SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1e6c3acafc80e0d8a9fcc6a11e18b7245e64ebd651c16dc1d2b2b58524a86855' 
  AND token = 'ZeFBwx98uunT3wTPnDOawxHenniKx/g3hhLl0jDmCm4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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