SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ba926cc0723a2c61eab8a15a823cc40e5983f8814e6cdc9189aa14fb62a8bf2' 
  AND token = 'hGxGv0mlehJ8qVwthMrPD2INRKGJbElkWZf+/dgW9nY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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