SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd70c7b403d562edda33c53e589bf2aa134e77ad250c4cdaaaa6ec4b91cf1c64' 
  AND token = 'vTfNcPwmVnOJj1YNKBcZWEX7GgoZwUgUi5O1zHkl3cw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

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