SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9774b6fb09f5cc620f89f4774579aed3365300e819a0ad96507191217bf18ed' 
  AND token = '/VGOv2de/6d+3REla2SyZAqYzauP/a3nJCCTJCdP+ZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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