SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3f3bf57fde498fcb558a2ab92e647b517262edeb5821ad28e8d6d4102ac1a646' 
  AND token = 'sofJl3Uc8/xnfQUnGjE912L9MFttGUfS2k8L37nxmOI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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