SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '04295faa38b65bbb80b4948c2b17cf6c7cf65802d4dc9366cbfc97a933a506a3' 
  AND token = '4GGHNN1BbHqdtteYugRzpHGyKuHvzpnoi6wEH/ZFdug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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