SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d31f2f1c40181e55ff645acb4d2d116ee9d57bd8094d6296c564db0e6a05167' 
  AND token = 'i6E4kFwVeprZI9vTXIFj11uXpQkp1slidWVd9V1aL8o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}