SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f52b0be4786de5fab64319676830c155b98a7b66da907d295dca9f60173fa184' 
  AND token = 'H5Q6tHTsoXMlFUrRUJpIkviRlZlJVNRJEvWznPNu9Go=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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