SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44468228481e071dc486652c6737044932beb248911f69156c3ce28911faee1e' 
  AND token = 'Nto/qLxUeGIVGKhAxEIhHfsYkelV8tQ8tDBnRfXEJZM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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