SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '4911fb37e903e096ad1ac4a9dd7c82c2b728ad9776ec130eb8e657c81f801da3' 
  AND token = 'PttQUh2/GrKHMgoD+zqUgpcmNXRBME8Sq/LX46zdwJI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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