SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f4d05d0e3229f370038ce67572f80c6b970a822f063751f72252982787c0f6b' 
  AND token = 'boruJjs0WpzurCklf83/+VxCOBVbzFUIQOhGE/GY+38=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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