SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98ce5f444281285268c7ffac1acc4984b5f1e4844c2714418b6c4160acfbef5a' 
  AND token = 'w3EY57wm5CVA0g0h7JwoRvEv17XC13P8ZG5pviI2JEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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