SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ad50c96974fa4283dc40ea1fcad62b5d4f7370d8c51ae60ae63824ea46e1bb56' 
  AND token = '7HqWmvuKzEWvah/OZBUpqJXaeoxjHiauE6281LHQ0hc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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