SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5faa274d59e7b5222911ff6490a65cbd9ecfe18c580fdd56bd522015f284f867' 
  AND token = 'g1ecOp7c2Xqf3JHq4oSDEHIaXhDiyZ6h/c5bAQY1gRI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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