SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd481863ece1097e05f03bda6efbd968e7b86e7ad8da405b882f11d476bfa60a7' 
  AND token = 'ocgQMoQxa6RAUptJiVwmfd4f8Hzvax9+wJN4jp2ETyc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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