SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8391adb994ff52c54ae2805026412ee3145db758e8c9daa31cf6e5728824ca94' 
  AND token = 'iXZuxl/rNNUr9gbQivL/eQg/1Exe0YJ0fgn4lIGJ9pY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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