SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f058f26bb4194f286ce57c8d9f8d917bfe00a72cd430cf2aa77b73798af9bd26' 
  AND token = 'GQptUKGWDMmJ1C35jNuHtMJhjFU7TtTMPeT0BrgsjP0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}