Motobdella montezuma

Motobdella montezuma
Scientific classification
Kingdom: Animalia
Phylum: Annelida
Class: Clitellata
Subclass: Hirudinea
Family: Erpobdellidae
Genus: Motobdella
Species: M. montezuma
Binomial name
Motobdella montezuma
(Davies, Singhal & Blinn, 1985) [1]
Synonyms [2]

Erpobdella montezuma Davies, Singhal & Blinn, 1985

Motobdella montezuma is a species of leech which is only found in Montezuma Well, central Arizona, United States. It is a nocturnal pelagic predator that feeds almost exclusively on the endemic amphipod Hyalella montezuma, which it detects using passive sonar and swallows whole.

Description

Adults of M. montezuma may reach a length of 71 mm (2.8 in) including the suckers at the front and rear.[3]

Distribution

M. montezuma is closely related to the genus Erpobdella,[4] which includes species that are widespread across North America from Alaska to Mexico.[5] However, M. montezuma is only known to occur in a single pool, Montezuma Well, in the Montezuma Castle National Monument in Yavapai County, Arizona.[6]

Ecology

Montezuma Well due to a high carbon dioxide level in the water is unable to support a population of fish, leaving an ecological niche of open-water predator free. Although there are a number of species of invertebrates living in the well, the diet of M. montezuma consists almost entirely of the endemic amphipod Hyalella montezuma.[6]

Behavior

M. montezuma is nocturnal, resting at the bottom of the well during the day, when predatory waterfowl are present.[7] As night falls, the leeches swim towards the surface and hunt amphipods near the surface; this is the only instance of a leech hunting in open water.[7] Prey are detected by passive sonar, and swallowed whole. This pattern of diel vertical migration by a leech is only known to occur in Montezuma Well.[7]

Life cycle

Like many other leeches, M. montezuma is hermaphroditic. Sexual reproduction results in two individuals fertilizing each other, and the resulting eggs are placed in a nutrient-filled cocoon. The cocoon is placed deep enough to avoid the attention of ducks and other predators, and the eggs hatch into self-sufficient juveniles.[7]

References

  1. "Motobdella montezuma". Integrated Taxonomic Information System.
  2. "Erpobdellidae". Texas A&M University. Retrieved April 19, 2010.
  3. Fredric R. Govedich, Dean W. Blinn, Paul Keim & Ronald W. Davies (1998). "Phylogenetic relationships of three genera of Erpobdellidae (Hirudinoidea), with a description of a new genus, Motobdella, and species, Motobdella sedonensis". Canadian Journal of Zoology 76 (12): 2164–2171. doi:10.1139/cjz-76-12-2164.
  4. James H. Thorp & Alan P. Covich (2001). Ecology and classification of North American freshwater invertebrates (2nd ed.). Academic Press. ISBN 978-0-12-690647-9.
  5. Roy T. Sawyer (1970). "Observations on the natural history and behavior of Erpobdella punctata (Leidy) (Annelida: Hirudinea)". American Midland Naturalist 83 (1): 65–80. doi:10.2307/2424006.
  6. 6.0 6.1 Dean W. Blinn, Ronald W. Davis & Behrooz Dehdashti. "Specialized open water feeding by the leech, Erpodbella montezuma (Hirudinea)". Northern Arizona University. Retrieved April 19, 2010.
  7. 7.0 7.1 7.2 7.3 Fredric R. Govedich & Bonnie A. Bain (2005). "All about the leeches of Montezuma Well". National Park Service. Retrieved April 19, 2010.