SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4afb474c2a675c1cc181be6490d6f9da8f50ebe1149227b915dd6397d59ec44' 
  AND token = 'IN8e4Sk2qqy3QkLJxzETGBZnU8XX/MzXGtE6+C88zsE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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