SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9b47dbbccca9bdb88926f6a6e2c65d3c63f7894d2f893a60b4b6ccc417c1bc7' 
  AND token = 'kGfX9AgEfzoARvtMSCIGwxyKpaMsSeUweeQU/vj2FQQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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