SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fee2760eb1411b160bf9698e376dc8ffd2ecb2e99c934e2ae4e69a028a9f169' 
  AND token = 'Ng9snK44LR72DM6BgEHELu/jeTZLS/H+pcWOzL+e1yc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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