SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ffb2b5965bf82e9f402f189b432a63a1907fc286496cf2d8c781726a0cbefe4d' 
  AND token = 'nMGT9Wu7vxGsBI0hZHM+VaXiZTgL56PxyN0L9BDK3bI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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