SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0a31da5d5e30a2962b5c203f8785fd7ac65a34456f01a2bcd890ccefbd6f7c59' 
  AND token = 'uu/rw84aTQilzJqtiM/jroKUfKlmIF3xO+XPrXYU15U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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