SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f6d88158b6f85ce6beef70533621ce25a17b197a0c6d7284047340990321d47f' 
  AND token = 'Jw6DXYx2WvX46Y+4F8J4/XEhGwPtOq4RiBVN5oLYfcI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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