SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a9caf20a8b7b6b8773e9efff26dd64f1135351c24492d3eca35accbfb5ed7f5' 
  AND token = 'ZRMyAiXwEZvsjpBS19oQPcTI2BUuuWjqJs6DS72HT5g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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