SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '067e0fd5f88a5c1b6d5b7641ccf8188aca3544adae2a989775922cbd0be12d1f' 
  AND token = 'tJ4J5ZuNoLWV3rxstLnV7fx3cL4cBCQlcCLT+S+DrBc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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