SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30d71172f6045b3e15f377167a63edacfc228e609f45ba9c570850c7dcb9d8e4' 
  AND token = '5DCKj7GGrzFZpFIm6xdw1E+4dqXuImshRKqpptrD+N0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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