and use their oral disc to attach to a rock at the upstream end of their nesting site. The male uses his oral disk to attach to the female's head, then wraps his tail around her body so that their urogenital regions are in close proximity. The male contracts his body to assist the female in extrusion of the eggs. Both individuals vibrate vigorously for some seconds before releasing their gametes, serving to partially bury the fertilized eggs.

Multiple adult pairs may congregate to one location when spawning, with a record of 14 spawning lampreys found in one nest.

• Mating System
• monogamous monogamous

American brook lamprey larvae at a minimum of 4.5 years of age begin metamorphosis in late summer, and are fully developed adults and begin to spawn in spring, dying soon after. Per female, more than 1600 eggs are laid in nests in gravel-sand riffles or small to medium rivers, and then may run with the strong flow of the water. With the proper conditions, eggs hatch in 20 to 22 days, producing the larval lamprey.

• Key Reproductive Features
• semelparous semelparous
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• induced ovulation induced ovulation
• fertilization fertilization
  • external external
• broadcast (group) spawning
• oviparous oviparous

Parental involvement ceases after reproduction. When larvae hatch from eggs, parents are often deceased.

• Parental Investment
• precocial precocial

Lifespan/Longevity

American brook lamprey spend at least 4.5 years in the larval stage before beginning metamorphosis, although they may wait longer. Adults do not feed, existing solely to spawn, and will die approximately six months after metamorphosis.

Behavior

American brook lamprey larvae bury themselves in soft sediment, exposing their heads to filter feed. After 4.5 years or more, larvae begin to undergo metamorphosis, and once complete the adults do not feed, existing solely to spawn.

• Key Behaviors
• natatorial natatorial
• motile motile
• sedentary sedentary

Communication and Perception

Larval American brook lampreys can detect light and dark through eye spots, which develop into fully functional eyes during metamorphosis. An amount of chemo-sensory ability is afforded by the lone nostril.

• Communication Channels
• tactile tactile

• Other Communication Modes
• vibrations vibrations

• Perception Channels
• visual visual
• tactile tactile
• chemical chemical

Food Habits

American brook lamprey larvae feed by burying all of their body besides their head, and filtering organic material from the water, consuming a diet largely consisting of diatoms and detritus. Diatoms, however, contribute little to the diet and remain largely undigested, and larval lamprey have been observed healthily consuming diets composed entirely of detritus.

The adult stage lamprey do not feed.

• Primary Diet
• herbivore herbivore
  • algivore
• detritivore detritivore

• Plant Foods
• algae

• Other Foods
• detritus detritus
• microbes

• Foraging Behavior
• filter-feeding filter-feeding

Predation

Larval and adult American brook lamprey can easily become prey for muskellunge, walleyes, and smallmouth bass. The burying behavior demonstrated by larvae of this species may exist as one mechanism to help combat predation.

Economic Importance for Humans: Positive

Ammocoetes, the larval stage of American brook lamprey, were sold extensively as bait in Canada in the mid 20th century.

Conservation Status

While not currently listed by conservation sites, American brook lamprey populations have been reduced or even eliminated from a significant number of streams. The most significant losses are those at the edges of their range.

The major source of concern for American brook lamprey populations is alterations of streams and waterways which served as habitat. This includes removal of suitable spawning area, as well those alterations that affect detritus availability, including production and processing of detritus, as well as delivery of detritus.

Other Comments

American brook lamprey are also known as Lethenteron appendix , Petromyzon appendix , Petromyzon lamottenii , and Lampetra wilderi

Additional Links

Encyclopedia of Life

Contributors

Curtis Gaul (author), Minnesota State University Mankato, Robert Sorensen (editor), Minnesota State University, Mankato, Tanya Dewey (editor), University of Michigan-Ann Arbor.

References

Eschmeyer, W., R. Fricke, R. van der Laan. 2017. "Catalog of Fishes" (On-line). California Academy of Sciences. Accessed April 05, 2017 at http://researcharchive.calacademy.org/research/ichthyology/catalog/fishcatmain.asp .

Hammerson, G. 2012. "NatureServe Explorer" (On-line). Accessed February 13, 2017 at http://explorer.natureserve.org/servlet/NatureServe?searchName=Lampetra+appendix .

Mundahl, N., C. Erickson, M. Johnston, G. Sayeed, S. Taubel. 2005. Diet, feeding rate, and assimilation efficiency of American brook lamprey. Environmental Biology of Fishes , 72: 67-72. Accessed February 13, 2017 at http://link.springer.com/article/10.1007%2Fs10641-004-6591-1 .

Mundahl, N., G. Sayeed, S. Taubel, C. Erickson, A. Zalatel, J. Cousins. 2006. Densities and Habitat of American Brook Lamprey (Lampetra appendix) Larvae in Minnesota. The American Midland Naturalist , 156/1: 11-22. Accessed February 13, 2017 at http://www.bioone.org/doi/abs/10.1674/0003-0031(2006)156%5b11:DAHOAB%5d2.0.CO;2 .

Page, L., B. Burr. 2016. "Lethenteron Appenidx, American brook lamprey" (On-line). Fishbase. Accessed April 05, 2017 at http://www.fishbase.se/summary/2521 .

Illinois Department of Natural Resources. American Brook Lamprey. www.dnr.illinois.gov: Biodiversity of Illinois. 2016. Accessed February 13, 2017 at https://www.dnr.illinois.gov/education/CDIndex/AmBrookLamp.pdf .

Massachusetts Division of Fisheries & Wildlife. American Brook Lamprey. www.nhesp.org: Natural Heritage Endangered Species Program. 2008. Accessed April 19, 2017 at http://www.mass.gov/eea/docs/dfg/nhesp/species-and-conservation/nhfacts/lampetra-appendix.pdf .

University of Michigan Museum of Zoology. 2017. "Lampetra appendix (DeKay); AMERICAN BROOK LAMPREY." (On-line). U-M Library Digital Collections. Accessed February 13, 2017 at http://quod.lib.umich.edu/f/fish5ic/x-006/006 .