SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2fb9db7b909fb08bc44e96b6579241dc76502ac616898bd8d8a12b44529e970d' 
  AND token = 'Jfc8pmoJu0TYZvFydQ1fdBiDP9qG3sKVQsaUS3VjUUM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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