SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4bf6aab5a47cc22ee3ce921f855fa565c0723a1ba83354735cf7f16349083a05' 
  AND token = 'XDUGkmibiGh+5RV35Aq6Iq+zlk1OKTVJYD/7ZgXn5Ic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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