Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6ef61e8a1ea3693733e0421c68e8fc56c84220ddcdd60261ef1b6c08ba09ff9' 
  AND token = 'Uj9OnaBzG5ZN3pNDf3bHpFYWagqELzhex+f4Zf3t5lI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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