SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8da73da9ee77ee3be2c93ac345fe46bd904a3d1d5eeb12696ed42c42747061c3' 
  AND token = 'RyrWWfRq1Z7i8vfMD2DnjsEDEOdLlVTfHvVh/jJjBek=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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