SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b076b16a892e787fb731a6f43082eaa5b1c686a152801e1d152c9cc7bf4028c1' 
  AND token = 'irjcTBESEGftrkxl/x8RZL7ArGQ4kJoZ/OBjiwofOaQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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