Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'c51a92d1097e72145aca26e597b6989453d19f969815a1981c26a7c7cbd02eb9' 
  AND token = 'hgX2Lyuv1vZC+dZ1rIxOGvtcyDJHVceEj49o5PI0nu8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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