SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '117c2a295e315f1697a8b11aa766617e26a9d144bbd633458d02faff9f0be9a3' 
  AND token = 'JzkdbojYAGJ7Vh51Fzasq+gOme79+rpq/eiLn7jv65A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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