SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e658ff81f37bd52aba2317a3c51ae92ed683ba5895e8cf12ceb0103de3d344f2' 
  AND token = 'yXjwLPusXKcAffY8cxtAq2H25oQzmhnZ/yaxGD68v6g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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