SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dddc1e618b278c8036b18c7ada359e234b59a4bd48f777d5c614fa2e46c93f3a' 
  AND token = 'FK2FZzNWCznV7FBL8kXqUm/oCMX82VrNsyqPRgzhj2s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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