SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2571b1eb54ed02035ba717eaad41e410f33ae82cb6f702765c17bf7ea9736299' 
  AND token = '17ggT/lcVfP5wsFBXUMSNhZvTtmwUCV6f/xxRLjKfx0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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