SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'eb148a07599b6a8781ba9c5f1429097df8e93382cc82fba385f46d06a1f7c32d' 
  AND token = 'juNmyV3O98JZD50tJq6he7JHNNic6vszU+cHi4zfMOk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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