SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2d89184501e5ffe1275f5330bada50599fad1e3080840eb03d1fec95612c68dc' 
  AND token = 'tr2KUJ/7tUvnzj1MHFvbOx0HkQWpq6+emnFDltVNdlE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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