SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f73e9efd750fa2b95dfe15e4899ea00b3cfc20282053a0247f99f4acda2a6501' 
  AND token = 'cG3sEzMCiotVDSodO+L/qs3pZTefSmSvnrHsqDuRJF8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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