SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6c7bd4678ae0a7f75c28c2e425d76342072ac41198eb0919ec4204d7a2b46f09' 
  AND token = 'zOlKxj5wo8YG6Y2B8/1hE7M9UndqHEZkk/Ku6MAiRdY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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