SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '04e1e9953cbe3e7f7f46d57a00b2f5129b49b6074a4f5326bcd2ad17a70d15e8' 
  AND token = '45Ht2AB6ahjlbdoK+JJJjGMYpkNHPCQNA6P6qnaxKFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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