SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d71464ca3c389c4aef38be24d8238e221e718939eb9dbc160e517102fdcae7e' 
  AND token = 'OPM6CyE6ptt52Slsqtf9Tb1EQlzOlR8jPVuqI8uygX4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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