SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '136d0a929319f46461b2c16813431bfa8290eb7262c3fc586226aae2819ca275' 
  AND token = 'fRPI+Rq7Gr91ArX4JcBihp3JVN8WGBaAXu3tD0KQ9Cc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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