SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '78ee80119e1f95b1dd672f6e775ba3f5917355d8385ecc906de15659bcc6cb17' 
  AND token = 'uuj7VJcnD6uwykTB9moELZ54Czqieg/pbk8fVRWe+H8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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