SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '6b5fbe3c839f6f87fa0617bede4149121888fe2cceb6a320427f937eedcedc62' 
  AND token = 'dqnmkwF3TOcrJgdoQZAWkSJd3C4mL2FHBiNMSqhb/iU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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