SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fb6c2eaab6a4bd55cf808b9c13be3e1f6ab2b6ef4d61088a706eb81c485dd13' 
  AND token = 'Zh9k//EWyPyoNwZauyLt3ZLsa9iGGJL54Yq03J3/ZD0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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