SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41dd02584b6576903274f148878dadc8e11753f58834df45c949c75f1babc2ab' 
  AND token = 'N8qPkwb9weVtdWlPHCaj5GqlLR9kuy/DyMWccxafV7w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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