SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '153d44fe9d2286d1deb6e81c999fdcc7877cb1cd01f65e8ffe7a9abe3e5963bd' 
  AND token = 'BSlG9yUbtNCvKSVFD+VLvIKeYmFSjHvhkJWNny2xghA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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