SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9927744b68c87aff208e6b009e5e0d46d129579a124e6d24f92bc88c08c017c7' 
  AND token = '9AuPoZH1ojJH+monO2KTvJVZngIi92xRYwsIF0glxtk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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