SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0e9124bb48cfee75549d22db50aa4f3b9e368c3f4e1a38c176a942d5809f36c' 
  AND token = 'qXefV7qgkiTjlOsfpgGWXuX+dDgVZFMYJIMJsUcAI4k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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