SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1b4df9792b38536bc1a217f65ad1bc136c64b5a8c072c72e391d186b51d5b41c' 
  AND token = 'ZQiGtupWmtwM+LLROQy0EgWO3wprJBQFuTJGCjH+4X4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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