SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6fb9d1db6bd5e85fb14c69e190ac8954824f9c5935fd8edb432ccc6d698d423d' 
  AND token = 'Hu3HoIprppq/z8rCUy0VPn+A1K9jGhL4u7VXTSeokig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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