SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca8697bc6806362e481a1dcd3ef21c4ae5c1cbee79623ced152e303eb40581f4' 
  AND token = 'v/NVqUCYswjssgZN+mHr8+tIWUq8Oo1wagCVMQJaG30=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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