SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c232e8673142df70eb52f9d280466067c054d32670dd239beaecac1039577552' 
  AND token = 'HFO7IrLs7QWjVGfjaSTJ6w9fPQDVwPjvAibZ3auSXuM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}