SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'caf42654c72e34ce3f7ac9dd96098db88fba98023d110cef986f824e7f76b619' 
  AND token = '3cVq+taoZou8G/u8XyOg9mUMtp5gXTJH0ov7jQ21+ss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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