SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0630752ae5c9f020e806206239095c3f61c91ddfa981226a0dc22e258fe69210' 
  AND token = 'tJVwOzxFcW/pylDTw61GBeIQgtqYSfyNdVRSBDkijCA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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