SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd5aacf30f7fb9b5e37e8805a5923bba58f494310947181596028c569841a7e8' 
  AND token = '/0P79rRCXsguc2NrYm+TIYUrmcj7qvItx8W1y4zDwgk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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