SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80da71c1df330ac8f9997f0d7a34d575612c79fe5f693a4bea5e8226045db04c' 
  AND token = 'qGjZXbRGF7NCL81vnufd69utZiURkJImQdU8wwwuXYc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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