SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c90c8d7dd5ef481a412dc70259882379de77ea8b92a53ec6e410d82b43c25d4c' 
  AND token = 'RqIJxKOOZoofdqKPKEAX8EGmOHSCBIW1aDXpWueQ7A4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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