SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c9f5579c92d114e579de2c133a37ce5ce2ceb7bec7b0218842216332187d878' 
  AND token = 'LfIVMQ0RorV8BIP+6IqS3M1BnSYlRUJvWG5EP7Ohqmg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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