SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3876c4d6bcc2d981d063518afbce06fa033010e3c7eda899bf4f895a40f49320' 
  AND token = 'vuDmZKjOZ+7W1B4vTL8bNhxQPe2/0WdtHJYhqftrZf4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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