SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ec7ca8389c585f2cb02e6faf96e02105d3218f902353cbe86dcec62030cee47' 
  AND token = 'd1kPs2CeSAMoR+pEdnWWtJBPLJzrJ5qwU3kRViFfFHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}