SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b2b162ea34f491829c54a5dd57ed2a1858b5410d35c1109da71a616337930c6' 
  AND token = 'UMBgi/qrTiKmJCKwLuC/696tghl6q+i7N0KSJkMMMsU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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