SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5a6edfa843e3f19e535f2f4b9cb02a049befc9c4456117dd54fc90059fe38ba5' 
  AND token = 'NqEjLwEyEbP90r50fYZ8DwXr/Tvn+Ke8pC0GJFcespQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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