SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '852f7b76d7448cae2bfb9bd92f1b2e4a54cc50f300360539e67aa694eef6f7a0' 
  AND token = 'B715lU+E/rLfGSwWtDDcgOQvXSCDkjwIbAYDvzs/ZhA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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