SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '695d0fdd1db6349ffb119ee8e9aff5f51b24183820cd49727fcb9fe655bd0382' 
  AND token = 'vmhBFLNGvhTHP5nKSTgYYD2aCwQAeNEYAn+VE+9g+tc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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