SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '115f5e00a8e49190004245b282e27664c265cf510e65b4e5083bffdb8051d9e4' 
  AND token = 'bThpH71ZHtRblQIscyZQmCCeEsME+S0KQu3WUEjHRxE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}