SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '161f5f735ce9bf41ebc5d03261528d49800965ba673be5b1b5a26044cd31b6e8' 
  AND token = 'aefTMhkbCIUJAmYdINioTtaOW+0h5bTpowqCJFVKkCc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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