SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5e71c252094e24a086de81a9c59781c4b010a5678ad2e9157954cac004a82bb3' 
  AND token = 's9AMsyP+VE95vXQdRwWKqvDXKrpI3g3/mEhcRRA1KXs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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