Featured Research

from universities, journals, and other organizations

New fish species offers literal take on 'hooking up'

Date:
September 27, 2012
Source:
North Carolina State University
Summary:
A new species of freshwater fish has several interesting -- and perhaps cringe-inducing -- characteristics, including a series of four hooks on the male genitalia.

A magnified view of the four hooked genitalia of the newly identified fish species Gambusia quadruncus.
Credit: Image courtesy of North Carolina State University

Fishing hooks aren't the only hooks found in east-central Mexican waters. A new species of freshwater fish described by a North Carolina State University researcher has several interesting -- and perhaps cringe-inducing -- characteristics, including a series of four hooks on the male genitalia.

Related Articles


Females of the new species -- the llanos mosquitofish, or Gambusia quadruncus -- also have distinguishing characteristics, including a colorful anal spot.

A paper describing the new species, which lives in a diversity hotspot and seemingly branched off from its closest relative more than one million years ago, appears in the Journal of Fish Biology.

Dr. Brian Langerhans, assistant professor of biology at NC State and the lead author of the paper, says that these interesting characteristics may play important roles in mating control and success.

While more research is needed, Langerhans says that four-hooked genitalia on males can serve a purpose when females attempt to block or restrict mating attempts.

"Typically, reproduction is more costly in females, so females favor ways of reducing mating with 'lower quality' males," Langerhans says, "but reproduction is cheap in males and so selection favors ways of mating with as many females as possible. In Gambusia, some females, including G. quadruncus, have evolved modifications that appear to function as a blocking device -- essentially a big ball of tissue blocking most of the genital pore -- restricting entry of the male's gonopodial tip. Thus, the female would have to behaviorally allow the male to mate or the male would have to evolve a counter response to avoid this problem."

The four-hooked genitalia could be that counter-response, Langerhans says.

"Having four hooks on the gonopodium may provide a means of overcoming female resistance, latching on to the gonopore and transferring sperm in a manner that facilitates effective sperm transfer. Or it may serve to stimulate the female in a manner that causes responses in the female that facilitate effective sperm transfer," Langerhans says.

Somewhat similarly, the colorful anal spot on females appears to serve as a signal that only certain males are desired for mating.

"The differing, species-specific female anal spots appear to influence male mating behavior by signaling the location of the gonopore to the male, sometimes indicating the reproductive status of the female, and distinguishing fish of their own species from fish of other species to reduce costly cross-breeding, which can result in fish with reduced fitness," Langerhans says. "So it may be that G. quadruncus evolved different anal spots to help reduce interspecies matings and possible formation of hybrids."


Story Source:

The above story is based on materials provided by North Carolina State University. Note: Materials may be edited for content and length.


Journal Reference:

  1. R. B. Langerhans, M. E. Gifford, O. Domínguez-Domínguez, D. García-Bedoya, T. J. DeWitt. Gambusia quadruncus(Cyprinodontiformes: Poeciliidae): a new species of mosquitofish from east-central México. Journal of Fish Biology, 2012; DOI: 10.1111/j.1095-8649.2012.03397.x

Cite This Page:

North Carolina State University. "New fish species offers literal take on 'hooking up'." ScienceDaily. ScienceDaily, 27 September 2012. <www.sciencedaily.com/releases/2012/09/120927152516.htm>.
North Carolina State University. (2012, September 27). New fish species offers literal take on 'hooking up'. ScienceDaily. Retrieved November 22, 2014 from www.sciencedaily.com/releases/2012/09/120927152516.htm
North Carolina State University. "New fish species offers literal take on 'hooking up'." ScienceDaily. www.sciencedaily.com/releases/2012/09/120927152516.htm (accessed November 22, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Saturday, November 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Could Your Genes Be The Reason You're Single?

Could Your Genes Be The Reason You're Single?

Newsy (Nov. 21, 2014) — Researchers in Beijing discovered a gene called 5-HTA1, and carriers are reportedly 20 percent more likely to be single. Video provided by Newsy
Powered by NewsLook.com
Raw: Baby Okapi Born at Houston Zoo

Raw: Baby Okapi Born at Houston Zoo

AP (Nov. 20, 2014) — The Houston Zoo released video of a male baby okapi. Okapis, also known as the "forest giraffe", are native to the Democratic Republic of the Congo in Central Africa. Video is mute from source. (Nov. 20) Video provided by AP
Powered by NewsLook.com
Your Complicated Job Might Keep Your Brain Young

Your Complicated Job Might Keep Your Brain Young

Newsy (Nov. 20, 2014) — Researchers at the University of Edinburgh found the more complex your job is, the sharper your cognitive skills will likely be as you age. Video provided by Newsy
Powered by NewsLook.com
Mysterious Glow Worms Found in the Amazon

Mysterious Glow Worms Found in the Amazon

Buzz60 (Nov. 20, 2014) — Wildlife photographer Jeff Cremer teamed up with entomologist Aaron Pomerantz and others to investigate a predatory glow worm found in the Amazon. Patrick Jones (@Patrick_E_Jones) explains. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins