SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32788e83bd0d5b951f1cb164ad429446bc3566fc4de8647e729cc6dbfff0f009' 
  AND token = 'mVjCYf4KtKx1CchWnLMyUWUfTv0nkqU8b24pNuToWOQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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