SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '235d8f3aa463eee0c97f7788cdeac5c38c0dcf54ba7a5037fb0aeef2ec4c7efb' 
  AND token = 'd5pfkJanKqLw1NEfqaziILz0rBXQHQr+itGetAmTo7o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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