SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0f4712560885133cdcea3208b9617d43a870ffb948f59e770ba1f7229524c5a' 
  AND token = 'VFu8vP4GzaLazP+sY9NQ8MAf8ETGky+uPdCc5VScKlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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