SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2acc3a52c6dbe3c8024deec49c4e915dac8c7ff0c51bd35bcb9f8a0ccd33018' 
  AND token = 'crVUSdYOQr/rGnc8nvyuCArXT1/RdyzPuZyUdC3g8CI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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