SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61fd252f39a73b8e960ef50d5164e1ac5a08425e8101af768bc3a06eb008ef57' 
  AND token = '0LxJwDBYhoYqgYy5m/HggelbnUJCU0PYkjsvErDUi9s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}