SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'edee4437f779888fee998f1044908f3fb472c883d4bc99e37f776aad5952ddde' 
  AND token = 'VbaHzF4ce2A27aaTu3UMXXgY7j0p7u/54fUnTPFxBpI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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