SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3756f6c003cc5399287d93e43fcc99c3b305c5e7541014159ae9f6029ef3c60b' 
  AND token = 'O7Go75UGFLUNttpqnGJc2CIyoUX1JNtICzQU6eSUYW4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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