SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d98f183f213a1fbc1a5dbb366eb58fcf174795fff8a275ba6044c3072774ad3' 
  AND token = '1qqzK4rukJ88LHYhYEiwxAkn2CO9ANln9Y/QOmqyj7s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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