SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ce181a501189d93d68b233eb8d0bb1879c78fe5bcbb2f7e05639cc2b6ab8a9a' 
  AND token = 'nHQWcxenyov/BpK+DY8IgK4rtCRACLWuTJKlGfO3VCU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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