SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac72ed2e1e381225c1e7bc046befb296803f476e73955a5a5b614b4636ee40af' 
  AND token = 'DIZWNqzhkrhIjTYbje50wgP5xXFJo/AGBm1YgRu2Yy8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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