SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e44383bcee1f8442bf349cd8d70c71816dc2a89fbbd775d59a243fcce44749ae' 
  AND token = 'zIQWAvtZQFkHPR6OprMQwWMYsBobBy2RWRrerYWzMDs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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