SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '362380f5fd464d284b5b3ea29bfe4c994d309ebe5a314e626a3bb15bd22598fa' 
  AND token = '9uv9dfaW16AywetkenfJSkg4GdqGRV2CelYqUss9270=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00057

JSON explain

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