SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08dad3660673eea35deeaa82bec40b0224192dc8c86963a6c272c7065c3e636e' 
  AND token = 'rEgEpy3ARAgEfjgahmb2dOHRjUqjrsOtTOn45gPhu6U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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