SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82824424b9812190cb1f6505c30b4f611c72448da190f53129c51277cc0675c0' 
  AND token = 'mtURnIEJguFUa+TRhtEkVaZbUfa/ZbgaAiU/2ajmwCM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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