SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '96e5df7ed60dd3cb1eeb74b2f5acf8228876ea8df7d5b2350d251529788bb28b' 
  AND token = 'rYWKEpOWpx3Dx7tZhXWNHmaMAl6wLYKHyRMwNyGY0Z0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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