SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab5f06c40a12f2bf127ae9b2d7db8251fa5111086b427210c729e235b9c7a6d4' 
  AND token = 'UwTEzVXqGM0A34f8CNfnfndmZcC8T4gKGGMxRjnIBZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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