SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8094d8349e77c69b8054aeffa457dd83fb0c615af827a4cf84751634fe02eec' 
  AND token = 'mYqm5x/17Uv8AP+awuomqJk+b7jq2N9YHoCZMo/7uUM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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