SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4aae5a942356bff53d829519b2e2c3406f8b51b0bb7b0887677c303c373a6765' 
  AND token = 'vWHpMXwGcNuP7C1xUFS4hOpHI/vuMVpI8PgJKpnWdjY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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