SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed0202d399411788bbe77c0449272c36616af6b9acf755f181b856ed9fc4f5ca' 
  AND token = '9sRf+jjsGmj3Y3VXoFi4HJqeDl3g2srho6VScHGgPKQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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