SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'beff7cb4ba78ce8f64693cc7cd71068319002cfd4c5a2a4fbde6a02efa361581' 
  AND token = 'fzjudWutNuIK5JbepFw69eqSwQsbZhyczbF21Jjk9B8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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