SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd24af58fe14347978460998c7efdc42302024a829f4979454b690024d887410a' 
  AND token = 'DUiVxzyd79l6fSvr8Zk0cFzQMIjsHd8REhEG8EOtAbw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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