SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dfb09e15aded55953cac33ed247afb6eb8f92efabc9b7c2f2e710bfd9442697a' 
  AND token = 'QCZ8dHJ4MASwbQPUT2Ka4MYwArAcxBoH64O2ub8rot8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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