SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7560b9f9f73d2243973aa72fc71670d9968c7be562487cc4b5412a1b1ce952a1' 
  AND token = '/XSABhfbqaakuiUrwuqinLv3D5Xph9KzVBRWLPhWpNs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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