SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'c5b25c54150a972c7923f5a8f40cb75a2634abafa537c205c5419d001ec47c04' 
  AND token = 'YfBJpGP/lDf49juGO7SAqjrv8cRSdnhGdgoKKlv7B/o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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