SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ee31c77bc66ec1fba6aaf79b4a9e1aa1703f8add31d67690ff773fb065b3883' 
  AND token = 'Anw7cgdNVi1xuwDdORoI3AMApcigVD34IGCZeIQUqno=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}