SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13108917576effcbdd6172bd9ac899243e302f4db6197ba81196b81e3a506e64' 
  AND token = 'Nutmp5REhcCEUmsvB6AZXzZXfikK/s+lK68L+LptTJY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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