SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1803e01a68dfc23becb708f388971b565b38530c3e0392853b2b294ee7613ba' 
  AND token = '1Fvc9AmQViJ2IRSO/aUP6wbCcggirDA6fIYLnBkl9Eg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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