SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '473d3db25aa4e5e4db1612bd5cd3a95515937573efd90236523e4e170b47a128' 
  AND token = 'ZeqzeHH72mpBW2JlvL23IxCzj1FRORzgal5Gx5kmINg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}