SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89757c46f14c3786c9da488675fd4220a0e317a8ddffd9f597239d88e9bd334b' 
  AND token = 'wFvnpXwN+L433JBTTINYjIzcnlKeu5yiglUkVcLuAqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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