SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b1bd7a85668e755434efa5fb55679ca8d6e6e0fafb2cf782ccf05f46f0ef2a8' 
  AND token = 'ielUoPgaaIaTOppVdvNDNWVKtgQf+sYoKw/o9WpIM2o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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