SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9c057310ce02e162e6cddbd6cc8d08b61646692ef8271774f9d795588784ee42' 
  AND token = 'OndRbjjhGgFwbnyOFhqqHgNdK3wTCcWQfM91SI/oz4Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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