SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'df082a864f7183a818713151fac736696e94c486fdab15d9630996d6d2779607' 
  AND token = 'eqGEbf49Sqt8GwcY3VcMJizw36hQbKJiwRSSw2yUeJQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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