SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'e2e07e7dfeb1f44d26ad476fe971499c483a68e11d69b1caa6f8126c55efbb20' 
  AND token = 'VnaY9v+4oN5eLVajcsyiLdEtUl7jLieVmCrgKIxO0oc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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