SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c411f357b9b4823c8727b0a49b5b23f15cce23816a2a7363c0c78921f0ecd8fc' 
  AND token = 'mxNfjoLq79xVQQGRXO7cXxj1o1/WuOhZ4izHX5auY1I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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