SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e82f60fa3da4790acc2d6379e6607e1b69b5079ba6e4969fd4f4bff477cdd0b' 
  AND token = 'pYb4CpRaVbWOIgsbZ4TXnwivngnv0vEbYCziru7a8Mk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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