SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa300829ff4717ab9dc38c03ccc817ac5eaab95370ba67401f099fc1adaf87c5' 
  AND token = 'gMBjOd4zb4iGCdObopXW8j1nEFfOcfz6qaRI3PoOX60=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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