SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cdb812b9b27aa5e588a468780c3252429ef3d695372b4033744efd634938f459' 
  AND token = 'EY10JKP6ji1rPhZBHS6o24sWC+/yU/pzOUur6nLwqyQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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