SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '174eed0e0b07f8c46e6dd09771066f149fc68571ff900664d723084eb1d620ab' 
  AND token = '/0DbAmSofBqhDLabsbdO3Aa9jotPvsPcNVdGneHKoDQ=' 
  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"
    }
  }
}