SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d95aeb137e2bd26194efedc16885d6b4c161f6ea2c526493fc07763dc4f2116' 
  AND token = 'yH+ZzAav0B27tGO3AQPNq0xDO0E7xJKUV9EwN+hKnCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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