SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '3d976ba3790f200a8f92ad811c44635c4154550ccbcedcc9c67db3aad3503f2c' 
  AND token = 'VeetEb8x70qqrAf1WFUsGsaTFzKPMGU2N8dnmlGWufM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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