SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f3b724bf4a23748c9c82eba4e8f7875732625c2cdc84c0ad4fb24716fc14556' 
  AND token = 'qIJUCKLc1DSBRVmJPQrOkD2hh5IUnvc1HXoO7Y55df0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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