SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b7e8152b623af3fd6aeec8c50c7383aa19a45d4d8c9f5559a395f3af4fb3d9b5' 
  AND token = 'Ol4zFRouwBaWkXLXfV2ZdvAKB8nZK5vcjCeMQrzgRJI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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