SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de6172f374b4a6c137ec75083c8705685f22b02ea3fe38fbebf87ef0b64fcce2' 
  AND token = 'JAW+CcmkEfFCfVshXUx/Lv0XiTV90GqBKrAzZbpLmUQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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