SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c4f0e1fe115e30ec01d9fafa9200f13c66e582ac272a7e66c573740c518e8222' 
  AND token = 'vnHMt/mJ4bO2DcPBQuj3RnDIxdTHmHASUBRUy16uZtI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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