SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '442d3c72acbd2768160f2cbb799f5a3f1be6713eecf7c4ca7de980504873d6ab' 
  AND token = 'V6DBZIuLYpgDl2KNuWXQCT/wTc8Sh925ycBNwwu+iIQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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