SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3e243150bbe340df64dd4657f2238b3b69254c59dec6e4039d4db4ff343bbe75' 
  AND token = 'sZYkzYHLvEAhE9w0lZlWD5sTJArqUj+bwh6ET6XCoaI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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