SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '928091ef3efbb0ab0342d23c7c9fc841816c94383f6f1573d65fd02d24ea999e' 
  AND token = 'LNjsJR32hlkFMWFrKxdhoCZaeZvPs9zbvBginKbKSSo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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