SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ee985f998cc8585880a2be070312bad0a73a381b5df85fd1a07c7962ed11356' 
  AND token = '7ohmT6/+WLEg5uiWhpw1qCRSHMyTHHfBNW3ivfczJJY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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