SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c1cc13d719f8d4cdc584ca2ef9ad888301179c623989292492d4832a978da7e' 
  AND token = 'yfjRftKHX0ete8x8RvJsVpnNrNCwZR6OZLl/H8TOIYU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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