SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2057ecb73338574a8be0efb32e97e535745f01fdbf04a41515d86e09cc6fdbfc' 
  AND token = '2eSQRr5NdBjTsFDg2mBnnAOtG+oEmN7zDkH1Y+CpFDw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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