SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3be5fd59c9e243079bac12cfdba88814fd562b56e007c3952bb80845476e5db1' 
  AND token = 'oggzFBnqnKpcUm6gBEJH5CnB9QsgC7fivHpY4y++a+g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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