SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b9eda505d6d701d724980de770fd660e442a48c0fee00ff1d0bba418d0a9ee90' 
  AND token = 'XiQhYsOdygDF8bkg/GxNmW/4rocHV4upaRoi0TgRIpI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}