SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22440478a8b57805c049ee91dc42010764df7d9682e69fe288e2fa1ac70249fb' 
  AND token = 'qnHCer6xJEM8ThYvsp5LGisU1agS2q+c5IQQHxUHAjo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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