SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddd30c525e5fd85f17941966378b48c7f64775604acce77bdc56b3a58fb98adb' 
  AND token = '0Venqbj4sfpfT5EKazlz8/XlQNlEzjL1pvuSvifZq+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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