SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5995c87ae9bc4a1e148a687b1c46c73fbcad7b381283f09c7c0af05ec782f76d' 
  AND token = 'IMD17ffKczDLYWFdBI0vGgKwRFK8UwIjnoOYsAXLW90=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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