SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c72ce5ca17c937536e34e9be55837823baecedacfb9b6fa68858359dfa2afc9' 
  AND token = 'uHGYcd3VxNBmQV9G7+A9GeI9HJ/pNBizOueemQcXMoY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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