SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9911bbb7c0c285c552ea607737a016e82dcec28d36f89b97dc476ffb8da23a9e' 
  AND token = '5CDvQiKY62xutyqfwbs4eg3OMzFg9k8emjSJnHYMH1Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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