SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6002f341ec4c267a17bd4df07369b98dd3e0980c5ab744e1eeca823009891d64' 
  AND token = 'g2b9+ITZxByG4NolUtYX8jYkjpMj3yD+hfXFsDWDPBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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