SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3cf342349dd22fe06354276413863d75242aa46300dcdc5265e931a7740ae757' 
  AND token = 'TEpuWlgqMXTJ/Dj7Dj+GF6ZdvEhKMdH0CBEkNmL9tjE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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