Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0743657cd85f9f1ba88e8f00b0c500e9e828d8169e65d4d5b747a8e3ce27bfad' 
  AND token = 'iqv4ghS1bjmhT3pZw3h6nukQVyp49cF0Uek/015THpw=' 
  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"
    }
  }
}