SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da81af9e428f8284b3f1b36caa2b643cedd1ead68b035a929c65a75d315a39ae' 
  AND token = 'cQyMkfJTcTc9T7wRR+vRtsJxlH2FuHm0Rg/b9tY/6pQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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