SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b6247f6fec533cce5d356d6c3bb95305764907b1f2ccae3cc09dc2143cfb80e' 
  AND token = 'aKLs0uKAfdcFxVJfQbKAJzBMd6WypayogBUWTQ2/G3k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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