SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2a559fb7924ffc106ba3f391cc3124e28515332b91bfbdeef68c54fdc387719' 
  AND token = 'DC76OMfjWErLcea8g0Nc9t2LNP+U5jRMxOaKqOUufdI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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