SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '87596cf06d1c79ff241d4281379d29313b577dec54161e6e66d77e0ef13f13f1' 
  AND token = 'iJLNhL5OhQzUipBYcu+pa0mStKAZ7M3GTvcmMqYJrwU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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