SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2f2ca7cc7a402f8d39a669896b685d6e63f0b38145553484345c36d6c2e3c3c0' 
  AND token = '0sZNZfwUXJ39TLhmfqbZC+QKuHtUiq2D+10DC3g/fk4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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