Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '42f12fff5be1d65550f91785b557fbdd7ab3d7aaa2f2d3eb65afe9c60f6d78b3' 
  AND token = 'lSn8fdQn+z3lP8lEKXt9IUjYCxq1VglNnCfILc+rKkM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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