SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8ec5d54c0dca36108ad99ef163bcfed374b7d9cbaa83005cfa35dc0aa7efeb80' 
  AND token = 'JFG30JBu+OCws56PN9sZnbSfkLEZtSq3P4S2QJHknXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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