SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b25e924f5bb139fdf503986778f37aa9c40985005a46fd920ddd88818577a372' 
  AND token = 'XybvGKIpA+XIbJlnCqKB79TYlX42DYMWc/1nhrPtq20=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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