SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9dd7d16192dc48eb3a21af9a4d46f313fef195fc0594161adbfcabf0c7691123' 
  AND token = 'YJOzcFUQPaKGecbGQRNKzmF3YTedHDaVBwFvEVy3ZTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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