SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3657d1e52c99d6f81189ebf41ca5501dc4afb1be3c528101fdf3307f5169ac5' 
  AND token = 'ATR/unyBoloJyedEKLHG4VsjMQLqlU/4DRegwiXv/KY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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