SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd655f26a22c0dd5963c74fd94d5cb454637792cf45ff7d8802201677966a5f95' 
  AND token = '0WEjg7tuJ6qVn+rkePuNNwPjYGkXtUA/KkiVh59+p3I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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