SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd900b1082482a168fa1660c856f7e7c93efecc04285632d32713e71601138ab3' 
  AND token = 'UNI6MK3LWcPN0XJlBZmAJ0GahchmBMmk4uYgC2CyhuU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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