SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdfb972e622bad27dc330d88fe6443b5ca7fdbf4e24c74155447e931788725bd' 
  AND token = 'VGnRpf4WicFNTOcefdocIFrJkNc0BXq0BRrokcM/H3M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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