SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '89dd63d809319aeff74189332c9c58b6254c29997aef3b4ee2bbb462a13ab976' 
  AND token = 'Ffg5OPw0n4RJL/mH4inO0SQjHgwZuCoN/prurRsWEZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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