SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '7fa2720bfc2b989db1435053a10506ee34c4abb89eeb08163108d723c200bd31' 
  AND token = 'Vq/dEkkP4yTqTyv+BhS46MASd8MMDVEd6IdgpHA98l8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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