SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27a0158ee04dfa715489a63e32ff70adc3aa644e84d47fba37618a65a208db69' 
  AND token = 'U8rH6mPQXpAu4yHoRHiFSdEb+yTYJqkwq5fAI4nDt6I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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