SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1487c47602aaae7389cd708353c4885c8ad1c608158ceed4dc217e3001c92971' 
  AND token = 'NDk3le4zgb825mEQ5jehx7b1nY0zXpgBigwLBhHUQs8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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