SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bcc6c17b39ae9cb3808bbf4b1c1cea7a10e42951efce344ebbf5b9cad4c2c730' 
  AND token = '/hOAG4d0K5Je7vm1NMjsM79SNialryjo5tG6SSnjPnI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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