SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c9c7ec5c77de935e0ffe693dd38f128b7d674fe29e6f9b28673f4cdd9b069dc9' 
  AND token = 'aU7S3raofIpbmUQo8FkOkkWEtrawr1Sr6FAsQH/Nsd4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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