SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30d09fe7a3eae676f6e55ab728498b0c81683a4fcb95c8b0fc37c51114947700' 
  AND token = 'Xzh8KT9RBhbsStw25p1V2HYzaghBZIIIgOC2epPV0pg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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