SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a9ff978a13cac640f6b6a3c35603a12fd4a65a3856d72ff892954f2e197a2b61' 
  AND token = 'jwzaBTYHVohtmHDZECaReUJajAWu/u357ptISmB6S9I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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