SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de225e26e8ee6cb73521b834cdb4cd70628d2a962656f181b296c63996815df0' 
  AND token = 'NZLkCJX0MBzggcUNdQScNoVcueJaXuufK65asPXFsog=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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