This link will take you to a good picture of a Shortnose spurdog.

How long do they live? At least up to 75 years old [1] that we know of.

Where are they found? Around the Eastern Indian and Eastern Atlantic oceans [2]. See figure 1.

squalus_megalops_distmap
Figure 1. Range of the Shortnose spurdogs.

What do they eat? Smaller fish, shrimp, and crustaceans [2].

What do they look like? See the link at the top of the page for a better picture. Shortnose spurdogs are small and only reach a maximum length of about 2.9 feet [2]. They have a gray upper body and white underbelly. See figure 2.

1024px-squalus_megalops
Figure 1. You are also welcome to donate pictures if you have some that are legal for reuse.

How do they reproduce? This species is ovoviviparous and give live birth. They reach sexual maturity between 15 – 22 years of age [3] and not much is known about  the reproductive senescence of Shortnose spurdogs. This is a very slow growing species [4].

How do scientists know how old they are? Age estimations were based on growth models [4].

So what are we lacking? I’m beginning to like bullet points.

  • A non-invasive method of age determination and validation studies.
  • Reproductive senescence data and population numbers.
  • This species is in trouble since it’s over fished and slow growing. Species that mature slowly cannot recoup population declines fast enough to maintain a healthy population.
  • Nuclear genome information is also needed for Squalus megalops on the NCBI website.

Conservation status: Sadly this is unknown. “Data deficient” as listed by the IUCN.

Please contact me if you would like to contribute to this website.

 

  1. García, Verónica B., Luis O. Lucifora, and Ransom A. Myers. “The importance of habitat and life history to extinction risk in sharks, skates, rays and chimaeras.” Proceedings of the Royal Society of London B: Biological Sciences 275.1630 (2008): 83-89.
  2. Fishbase.org. Shortnose spurdog. http://www.fishbase.org/summary/711 Accessed 10/31/2016
  3. Cavanagh, R.D. & Lisney, T.J. (SSG Australia & Oceania Regional Workshop, March 2003). 2003. Squalus megalops. The IUCN Red List of Threatened Species 2003: e.T41859A10581044. http://dx.doi.org/10.2305/IUCN.UK.2003.RLTS.T41859A10581044.en. Accessed 10/31/2016.
  4. Braccini, J. Matías, et al. “Comparison of deterministic growth models fitted to length-at-age data of the piked spurdog (Squalus megalops) in south-eastern Australia.” Marine and Freshwater Research 58.1 (2007): 24-33.