SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9636e953e88d334d357e685a185169641fe163ca15786efbd7b31c0c77ca2b48' 
  AND token = 'hZQ9wUd+1xpDYZeWU2FQVo3cAmHoNi1YsLxTHHdNj2c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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