SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45efef07318e8bf8c8ae0c95db5a63feefe6a732eae21b621b5e5b5aa030ac10' 
  AND token = 'DjNrZ1+FQINgAodTfEZJSi69f2xye8zSFbBGiuMtCeE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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