SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '905822bc7e7b0c3eac55ae0cf380fbdb4dafcfe448dd798a9de2db53a14d36b1' 
  AND token = '/c7tv4vHRxiO+yrQjQem7VmguPVf36IrlDwR2gh/O/U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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