SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ebf091cd1f98a3c13a0de763cd95647a293aefaef582dbf56edc3ecd3ea3557' 
  AND token = 'TLZlsmmQcg5ZEToj/2w8GCIjmkLYhj14vx9oibthUkE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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