SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d98ec09b49015db0d439c8b12b1ed56f100d425d4f7b829f365cc8a46394211' 
  AND token = 'XHLoJ6L5v8TgGK9cfxFX2F10XkyClQimhED33fCqy2Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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