SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '143ef98fdab74de6391ff16d564fcbeed1d04f0a9be776582e52d06d7132d688' 
  AND token = 'Ug+BgyIAzzAQGtewQRJVjmjnyuPDcwEZNy9jr2ffoH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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