Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ec83ac28b7c2c52d8aa81974d9dcf52c528ef175b283c1fcfc5b56c1492e2bf' 
  AND token = 'dcTK56ncNp+AG0NVyJEeYs7Oi0pFj46Okq3Xm/OgZ80=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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