SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52766c58bdaf7072db43f2e0df50d34bcdac655f7eb032aa17c008028eea5ce3' 
  AND token = 'IiD9xO9ZdapA0O/m0O8egESgKl4HUvs7GIIlfwO58xE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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