SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0abaaae4e419a6f289bddbb46d24e9e8bce3ce408eed4073c668a9a1b189d035' 
  AND token = 'jTaOmlXfC0gvkZqp1mfLada7FKnjKkuYVSi0Lq8UqeU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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