SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f1643ffc27e210ecf8b389248dd9094e61099c1f95b02253a93ff4a6e633966' 
  AND token = 'VjBQbF+xqo+nXaTooVJRkg+iXxZiZp5yRSy5juTJJ9I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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