SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '728da88f6096e2baaa4e390fb953d1380d36f67f5377a6603655e68057332001' 
  AND token = 'GPA+oyYLEvds1vGNrUvPdD8HgSpXYHlCGM6QikJ0UQI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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