SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1c5e9ffe5793aa7f3c525aa9ae24285b4638f75fbd8f60c60d887eab4633745' 
  AND token = 'ul+90/T0q7zfzsMNjerV4bj8F83ktsrucAO3bxwLTqU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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