SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa8ce07f2f2d711a5788e438a124ef355834a23116e3b1c0fca3be342b61e199' 
  AND token = 'EvXYdXGhzzJIjF0XLpIc18M2va5jE5RSDgnjHyh29Rw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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