SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e10edcd62b557151c47643d91a3b997067cb13095a64ecdc6c3a6e3a5ba7f1e3' 
  AND token = 'dkp3TpUy1Ksan9+2sq1E9xljBdZ0TPSl2EJlgS1VMlg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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