SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ff560461fe7c3b191a6117cab15791db467e634f3b8d28c4f9820599d20b9e8' 
  AND token = 'AVFapRipgOk7NqOXCz5r5CHG+SBLKdDTRTH6aovQtPg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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