SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '08fc2a4fbaed77bda285396d162b514aee6872acb32b58795c757e0e5093981f' 
  AND token = '0XBKlbTjuwoyhQVNBahnDzE2N12gZZUnDDSpkNsqrvQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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