SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5836da15f0967eba1c2cfc4befd17afc5b30aa7edab5c60e024ffa1f66080258' 
  AND token = 'bEH9ZrOwDx5x+RVWPf671+xf7BpTqnzJNKb+MlEflyE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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