SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a3b83eba2750fce626481a42d3da98215558120580c4869fc67385fb45d2d996' 
  AND token = 's4sZgWmOFQB6twVheElFvR2oc/ihY04pZ2qxzNnJaAo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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