SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45bcb28ad7671aa31ace45bd772165876fb0a7e51cd85cb8a3a4aaf23896fa5e' 
  AND token = 'kjSBYWNzFA4wRyyH+sBQVfLx8QX/wVi+KEHl3BXKIpE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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