SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7b1c0725625356f34d170b8d5c10228aecd6892760aab46c310a8c35fef051f0' 
  AND token = '4qVvkTiui6vDNGoyCn5TJKUMqUY4o0/Yrr3LKInXSF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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