SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd747cbdfc6e38b45b82cd70358f06abd523f355cc2301ce923a95166407baa41' 
  AND token = 'hcXCLQvdbejoAFFGE9N9cHxPrXcQKQLYaEtS5LkKf7A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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