SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8936b99aa43a22d2e38b86b99aeec8188413537c2682d352b9aae69ee09756e7' 
  AND token = 'tLqlyV352WSOAEtWuA2mZZhe1fZiDGqIoiJMrQ4LVrI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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