SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '888bace019cc7a970fb22dd227ffa49f44a348267cc324cd80564d3a7ecafa42' 
  AND token = 'uiucxIqnGzPdgveQzyVCkIRJXHIVOculxo5n3VAT3qU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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