SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7d13fb5a42cc7da9daafa7a95298b553009cfc15b0a3c1d9e486ad037c5bf10b' 
  AND token = 'ngkKcBlyUIiEoOSFIajZEjVZLlHN+SsowevzojH87Rs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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