SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91e8184cfaf0b5be8101a8981e4ba25776c337358dcd76b5919722abd2394515' 
  AND token = 'eoThkjSZVfhNh4PD0Ls/yzN9ZgFjI9G0bXMvVUwDh7g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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