SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'da2b3fc6e2e3e65d2c3faac00cfe28be11329f9f3171817782bb380470f0c03d' 
  AND token = 'v8ZdVc+SdwOHilR9pdfniH9CIdaILs2vmP/B5MIvxH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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