SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '267186774448bc937d52b1e1e78ff1ff4d95e8a7fedc6201794a9f8561ce099f' 
  AND token = 'NxB1BDqkbh/u1KHxPN7PjilBhmX56eXYBd748rLLpvU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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