SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '423955aec1d2c74392fc69cabe0709824e7f0c90e919d9c84cc8b28925d172ae' 
  AND token = '8oMvFa40lu4bgmobgjR7Eln7xrnEOeCQeGCtqPoONE0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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