SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61d2100b879e4473a248f86c23235a4d9b5e95f28b6828f44a4f361e1fdddbe5' 
  AND token = 'iJd0oiaNsTeMPcOkHQf7oaKaxjtdwJ7QIUSW3dYA8Fo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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