SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd83dbe1bee599aab0d7af6c6f5727e898af02fd0fa5ff9b71843c6a1b86c8f12' 
  AND token = 'v0LyLy25wDN9IWdxlJ7doVMEGWDId4lt4IPy+L2I0rk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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