SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62aa5d38f10cc58fc07061acd44d3f7c12350c5fd6843ad76f0e810e76a2f438' 
  AND token = 'RI/0EEaycKgJ6i+xZJnoZpSDvj0KbAuuMY8x9uR+7BU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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