SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '089257259dcaf1d223c09bf61d59af44b6b5dab7bbd14d50e27af2d82fcbb00b' 
  AND token = 'UQALNJFjRkibnurUlLIqzCOYdK+1Zrq2mtkQ7KsCDRA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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