SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '520bdec15c1e87fe31174826ab4d17513348bd0c79f050a61f39766c655fb478' 
  AND token = '4Ryw5Bnws63MVoB3qiIoWQHKFGjhVpnvY4YRLt/Zra0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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