SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed3c9c8185b26265dd734614d5f5d247304d44e747ddf46055c57ef5afe47ba5' 
  AND token = 'BCWWG42zHntpCLWRE7vpAyBI+sQBMJ4bbaSDWP45jGo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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