SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bcb001ba6a0c00bb6afc998ca54024bb9104d7d56253acbe2ededd72edb93534' 
  AND token = 'fVLHbQxmA++80ndVZjLad5PyY8VZhNbq2yxiXpEgioM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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