SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd82bc1ae2b858866ecc5cbf09dd0bbb26fcaa22e799ff3948f95c49786c3ce9' 
  AND token = '3ur+0qslWSdxWsjT+gqYhnOaEKgzXbCqx8pypxPVHuY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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