Is there a citation style with just the first author's last name, and year Is there citation style that only cites it as (FirstAuthorLastName,year)
that can be downloaded as a .csl file and incorporated into mendeley/readcube.

However a simple nature style [1] is too short.
And I would like to see the author's name in the text.
Is there citation style that only cites it as (FirstAuthorLastName,year)

Meaning no other coauthors name, (since that not how I remeber the article anyway) and no et al.
(because i already know it's "et al", it's just redudant text). 

is there a citation style that is like this?.

Or is there a website when one can see different citation syles?

Thanks
In a comment you mentioned that you're looking for a .csl citation style file, e.g. for use with Mendeley. It turns out that Mendeley has a generator for, and repository of such files. In particular, one can opt to search by example. Using that tool for citations of the form "(Campbell, 2007)" reveals some examples, the most relevant of which is a modified Chicago style that appears to be associated with Colorado State University - School of Biomedical Engineering:


  Example Output
  
  Inline citations
  
  (Campbell, 2007)
  
  (Ahlquist, 2009; Borges, 1999; Campbell, 2007; Mares, 2001)
  
  Bibliography
  
  Ahlquist, J. S., &amp; Breunig, C. (2009). Country clustering in comparative political economy (MPIfG Discussion Paper No. 09–5) (p. 32). Cologne: Max-Planck Institute for the Study of Societies. Retrieved from www.mpifg.de/pu/mpifg_dp/dp09-5.pdf
  
  Borges, J. L. (1999). Selected non-fictions. (E. Weinberger, Ed., E. Allen, S. J. Levine, &amp; E. Weinberger, Trans.). New York: Viking.
  
  Campbell, J. L., &amp; Pedersen, O. K. (2007). “The varieties of capitalism and hybrid success.” Comparative Political Studies, 40(3), 307–332. https://doi.org/10.1177/0010414006286542
  “CSL search by example.” (n.d.). Retrieved December 15, 2012, from http://editor.citationstyles.org/searchByExample/
  
  Mares, I. (2001). “Firms and the welfare state: When, why, and how does social policy matter to employers?” In P. A. Hall &amp; D. Soskice (Eds.), Varieties of capitalism. The institutional foundations of comparative advantage (pp. 184–213). New York: Oxford University Press.


I have not tried it myself, but I hope it does the trick.