SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '299a80a3477e11d8f03223f43ee7e193516b1eb1338e305aaa81f8ce00854739' 
  AND token = 'Z5IHkOlttpmkN2jyS4S2EdNvCVoGmDIHdHiVVYdrthE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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