SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80d1a35f3c7ad489e3ba46ec953f477cd09898a3af575078011bc809bdbb63d1' 
  AND token = 'wJ2xERH4eFS37U0TUTMAUy9UFLBVYR+6yu5HoX9GZQs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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