SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c26b6efabf32005a041aaa0c0658aa282de55fd4be0b63548e9b87860c3ed8c1' 
  AND token = 'L/lEMOaGnsbWmYnpibMQMvQnbxrtXoWolbFZ7ySPkB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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