Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6d2aa0956179727cae74a220fae5312ff501496804a9f2d7e5a2ec6ff6d1685' 
  AND token = '4xY5km7vklatkDBAIU87FVdRgYDk0/0OJ3pgAE5Zu2Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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