SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c714c5969d6e6eb5135f687e425e1123fc84554ea3aeba34bf9fd45629b246a9' 
  AND token = 'hfHewfXVBWHEL5A6f/dy/xuEo5MOMnDkxk6gX+vUTBE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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