SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '67e865fd68d94777b9fa7cdb791af5f380e46a8a8574990aba0d7e9dfe56666d' 
  AND token = 'v9oGjz416dbvN2clAoXNOmDqUvVu9FptYwVK/lFom3o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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