SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '79808b3d9ebe3958b6052345e23e9770af5dd9d7735e9b1b0e3f025aad2c24f4' 
  AND token = 'Pq9LbqZW/EfukyV/hshhrrOwIuIG/lyKMrBYPI9hJ48=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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