SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63523b6ab73edca5c19b324f0eb5a20d72da7271299951f11d42b9ec83df0248' 
  AND token = '0OLgdTIPwU4mFwlGf6I5cehdytQHeeRk0yDKozOjxIM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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