SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90e40dd71e5ceeba4cfb6ea2863e41bd78235b49c3151499f539d17dd7c958c2' 
  AND token = 'GgjzbFETwypsiaJPlr1TplSaMQCBt/640xOnVHoTE6A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00057

JSON explain

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