SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '670472a18a8f7ef1968af1152f5650f8732baa35426ef3e7965741a1bd42db6d' 
  AND token = 'yXnb5YMHdEQKhnozIyNhjTgEcornGnwAZrkIvNKkCv8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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