SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd2931478db149170d194ea5e441aaac497ce6ed6169eb19b72d6392d4706675' 
  AND token = 'DxK9EBhrXCDR0jmGFy5Vwx6Jj51hgDttEFPJfCMnKiM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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