SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '148d087746ffb6c144e6e92ca00233010f7a458bb55f00be813f44456d829e79' 
  AND token = 'xn4hno7/0GHSFNnsRrPYip2NHuSa1WeJWPCtkNK7860=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}