SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a53d6504f68339241f7fd5cfd18b63e89e76761e08691276e70cbbd2028e3be' 
  AND token = 'KgzzgU+Z8bCxIfKPQ01udGyqtvCM6HQSGvztMc8vDkU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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