SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '240da822a0110fffa706ffe8be6f5b5fb3914578a568d363ac4cf518ea6cd522' 
  AND token = 'FG6EdxFrmdPQtCV7DDJuBxJUm/8PX8nMr/ip78XxF80=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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