SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf4faf193132ed98dc298a442fd7e9b9ae0258e8aa54c318e563642c810a1bff' 
  AND token = 'ZOq5AbWXRron+hcSkfusCKThalxvDkh8gwYwU//dl8Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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