SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f283146853dc33e4734dfe1591d25c81fe11a599a5d8e22b35d5d5c5cec87ba' 
  AND token = 'DwZm/42hRSzICQJLNrXW+6KsQc5V0hHDK9iAoEB0M/0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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