Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a6292c08186871c1b0a1360a032ef8735e1b0e9654dc804eb850f72dae8ccb14' 
  AND token = 'pdWQydn110DxBpfvACzjZnhszYxpul2+xqfzwjCt8vw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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