SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b828384b25e54c5b1107e0f4b618cfe7b80ec7ec624b97df5d06147155e99b5' 
  AND token = 'bxwnFIXdNlkxCWVoqsW/JSc+02Gx2EJIu3v5/mBZtqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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