SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fa9b3f6d28184c86b19437b35830b75d8d65526c1ac6502b89159c21f36da45f' 
  AND token = 'aOeVn4cdUarcyUbfe0nlnCVdCjdjT8G+2G2AA6H3Yeo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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