SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9972588d7adf326a45c76a907c673dc4086537629c1226a522221ef6f2ee363d' 
  AND token = 'pNMzI6VdCAvXlFFjg5wysegQtKTJXOyFJc8Dn2+cWPQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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