Since they don't have claws they shouldn't be a problem for the Betta, however, anything can happen... it might be more of a problems for them not the Betta.. google Macrobrachium lamarrei lamarrei and see if you can find more info on them that way
Hi OFL, sorry to bother you but I was wondering if you had any information on Indian Whisker Shrimp? I recently got one but I'm worried he'll hurt my betta, I tried researching this species online and haven't got much information from Google except that in a group they can attack fish. I'm worried =( I hope either way you can let me know that way I can take him out and house him separately from my fish. Thanks OFL, hope you're having a great day!