SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f497b61a5b8b6f331ac98b2bed64c46eafdc0eaeeb4e6552760ed909d8326dd' 
  AND token = 'h0BkIwENDDd80Uda0oZcDQXFBoicKqZl59WkhCmzx7A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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