SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2efe689ec6ccd6292a542f8393f68e7a827b10f093ab5588ec4518fdaf1a815f' 
  AND token = '7jpxn9Mtakr/dxG3KJ473iSqqjXpEVWQYLiSoidr0rw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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