SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '83a6cee611c1b529cc4b7ac4eed1ee3dfc03602a705f5150a5119379d5fcc655' 
  AND token = 'BAc7+9RQYmFLQ+lT5RQ5hZy7Rw89Zq11cNV0rUdIksU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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