SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9089d0dc8ff58a24d7fde06b42c965cb5d902667b9b96e8faa1feb2b033f403f' 
  AND token = 'WG19+P/nnoJkoAalZ3dehuMRtBBskmVcEFKCCnkDlD4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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