SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4b6f60b7f7293e77e1adf9126f2c6a38441f9c710e8e2ea538cbad4dd6b10fd1' 
  AND token = 'Q7RtTvxJZhEotLdn+cH7PC6NiyBhyevd/nhQ5GZJi2Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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