SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03894597c3e53a46881c745db155001a48ae0411098ab77011609e88f00a8e95' 
  AND token = 'hwez9QXPEtakS5CCOw5i3VNPs4JaDLpUFyighgOkxMA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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