SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d9fb5666669aa85cc8e7ed2fc516aa0ba40ec08e2bd7b88d85198f0d8c34bd2' 
  AND token = 'H6D64g/p9PmPLs7qVlKUm2C0pCAd7jxU5GEAAdBChgA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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