SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '255d0bad3592cc8b69e8fd02562c9c8e3228aed7b7ff5fb7430f2e100cc632a4' 
  AND token = 'ukZtrFrAU+DOQ39NyhRRp98zqY7DQtFQVEU+8bIqZes=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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